BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the formation of a novel,
stable C-10 carba trioxane dimer that may easily be transformed into
different trioxane dimers. Some of these dimers are 10 times more
antimalarially potent in vitro than artemisinin. These anticancer
dimers selectively inhibit growth in vitro of several human cancer cell
lines without being cytotoxic. The present invention relates also to
water-soluble carboxylic acid derivatives that are thermally stable,
that are more orally
efficacious antimalarials than either artelinic acid or clinically used
sodium artesunate, and that have potent and selective anticancer
activities. The present invention further relates to antimalarial
trioxane dimers that are safer and more
efficacious than sodium artesunate.
2. Description of the State of Art
Each year approximately 200-300 million people experience a
malarial illness and over 1 million individuals die. In patients with
severe and complicated disease, the mortality rate is between 20 and
50%.
Plasmodium is the genus of protozoan parasites which is
responsible for all cases of human malaria and Plasmodium falciparum is
the species of parasite that is responsible for the vast majority of
fatal malaria infections. Malaria has
traditionally been treated with quinolines such as chloroquine,
quinine, mefloquine, and primaquine and with antifolates such as
sulfadoxine-pyrimethamine. Unfortunately, most P. falciparum strains
have now become resistant to chloroquine, and some,
such as those in Southeast Asia, have also developed resistance to
mefloquine and halofantrine; multidrug resistance is developing in
Africa also.
The endoperoxides are a promising class of antimalarial drugs
which may meet the dual challenges posed by drug-resistant parasites
and the rapid progression of malarial illness. The first generation
endoperoxides include natural artemisinin and
several synthetic derivatives, discussed in further detail below.
Artemisia annua L., also known as qinghao or sweet wormwood,
is a pervasive weed that has been used for many centuries in Chinese
traditional medicine as a treatment for fever and malaria. Its earliest
mention, for use in hemorrhoids, occurs in
the Recipes for 52 Kinds of Diseases found in the Mawangdui Han dynasty
tomb dating from 168 B.C. Nearly five hundred years later Ge Hong wrote
the Zhou Hou Bei Ji Fang (Handbook of Prescriptions for Emergency
Treatments) in which he advised that a
water extract of qinghao was effective at reducing fevers. In 1596, Li
Shizhen, the famous herbalist, wrote that chills and fever of malaria
can be combated by qinghao preparations. Finally, in 1972, Chinese
chemists isolated from the leafy portions of
the plant the substance responsible for its reputed medicinal action.
This crystalline compound, called qinghaosu, also referred to as QHS or
artemisinin, is a sesquiterpene lactone with an internal peroxide
linkage.
Artemisinin is a member of the amorphane subgroup of cadinenes
and has the following structure (I); "Art" will be used for shorthand
in many of the figures.

##STR00001## Artemisinin or QHS was the subject of a 1979
study conducted by the Qinghaosu Antimalarial Coordinating Research
Group involving the treatment of 2099 cases of malaria (P. vivax and P.
falciparum in a ratio of about 3:1 ) with
different dosage forms of QHS, leading to the clinical cure of all
patients. See, Qinghaosu Antimalarial Coordinating Research Group,
Chin. Med. J., 92:811 (1979). Since that time artemisinin has been used
successfully in many thousand malaria
patients throughout the world including those infected with both
chloroquine-sensitive and chloroquine-resistant strains of P.
falciparum. Assay of artemisinin against P. falciparum in vitro
revealed that its potency is comparable to that of chloroquine
in two Hanian strains (Z. Ye, et al., J. Trad. Chin. Med., 3:95 (1983))
and of mefloquine in the Camp (chloroquine-susceptible) and Smith
(chloroquine-resistant) strains, D. L. Klayman, et al., J. Nat. Prod.,
47:715 (1984).
Although artemisinin is effective at suppressing the
parasitemias of P. vivax and P. falciparum, the problems encountered
with recrudescence, and the compound's insolubility in water, led
scientists to modify artemisinin chemically, a difficult
task because of the chemical reactivity of the peroxide linkage which
is believed to be an essential moiety for antimalarial activity.
Reduction of artemisinin in the presence of sodium borohydride
results in the production of dihydroartemisinin (II-1) or DHQHS,
(illustrated in structure II below), in which the lactone group is
converted to a lactol (hemiacetal) function, with
properties similar to artemisinin. Artemisinin in methanol is reduced
with sodium borohydride to an equilibrium mixture of .alpha.- and
.beta.-isomers of dihydroartemisinin. Using dihydroartemisinin as a
starting compound a large number of other
derivatives, such as,
##STR00002## artemether (compound II-2), arteether (II-3),
sodium artesunate (II-4), artelinic acid (II-5), sodium artelinate
(II-6), dihydroartemisinin condensation by-product (II-7) and the
olefinic compound, structure III,
##STR00003## have been produced.
Artemether (II-2) is produced by reacting
.beta.-dihydroartemisinin with boron trifluoride (BF.sub.3) etherate or
HCl in methanol:benzene (1:2) at room temperature. A mixture of
.beta.-and .alpha.-artemether (70:30) is obtained, from which the
former is isolated by column chromatography and recrystallized from
hexane or methanol, R. Haynes, Transactions of the Royal Society of
Tropical Medicine and Hygiene, 88(l): S1/23-S1/26 (1994). For arteether
(II-3), (Brossi, et al., 1988), the
.alpha.-isomer is equilibrated (epimerized) to the .beta.-isomer in
ethanol:benzene mixture containing BF.sub.3 etherate. Treatment of
dihydroartemisinin with an unspecified dehydrating agent yields both
the olefinic compound, (III), and the
dihydroartemisinin condensation by-product (II-7), formed on addition
of dihydroartemisinin to (III), M. Cao, et al., Chem. Abstr.,
100:34720k (1984). Until recently, the secondary hydroxy group in
dihydroartemisinin (II-1) provided the only site in an
active artemisinin-related compound that had been used for
derivatization. See B. Venugopalan, "Synthesis of a Novel Ring
Contracted Artemisinin Derivative," Bioorganic & Medicinal
Chemistry Letters, 4(5):751 -752 (1994).
The potency of various artemisinin-derivatives in comparison
to artemisinin as a function of the concentration at which the
parasitemia is 90 percent suppressed (SD.sub.90) was reported by D. L.
Klayman, "Qinghaosu (Artemisinin): An Antimalarial
Drug from China," Science 228:1049-1055 (1985). Dr. Klayman reported
that the olefinic compound III is inactive against P. berghei-infected
mice, whereas the dihydroartemisinin condensation by-product (II-7) has
an SD.sub.90 of 10 mg/Kg in P.
berghei-infected mice. Thus, the dihydroartemisinin ether dimer proved
to be less potent than artemisinin, which has an SD.sub.90of 6.20
mg/Kg. Following, in order of their overall antimalarial efficacy, are
the three types of derivatives of
dihydroartemisinin (II-1) that have been produced:
(artemisinin)<ethers (II, R.dbd.alkyl)<esters [II,
R.dbd.C(.dbd.O)-alkyl or -aryl]<carbonates [II, R.dbd.C
(.dbd.O)O-alkyl or -aryl].
Other rational design of structurally simpler analogs of
artemisinin has led to the synthesis of various trioxanes, some of
which possess excellent antimalarial activity. Posner, G. H., et al.,
reported the chemistry and biology of a series of
new structurally simple, easily prepared, racemic 1,2,4-trioxanes
(disclosed in U.S. Pat. No. 5,225,437 and incorporated herein by
reference) that are tricyclic (lacking the lactone ring present in
tetracyclic artemisinin I) and that are derivatives of
trioxane alcohol IV
##STR00004## having the relative stereochemistry shown above.
Especially attractive features of trioxane alcohol IV are the
following: (1) its straightforward and easy preparation from cheap and
readily available starting materials, (2) its
availability on gram scale, and (3) its easy one-step conversion, using
standard chemical transformations, into alcohol derivatives such as
esters and ethers, without destruction of the crucial trioxane
framework. See, Posner, G. H., et al., J Med. Chem., 35:2459-2467
(1992), incorporated herein by reference. The complete chemical
synthesis of artemisinin and a variety of other derivatives is reviewed
by Sharma, R. P., et al., Heterocycles, 32(8):1593-1638 (1991), and is
incorporated herein by
reference.
Metabolic studies by Baker, et al., demonstrated that
.beta.-arteether (II-3), one of the antimalarial derivatives discussed
previously, was rapidly converted by rat liver microsomes into
dihydroartemisinin (II-1). See Baker, J. K., et al.,
Biol. Mass. Spect., 20:609-628 (1991). This finding and the fact that
the most effective artemisinin derivatives against malaria have been
ethers or esters of (II-1) suggest that they were prodrugs for (II-1).
The controlled slow formation of (II-1),
however, is not desirable in view of its short half-life in plasma
(less than two hours) and relatively high toxicity.
Unfortunately C-10 acetal derivatives are often unstable (i.e.
easily hydrolyzed) in water. Therefore making hydrolytically stable
C-10 non-acetal carba-derivatives has become a high priority
internationally.
Over the past thirty years only a few drugs isolated from
higher plants have yielded clinical agents, the outstanding examples
being vinblastine and vincristine from the Madagascan periwinkle,
Catharanthus roseus, etoposide, the semi-synthetic
lignan, from Mayapple Podophyllum peltatum and the diterpenoid taxol,
commonly referred to as paclitaxel, from the Pacific yew, Taxus
brevifolia. Of these agents, paclitaxel is the most exciting, recently
receiving approval by the Food and Drug
Administration for the treatment of refractory ovarian cancer. Since
the isolation of artemisinin, there has been a concerted effort by
investigators to study other therapeutic applications of artemisinin
and its derivatives.
National Institutes of Health reported that artemisinin is
inactive against P388 leukemia. See NCI Report on NSC 369397 (tested on
25 Oct. 1983). Later anticancer studies that have been conducted on
cell line panels consisting of 60 lines
organized into nine, disease-related subpanels including leukemia,
non-small-cell lung cancer, colon, CNS, melanoma, ovarian, renal,
prostate and breast cancers, further confirm that artemisinin displays
very little anticancer activity. A series of
artemisinin-related endoperoxides were tested for cytotoxicity to
Ehrlich ascites tumor (EAT) cells using the microculture tetrazolum
(MTT) assay, H. J. Woerdenbag, et al., "Cytotoxicity of
Artemisinin-Related Endoperoxides to Ehrlich Ascites Tumor
Cells," Journal of Natural Products, 56(6):849-856 (1993). The MTT
assay, used to test the artemisinin-related endoperoxides for
cytotoxicity, is based on the metabolic reduction of soluble
tetrazolium salts into insoluble colored formazan products by
mitochondrial dehydrogenase activity of the tumor cells. As parameters
for cytotoxicity, the IC.sub.50 and IC.sub.80 values, the drug
concentrations causing respectively 50% and 80% growth inhibition of
the tumor cells, were used. Artemisinin (I) had
an IC.sub.50 value of 29.8 .mu.M. Derivatives of dihydroartemisinin
(II-1) being developed as antimalarial drugs (artemether (II-2),
arteether (III-3), sodium artesunate (II-4), artelinic acid (II-5) and
sodium artelinate (II-6)), exhibited a somewhat
more potent cytotoxicity. Their IC.sub.50 values ranged from 12.2 .mu.M
to 19.9 .mu.M. The dihydroartemisinin condensation by-product dimer
(II-7), disclosed previously by M. Cao, et a., 1984, was the most
potent cytotoxic agent, its IC.sub.50 being
1.4 .mu.M. At this drug concentration the condensation by-product
(II-7) is approximately twenty-two times more cytotoxic than
artemisinin and sixty times more cytotoxic than dihydroartemisinin
(II-1), the parent compound.
While artemisinin and its related derivatives (II 1-6)
discussed above demonstrated zero to slight antiproliferative and
antitumor activity, it has been discovered that a class of artemisinin
dimer compounds exhibits antiproliferative and
antitumor activities that are, in vitro, equivalent to or greater than
known antiproliferative and antitumor agents. See, U.S. Pat. No.
5,677,468 incorporated herein by reference. Unfortunately, while the in
vitro results of these artemisinin
compounds are encouraging these compounds do not appear to have
significant antitumor activity on the treatment of tumor cells in mice.
There is still a need, therefore, to develop methods for the
formation of hydrolytically stable C-10 non-acetal carba-derivatives
and structural analogs thereof having antimalarial, and
antiproliferative and antitumor activities that are
equivalent to or greater than those of known antimalarial, and
antiproliferative and antitumor agents, respectively.
SUMMARY OF THE INVENTION
Accordingly, this invention provides a class of artemisinin
related dimers which demonstrate antimalarial and antitumor activities.
More specifically, this invention provides a class of trioxane
dimers which demonstrate antimalarial and antitumor activities and that
are considerably more stable toward hydrolysis than artemether and
related C-10 ethers and esters.
This invention further provides artemisinin dimers to be used
clinically as chemotherapeutic antimalarial and anticancer drugs.
This invention further provides artemisinin C-10-acetal
derivatives for comparisson to the corresponding dimers, and to be used
clinically as chemotherapeutic antimalarial drugs.
This invention further provides a C-10-carba trioxane dimer
that is easily transformed in one additional step into different
dimers.
This invention further provides water-soluble carboxylic acid
dimers that are thermally stable, that are more orally efficacious
antimalarials than either artelinic acid or clinically used sodium
artesunate, and that have potent and selective
anticancer activities.
Additional objects, advantages and novel features of this
invention shall be set forth in part in the description and examples
that follow, and in part will become apparent to those skilled in the
art upon examination of the following
specification or may be learned by the practice of the invention. The
objects and advantages of the invention may be realized and attained by
means of the instrumentalities, combinations, compositions, and methods
particularly pointed out in the
appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and form a
part of the specification, illustrate the preferred embodiments of the
present invention, and together with the description serve to explain
the principles of the invention.
In the drawings, FIGS. 7-15, the horizontal axis depicts
various dilutions of the test compound, ranging from 10.sup.-4 to
10.sup.-9 molar, that were exposed to the specified cancer cell lines.
The vertical axis (percentage growth) depicts the
growth of the specified cancer cell line when exposed to a specific
concentration of the tested compound as compared to the growth of the
same cancer cell line not exposed to any compound.
In the Drawings:
FIG. 1 schematically depicts
the method of converting artemisinin I into C-10 acetate 2 of the
present invention.
FIG. 2 schematically depicts
the method of converting C-10
acetate 2 into C-10 non-acetal trioxane dimer 3 of the present
invention.
FIG. 3 schematically depicts
the method of converting C-10
non-acetal trioxane dimer 3 of the present invention into bis-trioxane
primary alcohol 4 of the present invention.
FIG. 4 schematically depicts
the method of converting C-10
non-acetal trioxane dimer 3 of the present invention into bis-trioxane
vicinal diol 5 of the present invention.
FIG. 5 schematically depicts
the method of converting C-10
non-acetal trioxane dimer 3 of the present invention into bis-trioxane
epoxide 6 of the present invention.
FIG. 6 schematically depicts
the method of converting C-10
non-acetal trioxane dimer 3 of the present invention into bis-trioxane
ketone 7 of the present invention.
FIG. 7a depicts the dose
response curves generated by exposing
various leukemia cancer cell lines to various concentrations of
paclitaxel.
FIG. 7b depicts the dose
response curves generated by exposing
various leukemia cancer cell lines to various concentrations of
artemisinin.
FIG. 7c depicts the dose
response curves generated by exposing
various leukemia cancer cell lines to various concentrations of the
bis-trioxane primary alcohol 4 of the present invention.
FIG. 7d depicts the dose
response curves generated by exposing
various leukemia cancer cell lines to various concentrations of the
bis-trioxane vicinal diol 5 of the present invention.
FIG. 7e depicts the dose
response curves generated by exposing
various leukemia cancer cell lines to various concentrations of the
bis-trioxane primary succinate monoester 8a of the present invention.
FIG. 7f depicts the dose
response curves generated by exposing
various leukemia cancer cell lines to various concentrations of the
succinate ester 9 of the present invention.
FIG. 7g depicts the dose
response curves generated by exposing
various leukemia cancer cell lines to various concentrations of the
bis-trioxane .beta.-hydroxysulfone benzoic acid 10c of the present
invention.
FIG. 7h depicts the dose
response curves generated by exposing
various leukemia cancer cell lines to various concentrations of the
bis-trioxane tertiary alcohol benzoic acid 11b of the present
invention.
FIG. 7i depicts the dose
response curves generated by exposing
various leukemia cancer cell lines to various concentrations of the
bis-trioxane O-acetic acid 12b of the present invention.
FIG. 7j depicts the dose
response curves generated by exposing
various leukemia cancer cell lines to various concentrations of the
bis-trioxane primary alcohol isonicotinate N-oxide 13 of the present
invention.
FIG. 7k depicts the dose
response curves generated by exposing
various leukemia cancer cell lines to various concentrations of the
bis-trioxane diphenyl phosphate dimer 14 of the present invention.
FIG. 8a depicts the dose
response curves generated by exposing
various non-small cell lung cancer cell lines to various concentrations
of paclitaxel.
FIG. 8b depicts the dose
response curves generated by exposing
various non-small cell lung cancer cell lines to various concentrations
of the artemisinin.
FIG. 8c depicts the dose
response curves generated by exposing
various non-small cell lung cancer cell lines to various concentrations
of the bis-trioxane primary alcohol 4 of the present invention.
FIG. 8d depicts the dose
response curves generated by exposing
various non-small cell lung cancer cell lines to various concentrations
of the bis-trioxane vicinal diol 5 of the present invention.
FIG. 8e depicts the dose
response curves generated by exposing
various non-small cell lung cancer cell lines to various concentrations
of the bis-trioxane primary succinate monoester 8a of the present
invention.
FIG. 8f depicts the dose
response curves generated by exposing
various non-small cell lung cancer cell lines to various concentrations
of the succinate ester 9 of the present invention.
FIG. 8g depicts the dose
response curves generated by exposing
various non-small cell lung cancer cell lines to various concentrations
of the bis-trioxane .beta.-hydroxysulfone benzoic acid 10c of the
present invention.
FIG. 8h depicts the dose
response curves generated by exposing
various non-small cell lung cancer cell lines to various concentrations
of the bis-trioxane tertiary alcohol benzoic acid 11b of the present
invention.
FIG. 8i depicts the dose
response curves generated by exposing
various non-small cell lung cancer cell lines to various concentrations
of the bis-trioxane O-acetic acid 12b of the present invention.
FIG. 8j depicts the dose
response curves generated by exposing
various non-small cell lung cancer cell lines to various concentrations
of the bis-trioxane primary alcohol isonicotinate N-oxide 13 of the
present invention.
FIG. 8k depicts the dose
response curves generated by exposing
various non-small cell lung cancer cell lines to various concentrations
of the bis-trioxane diphenyl phosphate dimer 14 of the present
invention.
FIG. 9a depicts the dose
response curves generated by exposing
various colon cancer cell lines to various concentrations of
paclitaxel.
FIG. 9b depicts the dose
response curves generated by exposing
various colon cancer cell lines to various concentrations of
artemisinin.
FIG. 9c depicts the dose
response curves generated by exposing
various colon cancer cell lines to various concentrations of the
bis-trioxane primary alcohol 4 of the present invention.
FIG. 9d depicts the dose
response curves generated by exposing
various colon cancer cell lines to various concentrations of the
bis-trioxane vicinal diol 5 of the present invention.
FIG. 9e depicts the dose
response curves generated by exposing
various colon cancer cell lines to various concentrations of the
bis-trioxane primary succinate monoester 8a of the present invention.
FIG. 9f depicts the dose
response curves generated by exposing
various colon cancer cell lines to various concentrations of the
succinate ester 9 of the present invention.
FIG. 9g depicts the dose
response curves generated by exposing
various colon cancer cell lines to various concentrations of the
bis-trioxane .beta.-hydroxysulfone benzoic acid 10c of the present
invention.
FIG. 9h depicts the dose
response curves generated by exposing
various colon cancer cell lines to various concentrations of the
bis-trioxane tertiary alcohol benzoic acid 11b of the present
invention.
FIG. 9i depicts the dose
response curves generated by exposing
various colon cancer cell lines to various concentrations of the
bis-trioxane O-acetic acid 12b of the present invention.
FIG. 9j depicts the dose
response curves generated by exposing
various colon cancer cell lines to various concentrations of the
bis-trioxane primary alcohol isonicotinate N-oxide 13 of the present
invention.
FIG. 9k depicts the dose
response curves generated by exposing
various colon cancer cell lines to various concentrations of the
bis-trioxane diphenyl phosphate dimer 14 of the present invention.
FIG. 10a depicts the dose
response curves generated by
exposing various CNS cancer cell lines to various concentrations of
paclitaxel.
FIG. 10b depicts the dose
response curves generated by
exposing various CNS cancer cell lines to various concentrations of
artemisinin.
FIG. 10c depicts the dose
response curves generated by
exposing various CNS cancer cell lines to various concentrations of the
bis-trioxane primary alcohol 4 of the present invention.
FIG. 10d depicts the dose
response curves generated by
exposing various CNS cancer cell lines to various concentrations of the
bis-trioxane vicinal diol 5 of the present invention.
FIG. 10e depicts the dose
response curves generated by
exposing various CNS cancer cancer cell lines to various concentrations
of the bis-trioxane primary succinate monoester 8a of the present
invention.
FIG. 10f depicts the dose
response curves generated by
exposing various CNS cancer cancer cell lines to various concentrations
of the succinate ester 9 of the present invention.
FIG. 10g depicts the dose
response curves generated by
exposing various CNS cancer cancer cell lines to various concentrations
of the bis-trioxane .beta.-hydroxysulfone benzoic acid 10c of the
present invention.
FIG. 10h depicts the dose
response curves generated by
exposing various CNS cancer cancer cell lines to various concentrations
of the bis-trioxane tertiary alcohol benzoic acid 11b of the present
invention.
FIG. 10i depicts the dose
response curves generated by
exposing various CNS cancer cancer cell lines to various concentrations
of the bis-trioxane O-acetic acid 12b of the present invention.
FIG. 10j depicts the dose
response curves generated by
exposing various CNS cancer cancer cell lines to various concentrations
of the bis-trioxane primary alcohol isonicotinate N-oxide 13 of the
present invention.
FIG. 10k depicts the dose
response curves generated by
exposing various CNS cancer cancer cell lines to various concentrations
of the bis-trioxane diphenyl phosphate dimer 14 of the present
invention.
FIG. 11a depicts the dose
response curves generated by
exposing various melanoma cancer cell lines to various concentrations
of paclitaxel.
FIG. 11b depicts the dose
response curves generated by
exposing various melanoma cancer cell lines to various concentrations
of artemisinin.
FIG. 11c depicts the dose
response curves generated by
exposing various melanoma cancer cell lines to various concentrations
of the bis-trioxane primary alcohol 4 of the present invention.
FIG. 11d depicts the dose
response curves generated by
exposing various melanoma cancer cell lines to various concentrations
of the bis-trioxane vicinal diol 5 of the present invention.
FIG. 11e depicts the dose
response curves generated by
exposing various melanoma cancer cell lines to various concentrations
of the bis-trioxane primary succinate monoester 8a of the present
invention.
FIG. 11f depicts the dose
response curves generated by
exposing various melanoma cancer cell lines to various concentrations
of the succinate ester 9 of the present invention.
FIG. 11g depicts the dose
response curves generated by
exposing various melanoma cancer cell lines to various concentrations
of the bis-trioxane .beta.-hydroxysulfone benzoic acid 10c of the
present invention.
FIG. 11h depicts the dose
response curves generated by
exposing various melanoma cancer cell lines to various concentrations
of the bis-trioxane tertiary alcohol benzoic acid 11b of the present
invention.
FIG. 11i depicts the dose
response curves generated by
exposing various melanoma cancer cell lines to various concentrations
of the bis-trioxane O-acetic acid 12b of the present invention.
FIG. 11j depicts the dose
response curves generated by
exposing various melanoma cancer cell lines to various concentrations
of the bis-trioxane primary alcohol isonicotinate N-oxide 13 of the
present invention.
FIG. 11k depicts the dose
response curves generated by
exposing various melanoma cancer cell lines to various concentrations
of the bis-trioxane diphenyl phosphate dimer 14 of the present
invention.
FIG. 12a depicts the dose
response curves generated by
exposing various ovarian cancer cell lines to various concentrations of
paclitaxel.
FIG. 12b depicts the dose
response curves generated by
exposing various ovarian cancer cell lines to various concentrations of
artemisinin.
FIG. 12c depicts the dose
response curves generated by
exposing various ovarian cancer cell lines to various concentrations of
the bis-trioxane primary alcohol 4 of the present invention.
FIG. 12d depicts the dose
response curves generated by
exposing various ovarian cancer cell lines to various concentrations of
the bis-trioxane vicinal diol 5 of the present invention.
FIG. 12e depicts the dose
response curves generated by
exposing various ovarian cancer cell lines to various concentrations of
the bis-trioxane primary succinate monoester 8a of the present
invention.
FIG. 12f depicts the dose
response curves generated by
exposing various ovarian cancer cell lines to various concentrations of
the succinate ester 9 of the present invention.
FIG. 12g depicts the dose
response curves generated by
exposing various ovarian cancer cell lines to various concentrations of
the bis-trioxane .beta.-hydroxysulfone benzoic acid 10c of the present
invention.
FIG. 12h depicts the dose
response curves generated by
exposing various ovarian cancer cell lines to various concentrations of
the bis-trioxane tertiary alcohol benzoic acid 11b of the present
invention.
FIG. 12i depicts the dose
response curves generated by
exposing various ovarian cancer cell lines to various concentrations of
the bis-trioxane O-acetic acid 12b of the present invention.
FIG. 12j depicts the dose
response curves generated by
exposing various ovarian cancer cell lines to various concentrations of
the bis-trioxane primary alcohol isonicotinate N-oxide 13 of the
present invention.
FIG. 12k depicts the dose
response curves generated by
exposing various ovarian cancer cell lines to various concentrations of
the bis-trioxane diphenyl phosphate dimer 14 of the present invention.
FIG. 13a depicts the dose
response curves generated by
exposing various renal cancer cell lines to various concentrations of
paclitaxel.
FIG. 13b depicts the dose
response curves generated by
exposing various renal cancer cell lines to various concentrations of
artemisinin.
FIG. 13c depicts the dose
response curves generated by
exposing various renal cancer cell lines to various concentrations of
the bis-trioxane primary alcohol 4 of the present invention.
FIG. 13d depicts the dose
response curves generated by
exposing various renal cancer cell lines to various concentrations of
the bis-trioxane vicinal diol 5 of the present invention.
FIG. 13e depicts the dose
response curves generated by
exposing various renal cancer cell lines to various concentrations of
the bis-trioxane primary succinate monoester 8a of the present
invention.
FIG. 13f depicts the dose
response curves generated by
exposing various I renal cancer cell lines to various concentrations of
the succinate ester 9 of the present invention.
FIG. 13g depicts the dose
response curves generated by
exposing various renal cancer cell lines to various concentrations of
the bis-trioxane .beta.-hydroxysulfone benzoic acid 10c of the present
invention.
FIG. 13h depicts the dose
response curves generated by
exposing various renal cancer cell lines to various concentrations of
the bis-trioxane tertiary alcohol benzoic acid 11b of the present
invention.
FIG. 13i depicts the dose
response curves generated by
exposing various renal cancer cell lines to various concentrations of
the bis-trioxane O-acetic acid 12b of the present invention.
FIG. 13j depicts the dose
response curves generated by
exposing various renal cancer cell lines to various concentrations of
the bis-trioxane primary alcohol isonicotinate N-oxide 13 of the
present invention.
FIG. 13k depicts the dose
response curves generated by
exposing various renal cancer cell lines to various concentrations of
the bis-trioxane diphenyl phosphate dimer 14 of the present invention.
FIG. 14a depicts the dose
response curves generated by
exposing various prostate cancer cell lines to various concentrations
of paclitaxel.
FIG. 14b depicts the dose
response curves generated by
exposing various prostate cancer cell lines to various concentrations
of the bis-trioxane primary alcohol 4 of the present invention.
FIG. 14c depicts the dose
response curves generated by
exposing various prostate cancer cell lines to various concentrations
of the bis-trioxane vicinal diol 5 of the present invention.
FIG. 14d depicts the dose
response curves generated by
exposing various prostate cancer cell lines to various concentrations
of the bis-trioxane primary succinate monoester 8a of the present
invention.
FIG. 14e depicts the dose
response curves generated by
exposing various prostate cancer cell lines to various concentrations
of the succinate ester 9 of the present invention.
FIG. 14f depicts the dose
response curves generated by
exposing various prostate cancer cell lines to various concentrations
of the bis-trioxane .beta.-hydroxysulfone benzoic acid 10c of the
present invention.
FIG. 14g depicts the dose
response curves generated by
exposing various prostate cancer cell lines to various concentrations
of the bis-trioxane tertiary alcohol benzoic acid 11b of the present
invention.
FIG. 14h depicts the dose
response curves generated by
exposing various prostate cancer cell lines to various concentrations
of the bis-trioxane O-acetic acid 12b of the present invention.
FIG. 14i depicts the dose
response curves generated by
exposing various prostate cancer cell lines to various concentrations
of the bis-trioxane primary alcohol isonicotinate N-oxide 13 of the
present invention.
FIG. 14j depicts the dose
response curves generated by
exposing various prostate cancer cell lines to various concentrations
of the bis-trioxane diphenyl phosphate dimer 14 of the present
invention.
FIG. 15a depicts the dose
response curves generated by
exposing various breast cancer cell lines to various concentrations of
paclitaxel.
FIG. 15b depicts the dose
response curves generated by
exposing various breast cancer cell lines to various concentrations of
the bis-trioxane primary alcohol 4 of the present invention.
FIG. 15c depicts the dose
response curves generated by
exposing various breast cancer cell lines to various concentrations of
the bis-trioxane vicinal diol 5 of the present invention.
FIG. 15d depicts the dose
response curves generated by
exposing various breast cancer cell lines to various concentrations of
the bis-trioxane primary succinate monoester 8a of the present
invention.
FIG. 15e depicts the dose
response curves generated by
exposing various breast cancer cell lines to various concentrations of
the succinate ester 9 of the present invention.
FIG. 15f depicts the dose
response curves generated by
exposing various breast cancer cell lines to various concentrations of
the bis-trioxane .beta.-hydroxysulfone benzoic acid 10c of the present
invention.
FIG. 15g depicts the dose
response curves generated by
exposing various breast cancer cell lines to various concentrations of
the bis-trioxane tertiary alcohol benzoic acid 11b of the present
invention.
FIG. 15h depicts the dose
response curves generated by
exposing various breast cancer cell lines to various concentrations of
the bis-trioxane O-acetic acid 12b of the present invention.
FIG. 15i depicts the dose
response curves generated by
exposing various breast cancer cell lines to various concentrations of
the bis-trioxane primary alcohol isonicotinate N-oxide 13 of the
present invention.
FIG. 15j depicts the dose
response curves generated by
exposing various breast cancer cell lines to various concentrations of
the bis-trioxane diphenyl phosphate dimer 14 of the present invention.
FIG. 16 schematically depicts
the method of converting
bis-trioxane primary alcohol 4 into bis-trioxane primary succinate
monoester 8a of the present invention.
FIG. 17 schematically depicts
the method of converting
bis-trioxane vicinal diol 5 into the tertiary alcohol primary succinate
ester 9 of the present invention.
FIG. 18 schematically depicts
the method of converting
bis-trioxane epoxide 6 into bis-trioxane .beta.-hydroxysulfide ester
10a, sulfide to sulfone oxidation gave bis-trioxane
.beta.-hydroxysulfone ester 10b that was saponified into bis-trioxane
.beta.-hydroxysulfone benzoic acid 10c of the present invention.
FIG. 19 schematically depicts
the method of converting
bis-trioxane ketone 7 into bis-trioxane styryl tertiary alcohol 11a and
bis-trioxane tertiary alcohol benzoic acid 11b of the present
invention.
FIG. 20 schematically depicts
the method of converting primary
alcohol 4 to the bis-trioxane O-allyl ether 12a and bis-trioxane
O-acetic acid 12b of the present invention.
FIG. 21 schematically depicts
the method of converting primary
alcohol 4 to the bis-trioxane primary alcohol isonicotinate 8b of the
present invention.
FIG. 22 schematically depicts
the method of converting primary
alcohol 4 to the bis-trioxane primary alcohol isonicotinate N-oxide 13
of the present invention.
FIG. 23 schematically depicts
the method of converting primary
alcohol 4 to the bis-trioxane primary alcohol nicotinate N-oxide 15 of
the present invention.
FIG. 24 schematically depicts
the method of converting primary
alcohol 4 to the bis-trioxane phosphonic acid monoester 16 of the
present invention.
FIG. 25 schematically depicts
the method of converting primary
alcohol 4 to the bis-trioxane diphenyl phosphate 14 of the present
invention.
FIG. 26 schematically depicts
the method of converting
bis-trioxane ketone 7 to the bis-trioxane secondary alcohol 17 of the
present invention.
FIG. 27 schematically depicts
the method of converting
bis-trioxane vicinal diol 5 to the bis-trioxane vicinal diol
isonicotinate N-oxide 18 of the present invention.
FIG. 28 schematically depicts
the method of converting
bis-trioxane vicinal diol 5 to the bis-trioxane isobutyric acid 19 of
the present invention.
FIG. 29 schematically depicts
the method of converting
bis-trioxane vicinal diol 5 to the bis-trioxane .beta.-hydroxy O-allyl
ether 20 and then on to the bis-trioxane .beta.-hydroxy O-acetic acid
21 of the present invention.
FIG. 30 schematically depicts
the method of converting
bis-trioxane primary alcohol 4 to the bis-trioxane primary alcohol
picolinate 22 of the present invention.
FIG. 31 schematically depicts
the method of converting
bis-trioxane vicinal diol 5 to the bis-trioxane vicinal diol nicotinate
N-oxide 23 of the present invention.
FIG. 32 schematically depicts
the method of converting
bis-trioxane secondary alcohol 17 to the bis-trioxane secondary alcohol
isonicotinate N-oxide 24 of the present invention.
FIG. 33 schematically depicts
the method of converting
bis-trioxane secondary alcohol 17 to the bis-trioxane secondary alcohol
nicotinate N-oxide 25 of the present invention.
FIG. 34 schematically depicts
the method of converting
bis-trioxane primary alcohol 4 to the bis-trioxane primary alcohol
diethyl phosphoric acid triester 26 of the present invention.
FIG. 35 schematically depicts
the method of converting
bis-trioxane primary alcohol 4 to the bis-trioxane primary alcohol
dimethyl phosphoric acid triester 27 of the present invention.
FIG. 36 schematically depicts
the method of converting
bis-trioxane primary alcohol 4 to the bis-trioxane primary alcohol
p-trifluoromethylbenzoate 28 of the present invention.
FIG. 37 schematically depicts
the method of converting
bis-trioxane primary alcohol 4 to the bis-trioxane primary alcohol
3,5-ditrifluoromethylbenzoate 29 of the present invention.
FIG. 38 schematically depicts
the method of converting
bis-trioxane primary alcohol 4 to the bis-trioxane primary alcohol
dimethylgylcinate 30 of the present invention.
FIG. 39 schematically depicts
the method of converting artemisinin 1 to the dihydroartemisinin 31 of
the present invention.
FIG. 40 schematically depicts
the method of converting
dihydroartemisinin 31 to the .alpha.-dihydroartemisinin
dimethylglycinate 32 of the present invention.
FIG. 41 schematically depicts
the method of converting
dihydroartemisinin 31 to the .alpha.-dihydroartemisinin isonicotinate
N-oxide 33 of the present invention.
FIG. 42 schematically depicts
the method of converting
bis-trioxane ketone 7 to the bis-trioxane allyl tertiary alcohol 34 and
the method of converting bis-trioxane allyl tertiary alcohol 34 to the
bis-trioxane tertiary alcohol carboxylic acid 35
of the present invention.
FIG. 43 schematically depicts
the method of converting
bis-trioxane primary alcohol 4 to the bis-trioxane primary alcohol
methyl carbonate 36 and the method of converting bis-trioxane primary
alcohol 4 to the bis-trioxane primary alcohol ethyl
carbonate 37 of the present invention.
FIG. 44 schematically depicts
the method of converting
bis-trioxane ketone 7 to the bis-trioxane tertiary alcohol methyl
sulfonate 38, the method of converting bis-trioxane ketone 7 to the
bis-trioxane bis-trioxane tertiary alcohol isopropyl
sulfonate 39 and the method of converting bis-trioxane ketone 7 to the
bis-trioxane tertiary alcohol N,N-dimethylsulfonamide 40 of the present
invention.
FIG. 45 schematically depicts
the method of converting
bis-trioxane vicinal diol 5 to the bis-trioxane vicinal diol cyclic
carbonate 41 and the method of converting bis-trioxane vicinal diol 5
to the bis-trioxane vicinal diol cyclic sulfate 42 of
the present invention.
FIG. 46 schematically depicts
the method of converting
bis-trioxane epoxide 6 to the bis-trioxane tertiary alcohol pyridine
sulfide 43 of the present invention.
FIG. 47 schematically depicts
the method of converting
bis-trioxane ketone 7 to the bis-trioxane ketone O-TMS cyanohdrin 44
and the method of converting bis-trioxane ketone 7 to the bis-trioxane
tertiary alcohol nitrile 45 of the present
invention.
FIG. 48 schematically depicts
the method of converting
bis-trioxane ketone 7 to the bis-trioxane methyl enol ether 46 of the
present invention.
FIG. 49 schematically depicts
the method of converting
bis-trioxane methyl enol ether 46 to the bis-trioxane aldehyde 47 of
the present invention.
FIG. 50 schematically depicts
the method of converting
bis-trioxane aldehyde 47 to the bis-trioxane aniline 48 of the present
invention.
FIG. 51 schematically depicts
the method of converting
bis-trioxane primary alchol 4 and bis-trioxane diol 5 to a number of
compounds according to the present invention. In cases where the
derivatization of bis-trioxane primary alcohol 4 is
shown, conversion of bis-trioxane secondary alcohol 17 and bis-trioxane
diol 5 to their corresponding analogs is also in accordance with the
present invention.
FIG. 52 schematically depicts
the method of converting a
number of compounds of the present invention to ten other compounds
that can be synthesized according to the present invention.
FIG. 53 schematically depicts
the method of converting
bis-trioxane aldehyde 47 to a range of substituted and unsubstituted
amine/amide derivatives of the current invention.
FIG. 54 represents other
compounds that can be synthesized according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED
EMBODIMENT
The present invention provides a direct method for converting a
novel C-10-carba trioxane dimer in one step into a number of different
dimers, all of which are hydrolytically stable. The resulting trioxane
dimers may then be further reacted to
form 3-carbon atom linked, oxygenated dimers. These C-10 non-acetal
derivatives of natural trioxane artemisinin have high in vitro
antimalarial and antitumor activities.
In general, the compound of the present invention includes
resolved enantiomers, diastereomers, solvates and pharmaceutical
acceptable salts thereof, and may be illustrated as follows:
##STR00005##
Where if R.sub.1 is hydrogen or OH then R.sub.2 is AX, and if
R.sub.2 is hydrogen or OH then R.sub.1 is AX, and A may be absent or A
may be any alkyl or aryl group where X is hydrogen, a phosphate group,
a phosphonic acid derivative group, an
alcohol group, a carboxylic acid group, an ether group, an ester group,
a nitrile group, a sulfone group, a sulfide group, an amino acid
derivative group, an amine group, and amide group, an aldehyde group,
or an aromatic group.
The alcohol group may be represented by --R.sup.3OH, where
R.sup.3 is a straight chained or branched alkyl group having 1 to 5
carbon atoms. The carboxylic acid group may be represented by
--R.sup.4COOH, where R.sup.4 is at least one saturated
or unsaturated alkyl group, an ester group, an ether group or a
combintion thereof. When R.sup.4 is an ester group, it may be
represented by --R.sup.5COO--, where R.sup.5 is bonded to the
carboxylic acid group and has 0 to 5 carbon atoms. When R.sup.4
is an ether group, it may be represented by R.sup.6--O--R.sup.7 wherein
R.sup.6 and R.sup.7 are, independently, an alkyl or allyl group having
0 to 5 carbon atoms. The aromatic group may be represented by
Ar--(R.sup.8).sub.m, where Ar represents a
benzene ring, and m is 1 or 2, and R.sup.8 may represent
--CH.dbd.CH.sub.2, or --COOH. The ester group may be represented by
--CR.sup.9, where R.sup.9 is an ester of nicotinic acid, an ester of
isonicotinic acid, or the ester group is represented by
--CO(C.dbd.O)R.sup.9a, where R.sup.9a is Ph(CY.sub.3).sub.o, where o is
1 or 2, and Y may be, independently, H, F, Cl, Br, or 1, or where
R.sup.9a is a substituted heterocyclohexane compound. The phosphonic
acid derivative group may be represented by
--CO--P(R.sup.10)OOH, where R.sup.10 is an alkyl group having 0 to 5
carbon atoms. The phosphate group is --COP(O)(OR.sup.11).sub.2, where
R.sup.11 is an alkyl group having 0 to 5 carbon atoms, or a phenyl
group. The nitrile group is R.sup.12CN, where
R.sup.12 is an alkyl group having 0 to 5 carbon atoms. The sulfone
group may be represented by --CS(.dbd.O).sub.2R.sup.13, wherein
R.sup.13 is --N(CH.sub.3).sub.2, --OR.sup.14, or --Ph--COOR.sup.14,
where R.sup.14 is H, CH.sub.3, or
--CH(CH.sub.3).sub.2. The sulfide group may be represented by
--CSR.sup.15, where R.sup.15 is pyridine or --Ph--COOR.sup.16, where
R.sup.16 is H or CH.sub.3. The amino acid derivative group is
--COC(.dbd.O)CN(R.sup.17).sub.2, where each R.sup.17 group
is, independently, H or CH.sub.3. The amine group may be represented by
--CN(R.sup.18).sub.2, where each R.sup.18 group is, independently, H,
an alkyl group, or a phenyl group. The ether group may be represented
by --C--O--CR.sup.19, where R.sup.19 is
a substituted pyridine. The amide group is
--(C.dbd.O)N(R.sup.20).sub.2, or --CH.sub.2(C.dbd.O)N(R.sup.20).sub.2
where each R.sup.20 is, independently, H or
--CH.sub.2CH.sub.2N(CH.sub.3).sub.2.
The compound of the present invention may also be illustrated as:
formula:
##STR00006## where D forms a heterocyclic ring having 3 to 5
atoms. For example, the heterocyclic ring may be a 3-membered ring and
one of the atoms in the ring is oxygen. The heterocyclic ring may also
be a 5-membered ring and two of the
atoms in the ring are oxygen, and the ring may also be substituted with
an oxygen atom and another atom in the 5-membered ring may be a sulfur
or phosphorus atom. In another example, the 5-membered ring may also be
substituted with 1 or 2 oxygen atoms
bonded to the sulfur atom.
The compound of the present invention may further be illustrated as:
##STR00007## where where E is H, O, NR, CH.sub.2 or S wherein R may be
hydrogen, alkyl, aryl or any other substituent.
In general, the first step of the preferred process of the
present invention, shown in FIG. 1, conversion of artemisinin (I) into
.alpha.-dihydroartemisinin acetate (2), is accomplished by using an
effective amount of a hydride nucleophile in
combination with an acetylating agent which chemoselectively reacts at
the C-10 position of the artemisinin skeleton without disrupting the
O--O bond in this trioxane. Effective nucleophilic hydride reagents
include, but are not limited to sodium
borohydride, and DIBAL. The relative amounts of the various possible
nucleophilic hydride reagents depends upon the concentration employed
and other conditions of the reaction. Various amounts of the
nucleophilic reagents can be employed, but generally
it should be present in the range of 1.0 to 1.5 molar equivalents of
nucleophilic hydride per molar equivalent of artemisinin for the
reaction to proceed to completion. Effective acetylating agents
include, but are not limited to acetyl chloride and
acetic anhydride. The relative amounts of the various possible
acetylating agents depends upon the concentration employed and other
conditions of the reaction. Various amounts of the acetylating agents
can be employed, but generally it should be
present in the range of 1.0 to 1.5 molar equivalents of acetylating
agent per molar equivalent of dihydroartemisinin for the reaction to
proceed to completion.
The next step, shown in FIG. 2, in the production of the novel
meso trioxane dimer 3 involves the substitution of the acetoxy group
from the C-10 acetate 2 product to form the meso trioxane dimer 3
product. Inspiration for this bis-allylation of
C-10 acetate 2 was based on the pioneering trioxane mono-allylations of
Ziffer (Pu, Y. M.; Ziffer, H., Synthesis and Antimalarial Activities of
12.beta.-Allyldeoxoartemisinin. J. Med. Chem. 1995, 38, 613-616) and
O'Neill (O'Neill, et al., J. Med. Chem. 1999, 42, 5487-5493; and
O'Neill, P. M., et al., J. Chem. Soc., Perkin Trans. 2001, 1,
2682-2689.) using allylsilane and based also on allylic bis-silane
chemistry, see Rychnovsky, S. D., et. al., Tetrahedron Lett. 1999, 40,
41-44. The requisite
allylic bis-silane is easily prepared in one step from the
corresponding commercial allylic dichloride (Shown in FIG. 2); in the
presence of fresh tin tetrachloride, the allylic bis-silane converts
acetate 2 on gram scale into meso dimer 3, characterized
by .sup.1H NMR spectroscopy as done before in structurally related
trioxanes. This double substitution reaction undoubtedly proceeds
sequentially via initial monoallylation, producing an intermediate C-10
allylic silane that then reacts with another
molecule of trioxane acetate 2 to form the product dimer 3. This new
dimer 3, with an unsaturated 3-carbon atom linker between the two
trioxane units, is stable in air and light at room temperature for at
least six months, and its preparation on much
larger industrial scale should be feasible.
In contrast to most simple peroxides that are easily cleaved
by reducing agents and by reactive organometallics, the peroxide
linkage in artemisinin-like trioxanes is relatively robust. Therefore,
several different chemical transformations
chemospecifically involving only the linker isobutylene carbon-carbon
double bond in dimer 3 may be performed and are discussed in further
detail below.
Borane reduction and in situ oxidation produced bis-trioxane
primary alcohol 4, shown in FIG. 3. Dihydroxylation using osmium
tetroxide gave bis-trioxane vicinal diol 5, shown in FIG. 4.
Dimethyldioxirane formed bis-trioxane epoxide 6, shown in
FIG. 5. Oxidative cleavage using catalytic osmium tetroxide and Oxone
led to bis-trioxane ketone 7, shown in FIG. 6. Bis-Trioxanes 4-7 are
stable even when heated neat in air for 24 h at 60.degree. C.; .sup.1H
NMR spectroscopy showed less than 5%
decomposition under these accelerated aging conditions.
To illustrate further the chemical inertness of the peroxide
unit in these trioxane dimers, and especially to generate some
water-soluble dimers that can be easily administered in vivo, each
dimer 4-7 was converted into a carboxylic acid (FIGS.
16-20). Primary alcohol 4 opened succinic anhydride to form
bis-artesunate 8a in high yield, see FIG. 16. Likewise, diol 5 opened
succinic anhydride to produce the tertiary alcohol primary succinate
ester 9, see FIG. 17. Epoxide 6 reacted
chemospecifically with a benzenethiol in the presence of
chromatographic alumina to give .beta. hydroxysulfide 10a in high
yield; sulfide to sulfone oxidation gave dimer benzoate ester 10b that
was saponified into benzoic acid 10c, see FIG. 18. Ketone
7 underwent chemospecific addition of styryllithium to afford styryl
tertiary alcohol 11a; oxidative cleavage of the styrene double bond
produced benzoic acid 11b, see FIG. 19. Primary alcohol 4 was allylated
and the allyl double bond was oxidatively
cleaved to generate acetic acid 12b, see FIG. 20.
Each of these new carboxylic acid dimers is at least as
soluble in water at pH 7.4 as is the antimalarial drug candidate
artelinic acid, and tertiary alcohol primary succinate ester 9 is close
to 30 times more water-soluble than artelinic acid,
and phosphonic acid 16 is even more water soluble than succinate ester
9. Trioxane dimer carboxylic acids 8a-10c and 12b are stable in air
even at 60.degree. C. for 24 hours.
Primary alcohol 4 may also be transformed into a variety of
other compounds as shown in FIGS. 21-25, 28, 30, 34-38 and 43.
Likewise, diol 5 may be converted into a variety of compounds as shown
in FIGS. 27, 29, 31 and 45. Additionally,
secondary alcohol 17 may be transformed into a variety of compounds as
shown in FIGS. 32 and 33. Likewise, ketone 7 may be converted into a
variety of compounds as shown in FIGS. 42, 44, 47 and 48 and epoxide 6
may be reacted further as shown in FIG.
46. Finally, dimer 3 may be converted to a variety of compounds as
shown in FIGS. 51, 52 and 53.
Determination of Antimalarial Activity
To determine the antimalarial effect of various dimers of the
present invention, screening assays were performed against
chloroquine-sensitive P. falciparum (NF54), according to the method
described below, and their IC.sub.50 values are included
in Table 1.
Activity was determined by measuring the incorporation of
[.sup.3H]hypoxanthine, by the methods of DesJardins and Milhous, with
the following modifications, see Desjardins, R. E.; Canfield, C. J.;
Haynes, J. D.; Chulay, J. D., Antimicrob. Agents
Chemother., 16:710 (1979); Milhous, W. K.; Weatherly, N. F.; Bowdre, J.
H.; Desjardins, R., Antimicrob. Agents Chemother., 27:525 (1985).
Chloroquine-sensitive P. falciparum (NF54 strain) were maintained in a
2.4% suspension of type O.sup.+ human
erythrocytes (obtained weekly from a rotating pool of screened healthy
volunteers) in RPMI 1640 (Gibco BRL # 13200-076), supplemented with 25
mM N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES;
Calbiochern #391338), 27 mM NaHCO.sub.3 (Gibco
BRL # 11810-025), and 10% heat-inactivated human type O.sup.+ serum
(Interstate Blood Bank, Inc.), under 3% O.sub.2, 4% CO.sub.2, and 93%
N.sub.2. Parasitemia was maintained at 0.05-3% and doubling time at
approximately 15 hours by twice weekly change
of medium and replenishment with fresh erythrocytes.
Stock solutions (approximately 2.5 mg/mL of HPLC-purified or
recrystallized test compound) were prepared in dimethyl sulfoxide
(DMSO; Sigma-Aldrich #27,043-1). DMSO solutions were diluted 500-fold
in medium, serially diluted in 0.2% DMSO in
medium (to maintain constant solvent concentration), then 100 .mu.L
aliquots were pipetted into microtiter plate wells (Costar3595).
Provisional EC.sub.50 values were obtained in a survey of seven 5-fold
dilutions yielding final concentrations (in
triplicate) of 0.16-2500 ng/mL. Assays were later expanded to include
ten concentrations (in quadruplicate) of approximately 1.8-fold
dilutions which flank the provisional EC.sub.50. Plates included at
least 8 wells of no drug controls (4 with and 4
without DMSO) and 4 wells of uninfected erythrocytes. Parasite culture
(0.25% parasitemia in 2.4% hematocrit; 100 .mu.L per well) was added
and the plate was incubated for 48 hours prior to the addition of 25
.mu.L [.sup.3H]hypoxanthine (14.1 Ci/mmol, 1
mCi/mL in 70% ethanol, New England Nuclear NET-177, diluted to 25
.mu.Ci/mL with medium) and subsequent 20 hour incubation. Cells were
harvested (Brandel MB-48R) onto GF-C glass filters (Brandel). The
filters were washed five times with 3 mL water per
sample spot, dried under a heat lamp, and counted (Beckman Model
LS-6500) in scintillation cocktail (ICN Cytoscint).
Decays per minute (dpm) values were downloaded and analyzed
(Power Macintosh 7200/90; Microsoft Excel 5.0), to yield the mean and
standard deviation at each drug concentration. Dose-response curves
were fit to the experimental data (Delta Point
DeltaGraph 3.5.3) by means of the Marquardt algorithm, were solved for
the drug concentration that kills 50% of parasites, and were analyzed
for goodness of fit (R.sup.2 value).
TABLE-US-00001 TABLE I Antimalarial Activities in vitro.sup.a
Trioxane IC.sub.50(nM) 3 24.0 4 0.87 5 0.59 6 2.8 7 0.91 8a 2.0 8b 1.7
9 3.0 10c 2.4 11b 2.1 12b 3.2 13 0.53 14 10.0 15 0.58 16 320 17 0.66 18
0.34 19 2.4 21 4.4 23 0.40 24 0.42 25
0.31 26 0.74 27 0.48 32 1.1 33 0.81 35 2.0 36 1.7 37 2.8 38 200 40 0.73
41 0.59 42 19 48 4.8 Artemisinin 9.2 .+-. 1.7 .sup.aThe standard
deviation for each set of quadruplicates was an average of 8.6%
(.ltoreq.22%) of the mean. R.sup.2 values for the
fitted curves were .gtoreq.0.933. Artemisinin activity is mean .+-.
standard deviation of concurrent control (n = 34).
In sharp contrast to the potency of the natural trioxane
artemisinin (IC.sub.50=7.7 nm) and of the initial olefinic dimer 3
(IC.sub.50=24 nM), alcohol dimers 4 and 17, diol dimer 5 and ketone
dimer 7 all have substantially enhanced potencies,
with IC.sub.50 values below one nM. In addition, further derivitization
of these potent antimalarials has produced a number of analogs also
antimalarially active in sub-nanomolar concentrations (most notably:
pyridine N-oxides 13, 15, 18, 23, 24 and 25,
phosphoric acid triesters 26 and 27, sulfonamide 40 and cyclic
carbonate 41).
The in vivo antimalarial efficacies of water-soluble dimer
carboxylic acids 8a-10c and 12b (11b not tested), as measured in mice
according to a published protocol, are shown in Table II. In all cases,
these water-soluble dimeric trioxanes are
more efficacious than the drug candidate artelinic acid administered
intravenously (IV) and than the clinically used drug sodium artesunate
administered orally (PO). At an IV dose of 10 mg/kg of mouse body
weight, each dimeric trioxane 8a-10c and 12b
suppressed P. berghei NY malaria parasite growth considerably better
(>80%) than did artelinic acid or sodium artesunate. Neither overt
toxicity nor behavioral modification was observed due to drug
administration in any of these mouse experiments.
TABLE-US-00002 TABLE II Antimalarial Efficacies in vivo %
Parasite Trioxane Administration Supression Carboxylic Acid Route
ED.sub.50.sup.b ED.sub.90.sup.b at 10 mg/kg 8a IV 2.2 6.3 81.0 PO 9.0
15.0 79.2 12b IV 1.0 3.5 95.7 PO 6.5 17.0 46.5
Artelinic Acid IV 11.0 25.0 54.7 Sodium Artesunate PO 10.0 39.0 52.8 9
IV 2.4 11.0 83.4 PO 4.8 34.0 55.4 10c IV 2.7 10.0 83.4 PO 7.5 35.0 46.1
Artelinic Acid IV 5.6 43.0 42.4 Sodium Artesunate PO 5.5 70.0 50.9
.sup.bmg/kg .times. 4
Determination of Antitumor Activities
Growth Inhibition. To determine the growth inhibition (GI) and
cytotoxicity of dimers 4, 5, 8a, 9, 10c, 11b, 12b, 13, and 14
respectively, of the present invention, screening assays were performed
by the National Cancer Institute using a 60 cell
line panel; these activities are summarized in Tables III, IV and V
(set out below). The screening assay is performed on 96-well microtitre
plates. Relatively high initial inoculation densities are used, in
order to permit measurement of "time-zero"
values and to enhance the screen's ability to detect and provide some
differentiation between growth inhibition and cytotoxic response
parameters. The specific inoculation densities (which range from 5,000
to 40,000 cells/well) used for each cell line
are those which, for the respective line, were determined to give an
optical density signal for both the "time-zero" value (at 24 hours) and
the "no-drug" control (at 72 hours) above the noise level and within
the linear range of the end-point assay
(which measures cellular protein). The inoculated microtitre plates are
pre-incubated for 24 hours at 37.degree. C. prior to drug additions.
The five drug dilutions tested routinely range from 10.sup.-4 to
10.sup.-8 molar. Higher or lower
concentration ranges may be selected on a non-routine basis if
appropriate solubility and/or prior biological information or other
screening data so dictate. Duplicate wells are prepared for all
concentrations, (concentration is often denoted by placing
brackets around a number); "time-zero" and "no drug" controls are also
provided for each test. The minimum amount of compound required for a
one-time evaluation in the routine screen can be calculated from the
knowledge that each test requires a total
of approximately 40 ml (0.04 liter) of cell culture medium containing
the highest desired drug concentration. Thus, the amount (grams) of
sample required (assuming an upper test concentration limit of
10.sup.-4 M) is: molecular weight of
compound.times.10.sup.-4.times.0.04. After a 48 hour incubation
(37.degree. C.) with the test compound, the cells are fixed in situ to
the bottoms of the microtitre wells by addition of 50 .mu.l of either
50% trichloroacetic acid (for adherent cell
lines) or 80% trichloroacetic acid (for settled cell suspension lines),
followed by incubation for 60 minutes at 4.degree. C. The cellular
protein in each well is assayed using a sulforhodamine B (SRB) stain
procedure. Briefly, after discarding the
supernatants, the microtitre plates are washed 5 times with deionized
water and air-dried. One hundred microliters of SRB solution (0.4% w/v
in 1% acetic acid) is added to each microtitre well and incubated for
10 minutes at room temperature. Unbound
SRB is removed by washing 5 times with 1% acetic acid. The plates are
air-dried, the bound stain is solubilized with Tris buffer, and the
optical densities read at 515 nm. SRB is a bright pink anionic dye
which, in dilute acetic acid, binds
electrostatically to the basic amino acids of TCA-fixed cells.
Cryopreserved master stocks of all the lines are maintained, and
cultures used for screening are replaced from the master stock after no
more than twenty passages in the screening
laboratory. The cell line panel consists of 60 lines, organized into
nine, disease-related subpanels including leukemia, non-small-cell lung
cancer, colon, CNS, melanoma, ovarian, renal, prostate and breast
cancers.
The response parameters GI.sub.50 and LC.sub.50 are
interpolated values representing the concentrations at which the
percentage growth (PG) is +50 and -50, respectively:
GI.sub.50 is the concentration for which the PG=+50. At this
value the increase from time t.sub.zero, in the number or mass of cells
in the test well is only 50% as much as the corresponding increase in
the control well during this period of the
experiment, see Table III. A drug effect of this intensity is
interpreted as primary growth inhibition.
TGI is the concentration for which PG=0. At this value the
number or mass of cells in the well at the end of the experiment equals
the number or mass of cells in the well at time t.sub.zero, see Table
IV. A drug effect of this intensity is
regarded as cytostasis.
LC.sub.50 is the concentration for which the PG=-50. At this
value, the number or mass of cells in the test well at the end of the
experiment is half that at time t.sub.zero, see Table V. This is
interpreted as cytotoxicity.
TABLE-US-00003 TABLE III Log.sub.10GI.sub.50 Panel/Cell
Artem- Trioxane Dimers Pacli- Line isinin 4 5 8a 9 10c 11b 12b 13 14
taxel Leukemia CCRF-CEM -- -- -4.71 <-8.30 <-8.30 <-8.30 -8.07
<-8.30 5.73 &g- t;-4.30 -11.61 HL-60(TB)
-4.26 -7.78 <-8.00 <-8.30 <-8.30 <-8.30 <-8.30 &l-
t;-8.30 <-8.30 -11.57 K-562 -4.33 -7.91 <-8.00 <-8.30 -8.30
<-8.30 <-8.30 <-8.30 - <-8.30 -10.83 MOLT-4 -4.73 -7.92
<-8.00 -8.18 -5.15 -- <-8.30 -7.66 -- -11.07
RPMI-8226 >-4.00 <-8.00 -- <-8.30 <-8.30 <-8.30 -- --
<-- 8.30 <-8.30 <-13.00 SR >-4.00 <-8.00 -- -- -- -- --
-- -- -- 8.34 Non-Small Cell Lung Cancer A549/ATCC -4.17 -7.29 -7.59
-4.42 -4.86 -5.28 -5.69 >-4.30 -5.98
<-8- .30 -- EKVX >-4.00 -7.12 -- -6.90 -- -4.99 -4.79 >-4.30
-8.19 <-8.30 -- HOP-62 >-4.00 -4.92 -4.66 -6.34 -5.69 <-8.30
-6.96 -6.23 -- -4.90 -9- .67 HOP-92 >-4.00 -6.37 -4.93 -6.56
<-8.30 <-8.30 -7.43 -7.00 -8.04 &- lt;-8.30
-- NCI-H226 >-4.00 -4.82 -4.87 <-8.30 -- <-8.30 -- -- -- -- --
NCI-H23 >-4.00 -7.84 -4.83 <-8.30 <-8.30 <-8.30 -8.19
<-8.3- 0 <-8.30 <-8.30 -- NCI-H322M -- -4.97 -4.71 -5.11 -5.07
-6.03 -6.72 -5.03 -6.26 <-8.30 -10- .12
NCI-H460 >-4.00 -7.35 -5.02 <-8.30 <-8.30 <-8.30 <-8.30
<- ;-8.30 <-8.30 <-8.30 -12.16 NCI-H522 -- -7.53 -7.33
-6.16 -4.91 <-8.30 -6.54 >-4.30 -- -- <-1- 3.00 Colon Cancer
COLO 205 >-4.00 <-8.00 <-8.00 <-8.30
-- <-8.30 <-8.30 &l- t;-8.30 <-8.30 <-8.30 -11.07
HCC-2998 >-4.00 -7.45 -4.65 -- -- -- -- -- -- -- -12.34 HCT-116
-4.18 <-8.00 -4.72 <-8.30 <-8.30 <-8.30 <-8.30 <-
-8.30 <-8.30 <-8.30 <-13.00 HCT-15 >-4.00
<-8.00 -5.28 <-8.30 <-8.30 <-8.30 <-8.30 &- lt;-8.30
<-8.30 <-8.30 -6.37 HT29 >-4.00 -7.75 <-8.00 <-8.30
<-8.30 <-8.30 <-8.30 <- ;-8.30 -- -- <-13.00 KM12
>-4.00 <-8.00 <-8.00 <-8.30 <-8.30
<-8.30 <-8.30- <-8.30 <-8.30 -- -11.43 SW-620 >-4.00
<-8.00 -4.97 -- -- -- -- -- <-8.30 <-8.30 -11.60- CNS Cancer
SF-268 -- -5.40 -4.94 -7.11 -5.48 <-8.30 -7.72 -6.82 -5.29 -- --
SF-295 -- -5.59 -4.94 -- <-8.30 -- -- --
-5.21 <-8.30 -- SF-539 -- -7.05 -4.86 -5.27 -4.90 -5.19 -4.80 -4.53
<-8.30 <-8.30 -1- 1.09 SNB-19 >-4.00 -4.88 -4.82 -5.62 --
-6.72 -6.53 -6.03 -5.08 -- -8.98 SNB-75 >-4.00 -4.99 -4.53 -6.47 --
-- -7.40 -- -- -- -- U251 >-4.00 -7.27
-7.68 -8.20 -- <-8.30 <-8.30 <-8.30 <-8.3- 0 <-8.30
-11.29 Melanoma LOX IMVI -- -7.26 <-8.00 -- -- -- -- -- <-8.30
<-8.30 -11.80 MALME-3M -- -7.31 -- <-8.30 <-8.30 <-8.30
<-8.30 -- <-8.30 - -7.22 -- M14 -- -5.87
-4.59 -6.94 -- <-8.30 -7.81 -6.68 -5.81 -- -11.73 SK-MEL-2 -- -7.33
-4.94 -5.12 -4.88 -- -6.43 -5.62 -5.12 >-4.30 -9.53 SK-MEL-28
>-4.00 -4.95 -4.79 -6.09 <-8.30 -5.45 -6.40 -4.92 -5.13 --- --
SK-MEL-5 >-4.10 -7.90 -7.69 -- -- -- -- --
<-8.30 <-8.30 -- UACC-257 >-4.00 -7.31 <-8.00 -5.02 -4.89
-- -- >-4.30 -5.15 <-- 8.30 -10.30 UACC-62 >-4.00 -6.86 -- --
-- -- -- -- -8.00 <-8.30 -10.46 Ovarian Cancer IGROVI -4.31 -5.36
-4.97 -5.07 -4.97 -- -5.98 -5.06 -5.36 -5.81
-8.61 OVCAR-3 -- -7.68 -5.09 <-8.30 <-8.30 <-8.30 <-8.30
<-8.30 -- 7.75 <-8.30 -10.40 OVCAR-4 -- -5.44 -4.99 -- -- -- --
-- <-8.30 <-8.30 -5.00 OVCAR-5 >-4.00 -7.79 -4.78 <-8.30
<-8.30 <-8.30 <-8.30 <- -8.30
<-8.30 <-8.30 -9.38 OVCAR-8 >-4.00 -7.33 <-8.00 >-4.30
-5.12 -5.25 -5.26 >-4.30 -7- .69 <-8.30 -10.75 SK-OV-3 -- -4.85
-4.62 -4.89 -- -6.82 -- >-4.30 -5.13 >-4.30 -- Leukemia CCRF-CEM
-- -- -4.71 <-8.30 <-8.30 <-8.30
-8.07 <-8.30 5.73 &g- t;-4.30 -11.61 HL-60(TB) -4.26 -7.78
<-8.00 <-8.30 <-8.30 <-8.30 <-8.30 &l- t;-8.30
<-8.30 -11.57 K-562 -4.33 -7.91 <-8.00 <-8.30 -8.30 <-8.30
<-8.30 <-8.30 - <-8.30 -10.83 MOLT-4 -4.73 -7.92
<-8.00 -8.18 -5.15 -- <-8.30 -7.66 -- -11.07 RPMI-8226 >-4.00
<-8.00 -- <-8.30 <-8.30 <-8.30 -- -- <-- 8.30 <-8.30
<-13.00 SR >-4.00 <-8.00 -- -- -- -- -- -- -- -- 8.34
Non-Small Cell Lung Cancer A549/ATCC -4.17 -7.29
-7.59 -4.42 -4.86 -5.28 -5.69 >-4.30 -5.98 <-8- .30 -- EKVX
>-4.00 -7.12 -- -6.90 -- -4.99 -4.79 >-4.30 -8.19 <-8.30 --
HOP-62 >-4.00 -4.92 -4.66 -6.34 -5.69 <-8.30 -6.96 -6.23 -- -4.90
-9- .67 HOP-92 >-4.00 -6.37 -4.93 -6.56
<-8.30 <-8.30 -7.43 -7.00 -8.04 &- lt;-8.30 -- NCI-H226
>-4.00 -4.82 -4.87 <-8.30 -- <-8.30 -- -- -- -- -- NCI-H23
>-4.00 -7.84 -4.83 <-8.30 <-8.30 <-8.30 -8.19 <-8.3- 0
<-8.30 <-8.30 -- NCI-H322M -- -4.97 -4.71 -5.11
-5.07 -6.03 -6.72 -5.03 -6.26 <-8.30 -10- .12 NCI-H460 >-4.00
-7.35 -5.02 <-8.30 <-8.30 <-8.30 <-8.30 <- ;-8.30
<-8.30 <-8.30 -12.16 NCI-H522 -- -7.53 -7.33 -6.16 -4.91
<-8.30 -6.54 >-4.30 -- -- <-1- 3.00 Renal Cancer
786-0 >-4.00 -7.48 -4.87 -6.45 <-8.30 <-8.30 -7.17 -6.59 -7.81
&l- t;-8.30 -8.01 A498 >-4.00 -6.69 -4.81 -- -- -- -- -- -6.97
-7.20 -7.14 ACHN >-4.00 -7.12 <-8.00 -- -6.67 -- -- -- <-8.30
<-8.30 -- CAKI-1 -- -7.05 -4.94 -6.84 --
<-8.30 -7.74 -6.91 -7.36 <-8.30 -- RXF 393 -4.08 -4.80 -4.89
<-8.30 -7.67 <-8.30 <-8.30 <-8.30 -5- .20 -- -8.32 SN12C
-4.21 -7.46 -7.60 -- -- -- -- -- <-8.30 <-8.30 -9.53 TK-10
>-4.00 -6.60 -4.91 -6.92 <-8.30 <-8.30 -7.81
-7.22 <-8.3- 0 <-8.30 -7.89 UO-31 -4.06 -7.46 -7.38 -5.46 -5.05
-5.91 -6.78 -5.84 <-8.30 <-8.30 - -6.09 Prostate Cancer PC-3
-4.17 <-8.00 <-8.00 <-8.30 <-8.30 <-8.30 <-8.30
<- ;-8.30 <-8.30 <-8.30 -10.85 DU-145 --
-6.24 -4.83 -- -- -- -- -- -7.48 -- -9.38 Breast Cancer MCF7 >-4.00
-7.22 <-8.00 <-8.30 <-8.30 <-8.30 <-8.30 -7.- 37
<-8.30 <-8.30 -11.69 NCI/ADR-RES -- -7.45 -4.75 -5.64 -5.61 -5.73
-6.84 -6.45 -7.60 -6.07 -8.48- MDA- -4.20 -5.40
-4.99 -7.19 -- <-8.30 -- -- -7.64 <-8.30 -8.54 MB231/ATCC HS 578T
>-4.00 -4.82 -4.72 >-4.30 -4.36 -4.82 -5.15 >-4.30 <-8- .30
<-8.30 -- MDA-MB-435 -- -7.50 -- -- <-8.30 <-8.30 -8.16 -6.97
-7.62 <-8.30 - <-13.00 MDA-N
>-4.00 -7.54 -- -7.29 -- -- -- -- -- <-13.00 BT-549 -4.06 -7.11
<-8.00 -7.91 -- -6.67 -5.82 -- <-8.30 <-8.30 -- 9.31 T-47D --
<8.00 -7.23 <-8.30 -- <-8.30 <-8.30 <-8.30 <-8.- 30
-- -9.81 MG MID -- -6.87 -5.97 -7.01 -7.02
-7.57 -7.37 -6.73 -7.38 -7.79 -- Delta -4.07 1.13 2.03 1.29 1.28 -0.73
0.93 1.57 0.92 -.51 -10.15 Range 0.73 3.20 3.47 4.00 3.94 3.48 3.52
4.00 3.22 4.00 8.00
TABLE-US-00004 TABLE IV Log.sub.10TGI.sub.50 Panel/Cell
Artem- Trioxane Dimers Pacli- Line isinin 4 5 8a 9 10c 11b 12b 13 14
taxel Leukemia CCRF-CEM -- -4.66 >-4.00 >-4.30 >-4.30 -4.84
>-4.30 >-4.30 - >-4.30 >-4.30 >-4.00
HL-60(TB) >-4.00 -4.88 -- -7.61 -- <-8.30 -8.11 <-8.30 --
>-4.- 30 -4.53 K-562 >-4.00 >-4.00 >-4.00 >-4.30
>-4.30 -4.75 >-4.30 &g- t;-4.30 -- >-4.30 >-4.00 MOLT-4
>-4.00 >-4.00 >-4.00 >-4.30 >-4.30
>-4.30 >-4.- 30 >-4.30 -- -- >-4.00 RPMI-8226 >-4.00
-6.91 >-4.00 -6.19 >-4.30 -5.03 -- -- >-4.30 - >-4.30
>-4.00 SR >-4.00 -4.58 -- -- -- -- -- -- -- >-4.30 >-4.00
Non-Small Cell Lung Cancer A549/ATCC >-4.00
-4.71 -4.82 >-4.30 >-4.30 >-4.30 >-4.30 &g- t;-4.30
-4.61 >-4.30 -- EKVX >-4.00 -4.77 -- -5.47 -- -4.63 >-4.30
>-4.30 -5.08 >-4.30- -- HOP-62 >-4.00 -4.56 -4.26 >-4.30
>-4.30 -5.01 >-4.30 >-4.30- -4.91 >-4.30
-4.80 HOP-92 >-4.00 -4.65 -4.49 >-4.30 >-4.30 -5.05 >-4.30
>-4.30- -5.27 >-4.30 -- NCI-H226 >-4.00 -4.40 -4.49 -6.67 --
<-8.30 -- -- -- -- -- NCI-H23 >-4.00 -- -4.26 >-4.30 -4.65
-5.25 -4.63 >-4.30 -5.17 -- - -- NCI-H322M
-- -4.63 -4.44 >-4.30 >-4.30 -4.98 >-4.30 >-4.30 -5.- 06
>-4.30 -4.46 NCI-H460 >-4.00 -4.71 -4.40 >-4.30 >-4.30
-5.11 >-4.30 >-4.- 30 -4.92 >-4.30 -4.92 NCI-H522 -- -4.88
-4.59 >-4.30 >-4.30 -4.34 >-4.30
>-4.30 -4.6- 0 >-4.30 -11.20 Colon Cancer COLO 205 >-4.00
-6.43 -4.87 -6.29 -- <-8.30 -6.99 -5.28 >-4.30 --- -- HCC-2998
>-4.00 -5.39 -4.23 -- -- -- -- -- -4.91 -5.33 -4.77 HCT-116
>-4.00 -- >-4.00 >-4.30 >-4.30 -5.16 -4.40
>-4.30 -- 5.06 >-4.30 -4.82 HCT-15 >-4.00 -4.78 -4.53 -5.61
-5.01 -5.23 -6.70 -5.00 -8.19 -4.96 >- ;-4.00 HT29 >-4.00
-4.67 >-4.00 >-4.30 4.91 >-4.30 >-4.30 >-4.3- 0 -- -- --
KM12 >-4.00 -4.79 -4.47 <-8.30 <-8.30
<-8.30 <-8.30 <-8.- 30 -5.04 >-4.30 -4.36 SW-620 >-4.00
-4.89 >-4.00 -- -- -- -- -- -5.05 >-4.30 >-4.00 CNS Cancer
SF-268 -- -4.63 -4.53 >-4.30 >-4.30 -5.14 >-4.30 >-4.30
-4.80 - >-4.30 -- SF-295 -- -4.80 -4.49 --
<-8.30 -- -- -- -4.77 >-4.30 -- SF-539 -- -4.72 -4.41 >-4.30
-4.50 -4.66 >-4.30 >-4.30 -- -- -- SNB-19 >-4.00 -4.50 -4.34
>-4.30 -- -4.96 >-4.30 >-4.30 >-4- .30 -- >-4.00 SNB-75
>-4.00 -4.55 -4.04 >-4.30 >-4.30
-4.80 >-4.30 >-4.30- -- -- -- U251 >-4.00 -4.47 -4.61
>-4.30 -4.75 -5.22 -7.39 >-4.30 -5.08 >- ;-4.30 -4.32
Melanoma LOX IMVI -- -4.45 -5.47 -- -- -- -- -- <-8.30 <-8.30
-4.65 MALME-3M -4.06 -4.74 -4.50 -6.82 -5.14 <-8.30 -7.46
-6.40 <-8.30 -- - -4.46 M-14 >-4.00 -4.68 >-4.00 >-4.30
>-4.30 -4.91 >-4.30 >-4.- 30 -4.75 >-4.30 -4.62 SK-MEL-2
>-4.00 -4.92 -4.53 >-4.30 >-4.30 >-4.30 >-4.30 >-
;-4.30 >-4.30 >-4.30 -- SK-MEL-28 >-4.00
-4.54 -4.31 >-4.30 >-4.30 -4.63 >-4.30 >-4- .30 -4.73
>-4.30 -- SK-MEL-5 >-4.00 -7.18 -4.64 -- -- -- -- -- -5.28 -6.49
-- UACC-257 >-4.00 -4.71 -4.90 >-4.30 >-4.30 -4.38 >-4.30
>4.3- 0 -4.65 >-4.30 -4.52 UACC-62
>-4.00 -4.74 -4.67 -- -- -- -- -- -5.07 >-4.30 -4.71 Ovarian
Cancer IGROVI >-4.00 -4.68 -4.57 >-4.30 >-4.30 >-4.30 -4.50
>-4.30- >-4.30 >-4.30 -4.19 OVCAR-3 -- -4.92 -4.45 -8.21
<-8.30 <-8.30 -8.07 -- -4.98 >-4.30 -
-4.55 OVCAR-4 -- -4.62 -4.55 -- -- -- -- -- -4.93 >-4.30 -4.19
OVCAR-5 >-4.00 -6.42 -4.33 -6.62 -- <-8.30 -6.95 -6.39 -5.14
>-4.- 30 -4.92 OVCAR-8 >-4.00 -4.69 -4.47 >-4.30 >-4.30
-4.48 >-4.30 >-4.3- 0 >4.30 >-4.30 --
SK-OV-3 -- -4.53 -4.15 >-4.30 -- -4.92 >-4.30 >-4.30 -4.72
>-4- .30 -- Renal Cancer 786-0 >-4.00 -4.83 -4.36 >-4.30
>4.30 -5.08 >-4.30 >-4.30 -- 4.94 >-4.30 >-4.00 A498
>-4.00 -5.00 -4.51 -- -- -- -- -- -5.31 >-4.30
-- ACHN >-4.00 -4.76 <-8.00 -- -4.74 -- -- -- -6.57 -6.61 -4.90
CAKI-1 -- -4.84 -4.54 >-5.99 -- -6.71 -6.91 -6.40 -5.11 -6.30 -4.04
RXF 393 >-4.00 -4.41 -4.53 -6.77 -4.45 -5.99 -7.60 <-8.30 -4.69
>- -4.30 >-4.00 SN12C >-4.00
-4.84 -4.72 -- -- -- -- -- -5.29 -6.02 -4.29 TK-10 >-4.00 -4.81
-4.49 -4.52 -4.60 -5.40 -5.86 -5.22 -5.34 -- -- UO-31 >-4.00 -5.77
-4.68 >-4.30 >-4.30 >-4.30 >-4.30 >-4- .30 -5.10 -4.49
-- Prostate Cancer PC-3 -4.00 -4.89 -4.49
>-4.30 >-4.30 -5.23 -5.75 -4.92 -5.11 >-4.- 30 >-4.00
DU-145 -- -4.72 -4.48 -- -- -- -- -- -5.00 >-4.30 >-4.00 Breast
Cancer MCF7 >-4.00 -4.67 -4.88 >-4.30 >-4.30 -5.13 >-4.30
>-4.30 -- 5.03 >-4.30 -4.05 NCI/ADR-RES --
-6.41 >4.00 >-4.30 >-4.30 -5.09 >-4.30 >-4.3- 0 -5.18
>-4.30 >-4.00 MDA- >-4.00 -4.33 -4.57 -6.35 -- <-8.30 -- --
-6.32 -7.94 -4.84 MB231/ATCC HS 578T >-4.00 >-4.00 -4.08
>-4.30 >-4.30 -4.53 >-4.31 >- -4.30
-5.00 >-4.30 -- MDA-MB-435 -- -4.78 -4.54 >-4.30 >-4.30 -5.17
>-4.30 >-4.30 -4- .94 >-4.30 -- MDA-N >-4.00 -4.90 -- -- --
-- -- -- -- -- -- BT-549 >-4.00 -4.73 -4.81 -7.39 -- -5.54 -5.32
>-4.30 -5.07 >-4.3- 0 -6.32 T-47D
>-4.00 -4.73 -4.48 -4.77 -- -- >-4.30 >-4.30 -5.36 >-4.3- 0
-4.05 MG MID -- -4.87 -4.50 -5.04 -4.72 -5.51 -5.12 -4.81 -5.15 -4.66
-- Delta -4.00 2.31 3.50 3.26 3.58 2.79 3.18 3.49 3.15 3.64 -4.54 Range
0.06 3.18 4.00 4.00 4.00 4.00 4.00 4.00
4.00 4.00 7.20
TABLE-US-00005 TABLE V Log.sub.10LC.sub.50 Panel/Cell Artem-
Trioxane Dimers Pacli- Line isinin 4 5 8a 9 10c 11b 12b 13 14 taxel
Leukemia CCRF-CEM -- >-4.00 >-4.00 >-4.30 >-4.30 >-4.30
>-4.30 &g- t;-4.30 >-4.30 >-4.30
>-4.00 HL-60(TB) >-4.00 -4.13 >-4.00 >-4.30 >-4.30
>-4.30 -4.55 &g- t;-4.30 -- >-4.30 >-4.53 K-562 >-4.00
>-4.00 >-4.00 >-4.30 >-4.30 >-4.30 >-4.3- 0 >-4.30
-- >-4.30 >-4.00 MOLT-4 >-4.00 >-4.00
>-4.00 >-4.30 >-4.30 >-4.30 >-4.- 30 >-4.30 -- --
>-4.00 RPMI-8226 >-4.00 >-4.00 >-4.00 >-4.30 >-4.30
>-4.30 -- -- - >-4.30 >-4.30 >-4.00 SR >-4.00 >-4.00
-- -- -- -- -- -- -- >-4.30 >-4.00
Non-Small Cell Lung Cancer A549/ATCC >-4.00 -4.11 -4.11 >-4.30
>-4.30 >-4.30 >-4.30 &g- t;-4.30 >-4.30 >-4.30 --
EKVX >-4.00 -4.36 -- >-4.30 -- >-4.30 >-4.30 >-4.30
-4.59 &- gt;-4.30 -- HOP-62 >-4.00 -4.20 >-4.00
>-4.30 >-4.30 -4.62 >-4.30 >-- 4.30 -4.54 >-4.30 -4.10
HOP-92 >-4.00 -4.22 -4.05 >-4.30 >-4.30 -4.52 >-4.30
>-4.30- -4.74 >-4.30 -- NCI-H226 >-4.00 >-4.00 -4.11
>-4.30 -- -4.82 -- -- -- -- -- NCI-H23 >-4.00
-4.49 >-4.00 >-4.30 >-4.30 -4.77 >-4.30 >- -4.30 -4.62
>-4.30 -- NCI-H322M -- -4.29 -4.16 >-4.30 >-4.30 -4.57
>-4.30 >-4.30 -4.- 59 >-4.30 >-4.00 NCI-H460 >-4.00
-4.19 >-4.00 >-4.30 >-4.30 -4.62 >-4.30
>- ;-4.30 -4.36 >-4.30 >-4.00 NCI-H-522 -- -4.40 -4.17
>-4.30 >-4.30 >-4.30 >-4.30 <-4.30- >-4.30 >-4.30
>-4.00 Colon Cancer COLO 205 >-4.00 -4.50 -4.15 4.78 -- -5.55
-5.28 >-4.30 >-4.30 >- ;-4.30 >-4.41
HCC-2998 >-4.00 -4.59 >-4.00 -- -- -- -- -- -4.55 >-4.30 -4.26
HCT-116 >-4.00 -4.57 >-4.00 >-4.30 >-4.30 -4.72 >-4.30
>- -4.30 >-4.30 >-4.30 >-4.00 HCT-15 >-4.00 -4.06 -4.03
>-4.30 >-4.30 -4.70 >-4.30
>-4.30- -4.81 >-4.30 >-4.00 HT29 >-4.00 >-4.00 >-4.00
>-4.30 >-4.30 >-4.30 >-4.30- >-4.30 -- -- -4.39 KM12
>-4.00 -4.29 >-4.00 -4.60 -4.36 -5.23 -5.95 -5.02 -4.37 >-4.-
30 >-4.00 SW-620 >-4.00 -4.44
>-4.00 -- -- -- -- -- -4.53 >-4.30 >-4.00 CNS Cancer SF-268 --
-4.23 -4.12 >-4.30 >-4.30 -4.59 >-4.30 <-4.30 -4.31 -
>-4.30 -- SF-295 -- -4.39 -4.04 -- -4.60 -- -- -- -4.33 >-4.30 --
SF-539 -4.34 >-4.00 >-4.30 >-4.30
>-4.30 >-4.30 >-4.30 - -4.56 >-4.30 >-4.00 SNB-19
>-4.00 -4.13 >-4.00 >-4.30 -- -4.44 >-4.30 >-4.30
&g- t;-4.30 -- >-4.00 SNB-75 >-4.00 -4.12 >-4.00 >-4.30
>-4.30 -4.32 >-4.30 >-- 4.30 -- -- -- U251
>-4.00 >-4.00 -4.08 >-4.30 >-4.30 -4.72 >-4.30 -- -4.6-
9 >-4.30 -4.15 Melanoma LOX IMVI -- >-4.00 -4.44 -- -- -- -- --
-5.78 -4.39 >-4.15 MALME-3M >-4.00 -4.28 -4.11 >-4.30
>-4.30 -4.80 >-4.30 >-4.- 30 -4.66
>-4.30 -4.11 M14 >-4.00 -4.14 >-4.00 >-4.30 >-4.30 -4.42
>-4.30 >-4.3- 0 >-4.30 >-4.30 -4.13 SK-MEL2 >-4.00 -4.46
-4.12 >-4.30 >-4.30 >-4.30 >-4.30 >- -4.30 >-4.30
>-4.30 >-4.00 SK-MEL-28 >-4.00
-4.12 >-4.00 >-4.30 >-4.30 >-4.30 >-4.3- 0 >-4.30
-4.34 >-4.30 -- SK-MEL-5 >4.00 -4.53 -4.21 -- -- -- -- -- -4.73
>-4.30 -- UACC-257 >-4.00 -4.30 -4.36 >-4.30 >-4.30
>-4.30 >-4.30 >- ;-4.30 >-4.30 >-4.30
-4.03 UACC-62 >-4.00 -4.29 -4.24 -- -- -- -- -- -4.66 >-4.30
-4.19 Ovarian Cancer IGROVI >-4.00 -4.32 -4.17 >-4.30 >-4.30
>-4.30 >-4.30 >-- 4.30 >-4.30 >-4.30 >-4.00 OVCAR-3
-- -4.42 >-4.00 >-4.30 >-4.30 -5.01
>-4.30 >-4.30 -- 4.51 >-4.30 >-4.00 OVCAR-4 -- -4.16 -4.12
-- -- -- -- -- -4.42 >-4.30 >-4.00 OVCAR-5 >-4.00 -4.54
>-4.00 >-4.30 >-4.30 -4.88 >-4.30 >- -4.30 -4.66
>-4.30 >-4.00 OVCAR-8 >-4.00 -4.03 >-4.00
>-4.30 >-4.30 >-4.30 >-4.30 - >-4.30 >-4.30 >-4.30
>-4.00 SK-OV-3 -- -4.21 >-4.00 >-4.30 -- -4.47 >-4.30
>-4.30 -4.31 &g- t;-4.30 -- Renal Cancer 786-0 >-4.00 -4.31
>-4.00 >-4.30 >-4.30 -4.64 >-4.30
>-4- .30 -4.43 >-4.30 >-4.00 A498 >-4.00 -4.50 -4.21 -- --
-- -- -- -4.74 >-4.30 -4.13 ACHN >-4.00 -4.30 4.47 -- >-4.30
-- -- -- -4.79 >-4.30 -4.45 CAKI-1 -- -4.38 -4.13 >-4.30
>-4.30 -4.93 -4.44 -4.47 -4.66 >-4.3- 0
>-4.00 RXF 393 >-4.00 -4.01 -4.18 >-4.30 >-4.30 -4.73
>-4.30 >-4.3- 0 >-4.30 >-4.30 >-4.00 SN12C >-4.00
-4.35 -4.26 -- -- -- -- -- -4.72 >-4.30 >-4.00 TK-10 >-4.00
-4.38 -4.06 >-4.30 >-4.30 -4.62 >-4.30
>-4.30 - -4.53 >-4.30 -- UO-31 >-4.00 -5.14 -4.26 >-4.30
>-4.30 >-4.30 >-4.30 >-4- .30 >-4.30 >-4.30 --
Prostate Cancer PC-3 >-4.00 -4.34 >-4.00 >-4.30 >-4.30
-4.62 >-4.30 >-4.- 30 -4.63 >-4.30 >-4.00
DU-145 -- -4.36 -4.13 -- -- -- -- -- -4.6- >-4.30 >-4.00 Breast
Cancer MCF7 >-4.00 -4.03 -4.22 >-4.30 >-4.30 >-4.30
>-4.30 >-4.- 30 -4.44 >-4.30 >-4.00 NCI/ADR-RES -- -4.52
>-4.00 >-4.30 >-4.30 -4.63 >-4.30
>-4.- 30 -4.65 >-4.30 >-4.00 MDA- >-4.00 >-4.00 -4.15
>-4.30 -- -5.02 -- -- -4.77 >-4.30 -4- .29 MB231/ATCC HS 578T
>-4.00 >-4.00 >-4.00 >-4.30 >-4.30 >-4.30 >-4- .30
>-4.30 -4.35 >-4.30 -- MDA-MB-435 --
-4.30 -4.09 >-4.30 >-4.30 -4.60 >-4.30 >-4.30 -4- .46
>-4.30 -- MDA-N >-4.00 -4.45 -- -- -- -- -- -- -- -- -- BT-549
>-4.00 -4.31 -4.30 >-4.30 -- -4.61 >-4.30 >-4.30 -4.61 -
>-4.30 >-4.00 T-47D >-4.00 -4.17
>-4.00 >-4.30 -- >-4.30 >-4.30 >-4.30- >-4.30
>-4.30 >-4.00 MG MID -- -4.26 -4.09 -4.32 -4.31 -4.55 -4.37 -4.32
-4.51 -4.30 -- Delta -4.00 0.88 0.37 0.46 0.29 1.00 1.58 0.70 1.27 0.08
-4.06 Range 0.00 1.14 0.47 0.48 0.30 1.25 1.65
0.72 1.49 0.09 .045
The data indicate that alcohol and diol dimers 4 and 5 are
selectively and strongly inhibitory to leukemia cell line RPM 1-8226,
to melanoma cell line SK-MEL-5, and to renal cancer cell line ACHN. The
epoxide dimer 6 and the ketone dimer 7 are
less inhibitory. The data further indicate that the carboxylic acid
derivatives 8a, 9, 10c, 11b, and 12b are also selectively and strong
inhibitory to colon cancer KM12, ovarian cancer OVCAR 3, and to breast
cancer MDA-MB-435. The data lastly indicate
that the acetic acid derivative 12b is highly selective and especially
inhibitory.
The dimers 4, 5, 8a, 9, 10c, 11b and 12b of the present
invention in most instances are as potent and in some instances more
potent than paclitaxel. The data in Tables III, IV and V are
graphically represented in FIGS. 7a, 7b, 7c, 7d, 7e, 7f,
7g, 7h, 7i, 7j and 7k through FIGS. 15j. Dose response curves, shown in
the above mentioned Figures, are obtained by exposing various cancer
cell lines to compounds having a known concentration ([log.sub.10M]),
as discussed in detail above, and then
plotting the percentage growth of each cell line for each
concentration. The drug concentration limits that are tested are
between 10.sup.-4 or -4.00M and 10.sup.-9 or -9.00M. The -4.00M value
being the high concentration and the -9.00M value being the
low concentration. Percentage growth is determined by dividing the
number or mass of cells in the test well by the number or mass of cells
in a control well. Referring to the leukemia cell line MOLT-4 in FIGS.
7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j and
7k the first comparison that is made between artemisinin, paclitaxel,
and the dimers 4, 5, 8a, 9, 10c, 11b, and 12b of the present invention
are the drug concentrations which are necessary to inhibit growth,
graphically represented in FIGS. 7a, 7b, 7c,
7d, 7e, 7f, 7g, 7h, 7i, 7j and 7k as the concentration necessary to
achieve the percentage growth value of +50. As discussed previously,
the five drug dilutions routinely tested range from 10.sup.-4 to
10.sup.-9 molar. Therefore, concentrations less
than or greater than 10.sup.-9 and 10.sup.-4 molar, respectively, that
are required to achieve a desired result are not determined. Referring
now to FIG. 7a, some concentration of paclitaxel that is less than
10.sup.-8M is necessary to achieve primary
growth inhibition; in fact the lower concentrations have been
determined for this drug and the concentration at which primary growth
inhibition occurs using paclitaxel is at 10.sup.-11 molar. FIG. 7b
indicates that some concentration of artemisinin that
is greater than 10.sup.-4 molar is necessary to achieve primary growth
inhibition. Referring to the alcohol and diol trioxane dimers 4 and 5,
dose response curves in FIGS. 7c and 7d, respectively, the leukemia
cell line MOLT-4 displays primary growth
inhibition at drug concentrations that are less than 10.sup.-7 and less
than 10.sup.-8 molar, respectively. Referring to the carboxylic acid
derivatives 8a, 9, 10c, 11b and 12b, dose response curves in FIGS. 7e,
7f, 7g, 7h and 7i, respectively, the
leukemia cell line MOLT-4 displays primary growth inhibition at drug
concentrations that are less than 10.sup.-8, 10.sup.-5, 10.sup.-8 and
10.sup.-7 molar respectively. The drug concentration at which
artemisinin is considered cytostatic, i.e.,
percentage growth is equal to 0, is at a concentration greater than
10.sup.-4 molar. The dimers 4, 5, 8a, 9, 10c, 11b, and 12b reach
cytostasis at some concentration greater than 10.sup.-4 M, while the
paclitaxel concentration necessary to achieve
cytostasis is also some value greater than 10.sup.-4 M. Cytotoxicity,
i.e., the concentration for which the percentage growth is equal to
-50, occurs at a concentration greater than 10.sup.-4 M for paclitaxel,
artemisinin, for both alcohol and diol
trioxane dimers 4 and 5, and for carboxylic acid dimers 8a, 9, 10c, 11
and 12b, respectively.
The potency of the dimers 4, 5, 8a, 9, 10c, 11b, and 12b,
respectively, of the present invention as compared to artemisinin and
paclitaxel varies from cell line to cell line. The mean values for each
drug are presented at the end Tables III, IV
and V and the dimers 4, 5, 8a, 9, 10c, 11b, and 12b of the present
invention are more potent than artemisinin and equivalent to and in
many instances higher in potency than paclitaxel.
The dihydroartemisinin dimer disclosed by M. Cao, et al., and
tested by D. L. Klayman and H. J. Woerdenbag, discussed previously, was
approximately twenty-two times more potent at causing 50% growth
inhibition in one cancer cell line than
artemisinin. With respect to the drug concentrations causing 50% growth
inhibition, the dimers 4, 5, 8a, 9, 10c, 11b, and 12b were at least 100
times more potent than artemisinin. When interpreting the mean values,
it is important to take into
consideration that drug concentrations less than 10.sup.-9M and greater
then 10M were not collected, and this factor is reflected in the range.
For a further comparison on the effects of the trioxane dimers
of the present invention on various cancer cell lines versus the
effects of artemisinin and paclitaxel on the same cell lines see FIGS.
8a, b, c, d, e, f, g, h, i, j and k for
non-small cell lung cancer cell lines, FIGS. 9a, b, c, d, e, f, g, h,
i, j and k for colon cancer cell lines, FIGS. 10a, b, c, d, e, f, g, h,
l, j and k for CNS cancer cell lines, FIGS. 11a, b, c, d, e, f, g, h,
i, j and k for melanoma cancer cell lines,
FIGS. 12a, b, c, d, e, f, g, h, i, j and k for ovarian cancer cell
lines, FIGS. 13a, b, c, d, e, f, g, h, i, j and k for renal cancer cell
lines, FIGS. 14a, b, c, d, e, f, g, h, i, and j for prostate cancer
cell lines and FIGS. 15a, b, c, d, e, f, g, h,
i, and j for breast cancer cell lines.
Acute Toxicity Study of Three
Anti-Malarial Compounds in Male CD-1 Mice
The purpose of this study was to determine the relative
toxicity of four structurally similar anti-malarial compounds (13, 16,
19, and sodium artesunate) following a single intraperitoneal (ip)
injection. This study was not performed in
compliance with the U.S. FDA "Good Laboratory Practice for Nonclinical
Laboratory Studies" (GLP) as described in 21 CFR Part 58; however,
documentation of all procedures and quality control checking of data
was performed as for GLP studies.
Materials and Methods
A. Test Article and Dose Preparation
Compounds 13, 16, 19 and sodium artesunate (Mepha Ltd., Lot No.
1), were provided by NIAID via McKesson BioServices HBOC (Rockville,
Md.). Each compound was dissolved in DMSO (Mallinkrodt Lot No. V18H15)
to achieve a concentration of 200 mg/ml,
and then 3 parts sesame oil (Spectrum Lot No. M10656) was added to make
a working concentration of 50 mg/ml for dose administration. Stability,
strength, and uniformity of the test articles in the dose formulations
were not determined for this study.
B. Test System
Forty-two CD1 male mice purchased from Charles River
Laboratories (Wilmington, Mass.) were used in the study. Mice were
quarantined for 3 days prior to initiation of the study. General
procedures for animal care and housing were in accordance
with the National Research Council (NRC) Guide for the Care and Use of
Laboratory Animals (1996) and the animal welfare standards incorporated
in 9 CFR Part 3, 1991. Mice were approximately 6 weeks old and weighed
25.2-31.2 g at study initiation. They
were individually housed under a 12 hr light-dark cycle, with a
temperature range of 68-72.degree. F. and 33-67% humidity. Purina
Certified Rodent Chow #5002 and purified tap water were available ad
libitum.
C. Experimental Design and Data
Collection
Mice were weighed and randomized into treatment groups on the
day prior to the first dose administration. Due to limitations in the
amount of available test materials, fewer mice in 1000 mg/kg groups
were treated than specified in the protocol. The numbers of animals
intended to be used and actually used with each compound at each dose
level are shown in the table below; the only differences are in the
high-dose groups.
Mice were administered either compounds 13, 16,19 or sodium
artesunate once ip at does levels at 125, 250, 500, or 1000 mg/kg.
Control animals were administered a vehicle solution (25% DMSO and 75%
sesame oil) at a volume of 20 ml/kg. Surviving
animals were sacrificed on Day 8 and blood was collected for clinical
pathology evaluations.
Clinical signs were observed daily, including evaluation of
the injection site 1 to 2 hr. after treatment on Day 1 and once daily
on Days 2-8. Mortality and morbidity were checked twice daily on
weekdays and once daily on the weekend, see Table
VI. Animals were weighed daily and prior to necropsy.
TABLE-US-00006 TABLE VI Mortality Data 750 mg/kg 500 mg/kg
250 mg/kg 125 mg/kg Control No death (12.5 and 18.75 ml/kg) Na
Artesunate -- 3/3 dead 1/3 dead No death 13 2/3 dead 3/3 dead No death
No death 16 3/3 dead 3/3 dead No death No death 19
3/3 dead 1/3 dead No death No death
TABLE-US-00007 TABLE VII Efficacy Study Blood Schizontocidal
Activity Route: IV Route: PO Compound ED.sub.50 ED.sub.90 ED.sub.50
ED.sub.90 Na Artesunate 5.0 40.0 6.0 60.0 (2.9-7.5) (23.0-60.0)
(4.0-10.0) (40.0-100.0) 13 0.55 2.0 4.0 9.0
(0.1-0.8) (0.8-3.2) (2.0-7.0) (4.3-17.0) 16 60.0 1000.0 12b 5.2 10.0
6.0 19.0 (4.9-6.0) (6.9-15.0) (2.7-13.0) (8.0-39.0) 19 1.7 4.5 5.5 18.0
(1.1-4.9) (3.0-11.0) (2.9-13.0) (8.0-38.0)
In conclusion, new C-10 non-acetal trioxane dimer 3, easily
prepared on gram scale and thermally stable, can be used to make a
diverse series of 3-carbon atom linked, oxygenated dimers 4-7 without
destroying the critical pharmacophore peroxide
bond. Each of the new trioxane dimers 4, 5, and 7 is 10 times more
antimalarially potent in vitro than the natural trioxane artemisinin
(I), and alcohol and diol dimers 4 and 5 are strongly inhibitory but
not cytotoxic toward several human cancer cell
lines. Moreover, water-soluble trioxane dimers 8a-10c and 12b are
orally active new antimalarials that are more efficacious than
artelinic acid and than sodium artesunate in mice. These semi-synthetic
new chemical entities 4 and 5 and especially 8a-10c
and 12b, therefore, deserve further preclinical evaluation as potential
drug candidates for chemotherapy of malaria and cancer. Dimers 13 and
19 are more efficacious (when administered both orally and i.v.) and
less toxic (when administered
intraperitoneally to mice as a single dose) than clinically-used sodium
artesunate, thereby giving them a better antimalarial therapeutic index
than sodium artesunate.
The invention is further illustrated by the following
non-limited examples. All scientific and technical terms have the
meanings as understood by one with ordinary skill in the art. The
specific examples which follow illustrate the synthesis of
representative compounds of the instant invention and are not to be
construed as limiting the invention in sphere or scope. The methods may
be adapted to variation in order to produce compounds embraced by this
invention but not specifically disclosed. Further, variations of the
methods to produce the same compounds in somewhat different fashion
will be evident to one skilled in the art. The synthetic descriptions
and specific examples that follow are only intended for the purposes of
illustration,
and are not to be construed as limiting in any manner to make compounds
of the present invention by other methods.
EXAMPLES
Unless otherwise noted, reactions were run in oven-dried
glassware under an atmosphere of argon. Diethyl ether (ether) and
tetrahydrofuran (THF) were distilled from sodium benzophenone ketyl
prior to use. Methylene chloride (CH.sub.2Cl.sub.2)
was distilled from calcium hydride prior to use. All other compounds
were purchased from Aldrich Chemical Company and used without further
purification. Analytical thin-layer chromatography (TLC) was conducted
with Silica Gel 60 F254 plates (250
micrometer thickness, Merck). Column chromatography was performed using
flash silica gel (particle size 400-230 mesh). Yields are not
optimized. Purity of final products was judged to be >95% based on
their chromatographic homogeneity. High
performance liquid chromatography (HPLC) was carried out with a Rainin
HPLX system equipped with two 25 mL/min preparative pump heads using a
Rainin Dynamax 10 mm.times.250 mm (semi-preparative) column packed with
60 .ANG. silica gel (8 .mu.m pore size)
as bare silica. Melting points were measured using a Mel-Temp
metal-block apparatus and are uncorrected. Nuclear magnetic resonance
(NMR) spectra were obtained on a Varian XL-400 spectrometer, operating
at 400 MHz for .sup.1H, 162 MHz for .sup.31P 100
MHz for .sup.13C. .sup.1H and .sup.13C chemical shifts are reported in
parts per million (ppm) downfield from tetramethylsilane, .sup.31P
chemical shifts are measured using 85% phosphoric acid as an external
reference. Splitting patterns are described
as singlet(s), doublet(d), triplet(t), quartet(q), quintet (qt), sextet
(st), multiplet (m) and broad (br). Infrared (IR) spectra were obtained
using a Perkin-Elmer 1600 FT-IR spectrometer. Resonances are reported
in wavenumbers (cm.sup.-1). Low and
high resolution mass spectra (LRMS and HRMS) were obtained with
electronic or chemical ionization (El or Cl) either (1) at Johns
Hopkins University on a VG Instruments 70-S Spectrometer run at 70 eV
for El and run with ammonia (NH.sub.3), butane
(C4H.sub.10) or methane (CH.sub.4) as carrier gas for Cl or (2) at Ohio
State University with a 3-Tesla Finnigan FTMS-2000 Fourier Transform
mass spectrometer. Samples were sprayed from a commercial Analytica
electrospray ionization source, and then
focused into the FTMS cell using a home-built set of ion optics. For
ESI analysis, most compounds were sprayed from a micromolar
concentration of the analyte in various solvent mixtures, such as
tetrahydrofuran/CH.sub.3OH, with added NaCl. This process
generated the sodiated molecular ion (usually as the singly-charged
species), denoted as (M+Na).sup.+. But in some cases, acetic acid or
trifluoroacetic acid was used to generate the protonated molecular ion
(M+H)+ instead. Electron impact (El)
ionization was performed with a Kratos MS-25, using 70 eV ionization
conditions. Combustion analyses were conducted by Atlantic Microlab
(Norcross, Ga.). Various methods of purifying the products of the
present invention are known and understood by
those skilled in the art and the purification methods presented in the
Examples is solely listed by way of example and is not intended to
limit the invention.
Example 1
Synthesis of bis-trioxane O-allyl
ether 12a and bis-trioxane O-acetic acid 12b
Synthesis of bis-trioxane O-allyl
ether 12a.
To a solution of bis-trioxane primary alcohol 4 (200 mg, 0.33
mmol) in anhydrous tetrahydrofuran (20 mL) at -78.degree. C. was added
KHMDS (0.5 M sol. in toluene, 2 mL, 1 mmol) in a dropwise manner. The
reaction was stirred at -78.degree. C.
for 30 mins, at which time allyl bromide (0.4 mL, I mmol) and
18-crown-6 (catalytic) were added. The reaction was then stirred at
-78.degree. C. for a further 1 hour, at which time TLC analysis showed
complete consumption of starting material. The
reaction was quenched with water (5 mL) and organics were extracted
with methylene chloride (3.times.20 mL), dried (MgSO.sub.4) and
concentrated in vacuo. Column chromatography on silica eluting with
10-12% ethyl acetate/hexanes isolated bis-trioxane
O-allyl ether 12a as a viscous oil (204 mg, 96%). .sup.1H NMR (400 MHz,
CDCl.sub.3) .delta. 5.98-5.88 (m, 1H), 5.32 (s, 2H), 5.28-5.23 (m, 1H),
5.14-5.10 (m, 1H), 4.34-4.28 (m, 1H), 4.24-4.17 (m, 1H), 4.04-3.90 (m,
2H), 3.61-3.54 (m, 2H), 2.76-2.60 (m,
2H), 2.38-3.26 (m, 2H), 2.10-1.20 (m), 0.99-0.81 (m, 14H); .sup.13C NMR
(100 MHz, CDCl.sub.3) .delta. 135.4, 116.1, 103.1, 102.9, 88.9, 88.4,
81.1, 74.7, 72.7, 71.7, 71.5, 52.4, 52.2, 44.6, 44.4, 37.3, 36.5, 35.6,
34.5, 34.4, 30.5, 30.4, 29.9, 29.6,
26.1, 26.0, 24.9, 24.6, 24.5, 20.2, 20.1, 13.3, 13.0.
Synthesis of bis-trioxane O-acetic
acid 12.
To a solution of bis-trioxane O-allyl ether 12a (115 mg, 0.178
mmol) in ethyl acetate (3.0 mL), acetonitrile (3.0 mL) and water (1.0
mL) was added ruthenium (III) chloride hydrate (7.4 mg, 0.036 mmol) and
sodium periodate (266 mg, 1.25 mmol) (on
addition of ruthenium chloride the solution turned black). The reaction
was stirred at room temperature for 30 mins (the color of the solution
turned to pale orange) before the reaction mixture was poured into a
mixture of ethyl acetate (30 mL) and
saturated aqueous NH.sub.4Cl solution (20 mL). Organics were extracted
with ethyl acetate (2.times.30 mL), filtered through a pad of celite,
dried (MgSO.sub.4) and concentrated in vacuo. Flash column
chromatography (1% acetic acid in 40% ethyl
acetate/hexane) isolated bis-trioxane O-acetic acid 12b as a white
solid (52.0 mg, 0.078 mmol, 44%). Mp=86-90.degree. C.; .sup.1H NMR (400
MHz, CDCl.sub.3) .delta. 5.33 (s, 2H), 4.46-4.39 (m, 1H), 4.38-4.33 (m,
1H), 4.15 (d, 1H, J=16.4), 4.03 (d, 1H,
J=16.4), 3.86 (dd, 1H, J=8.8, J=5.2), 3.57 (dd, 1H, J=8.8, J =4.4),
2.71-2.52 (m, 2H), 2.37-2.29 (m, 2H), 2.08-1.18 (m, 30H, including two
singlets at 1.39 and 1.38), 0.98-0.85 (m, 2H), 0.94 (apparent doublet,
6H, J=6.0), 0.86 (d, 3H, J=7.2), 0.85 (d,
3H, J=7.2); .sup.13C NMR (100 MHz, CDCl.sub.3) .delta. 171.7, 103.4,
103.1, 89.4, 89.2, 81.1, 81.0, 74.3, 73.6, 71.5, 69.1, 52.2, 52.1,
44.3, 44.1, 37.5, 36.5, 36.0, 34.4, 30.7, 30.7, 30.6, 26.0, 25.9, 24.8,
24.7, 20.2, 20.1,12.9, 12.8; IR (film,
cm.sup.-1) 3506 (br), 2939, 2875, 1759, 1739, 1451, 1377, 1279, 1251,
1206, 1187, 1125, 1052, 1011, 929, 910, 826, 731; HRMS(ES) m/z calcd
for C.sub.36H.sub.56O.sub.11Na (M+Na) 687.3715, found 687.3695.
Example 2
Synthesis of
.alpha.-dihydroartemisinin acetate 2
To a solution of artemisinin 1 (565 mg, 2.00 mmol) in anhydrous
methylene chloride (15.0 mL) at -78.degree. C. was added DIBAL (1.0 M
in toluene, 2.4 mL, 2.4 mmol) in a dropwise manner. The reaction was
stirred at -78.degree. C. for one hour,
at which time TLC analysis confirmed complete consumption of starting
material. Pyridine (0.50 mL, 6.18 mmol), 4-(dimethylamino)-pyridine
(292 mg, 2.4 mmol) and finally acetic anhydride (0.760 mL, 8.05 mmol)
were addded and the reaction was stirred
vigorously at -78.degree. C. for 3 hours before being allowed to warm
to room temperature and stir overnight. The reaction was then quenched
with saturated NH.sub.4Cl solution (20 mL) and organics were extracted
with methylene chloride (3.times.20 mL),
washed with brine, dried (MgSO.sub.4) and concentrated in vacuo. Flash
column chromatography on silica eluting with 14% ethyl acetate/hexanes
isolated .alpha.-dihydroartemisinin acetate 2 as a white solid (600 mg,
1.84 mmol, 92%) with the following
characteristic peaks: .sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 5.78
(d, 1H, J=9.6), 5.44 (s, 1H), 2.60-2.51 (m, 1H), 2.41-2.33 (m, 1H),
2.12 (s, 3H), 1.43 (s, 3H), 0.96 (d, 3H, J=6.0), 0.84 (d, 3H, J=7.2).
Example 3
Synthesis of trioxane isobutene dimer
3
A solution of dihydroartemisinin acetate 2 (DHA acetate) (872
mg, 2.67 mmol) and the allylic bis-silane linker (267 mg, 1.34 mmol) in
methylene chloride (50 mL) was cooled to -78.degree. C. Tin
tetrachloride (1M solution in CH.sub.2Cl.sub.2,
2.67 ml, 2.67 mmol) was further diluted with CH.sub.2Cl.sub.2 (3 mL)
and was added to the reaction mixture dropwise using a syringe pump at
the rate of 6 ml/hour. The reaction was stirred at -78.degree. C. for a
further 45 minutes at which time TLC
analysis confirmed complete consumption of starting material. Saturated
ammonium chloride solution (10 mL) was then added and the reaction was
allowed to warm to room temperature naturally. Organics were extracted
with methylene chloride (3.times.20
mL), dried (Na.sub.2SO.sub.4) and concentrated in vacuo. Gradient
column chromatography on silica eluting with 5%, 7%, 8% and finally 10%
ethyl acetate/hexanes isolated trioxane isobutene dimer 3 as a white
solid (564 mg, 0.96 mmol, 71%). Mp=132-133.degree. C.; .sup.1H NMR (400
MHz, CDCl.sub.3) .delta. 5.41 (s, 2H), 4.87 (s, 2H), 4.30 (ddd, 2H,
J=10.4, J=5.6, J=4.0), 2.75-2.67 (m, 2H), 2.61-2.54 (m, 2H), 2.37-2.23
(m, 4H), 2.04-1.98 (m, 2H), 1.91-1.84 (m, 2H), 1.81-1.75 (m, 2H),
1.67-1.56 (m, 4H), 1.52-1.32 (m, 6H), 1.39 (s, 6H), 1.23-1.20 (m, 2H),
0.94 (d, 6H, J=6.0), 0.90 (d, 6H, J=7.6), 0.98-0.86 (m, 2H); .sup.13C
NMR (100 MHz, CDCl.sub.3) .delta. 147.4, 113.1, 103.1, 88.6, 81.2,
75.5, 52.4, 44.5, 37.1, 36.7, 35.2, 34.5,
30.6, 26.2, 24.7, 24.6, 20.2, 13.3; IR (film, cm.sup.-1) 3060, 2938,
2875, 1641, 1451, 1375, 1121, 1092, 1054, 1007, 878, 732; HRMS(ES) m/z
calcd for C.sub.34H.sub.52O.sub.8Na (M+Na) 611.3560, found 611.3555;
Anal (C.sub.34H.sub.52O.sub.8) C, H.
Example 4
Synthesis of bis-trioxane primary
alcohol 4
A solution of trioxane isobutene dimer 3 (0.89 g, 1.51 mmol) in
anhydrous tetrahydrofuran (25 mL) was cooled to 0.degree. C.
Borane-dimethyl sulfide complex (BH.sub.3DMS) (2.0 M solution in
diethyl ether, 0.9 mL, 1.80 mmol) was carefully added
and the reaction was allowed to warm to room temperature and stir for 3
hours. At this time TLC analysis confirmed that no starting material
remained. A suspension of sodium perborate4H.sub.2O
(NaBO.sub.34H.sub.2O) (1.17 g, 7.60 mmol) in water (12 mL)
was slowly added and the resulting suspension was allowed to stir for
17 hours. Water (10 mL) and methylene chloride (50 mL) were added and
organics were extracted with methylene chloride (3.times.20 mL), dried
(Na.sub.2SO.sub.4) and concentrated in
vacuo to give a white solid. Gradient column chromatography on silica
eluting with 20%, 30% and finally 40% ethyl acetate/petroleum ether
isolated bis-trioxane primary alcohol 4 as a white solid (0.85 g, 1.40
mmol, 93%). .sup.1H NMR (CDCl.sub.3, 400
MHz) .delta. 6 35 (s, 1H), 5.34 (s, 1H), 4.47-4.40 (m, 1H), 4.33 (qt,
1H, J=6.0), 3.83-3.75 (m, 1H), 3.67-3.60 (m, 1H), 3.17 (dd, 1H, J=7.6,
J=6.1), 2.64 (qt, 1H, J=6.9), 2.59 (qt, 1H, J=6.9), 2.32 (t, br, 2H,
J=14.1), 2.06-1.97 (m, 3H), 1.95-1.87 (m,
2H), 1.86-1.74 (m, 2H), 1.70-1.55 (m, 8H), 1.50-1.30 (m, 14H, including
singlet at 1.40), 0.99-0.90 (m, 2H), 0.95 (d, 6H, J=5.8), 0.87
(apparent t, 6H, J=6.9); .sup.13C NMR (CDCl.sub.3, 100 MHz) .delta.
103.12, 102.97, 89.47, 89.22, 81.11 (2), 73.86,
71.27, 65.12, 52.20, 52.07, 44.18, 44.01, 37.68, 37.46, 37.43, 36.52,
36.51, 34.40, 34.37, 31.26, 30.74 (2), 30.65, 25.95, 25.89, 24.83 (2),
24.73, 24.70, 20.15, 20.10, 12.89, 12.61; HRMS (El, m/z) for
C.sub.34H.sub.54O.sub.9Na requires 629.3660, found
629.3697; IR (film, cm.sup.-1) 3490; Mp. 81-82.degree. C.; Anal
(C.sub.34H.sub.56O.sub.10) C, H.
Example 5
Synthesis of bis-trioxane vicinal diol 5
To a solution of trioxane isobutene dimer 3 (21.0 mg, 0.036
mmol) and 4-methylmorpholine N-oxide (5.0 mg, 0.043 mmol) in acetone
(2.0 mL) was added osmium tetroxide (25 mg/2 mL aqueous solution, 0.016
mL, catalytic) and the reaction was stirred
vigorously at room temperature for 24 hrs. The reaction mixture was
then quenched with saturated aqueous NaHSO.sub.3 solution (2.0 mL) and
stirred for an additional 30 mins (during which time the reaction
turned a pale orange color). The reaction
mixture was poured into a mixture of diethyl ether (20 mL) and
saturated aqueous NH.sub.4Cl solution (20 mL) and organics were
extracted with ethyl acetate (2.times.30 mL), washed with brine, dried
(MgSO.sub.4) and concentrated in vacuo. Flash column
chromatography on silica eluting with 50% ethyl acetate/hexanes)
isolated bis-trioxane vicinal diol 5 as a white solid (20.3 mg, 0.033
mmol, 92%). Mp=159-160.degree. C.; .sup.1H NMR (400 MHz, CDCl.sub.3)
.delta. 5.36 (s, 1H), 5.35 (s, 1H), 4.74-4.70
(m, 1H), 4.56-4.51 (m, 1H), 4.09 (s, 1H), 3.71-3.62 (m, 2H), 3.12 (t,
1H, J=7.2), 2.64-2.52 (m, 2H), 2.36-2.26 (m, 2H), 2.04-1.99 (m, 2H),
1.96-1.63 (m, 12H), 1.46-1.20 (m, 14H, including two singlets at 1.40
and 1.39), 0.96 (d, 3H, J=6.0), 0.95 (d, 3H,
J=6.0), 0.89 (d, 3H, J=7.6), 0.88 (d, 3H, J=7.6), 0.98-0.86 (m, 2H);
.sup.13C NMR (100 MHz, CDCl.sub.3) .delta. 103.0, 102.9, 89.7, 89.5,
81.1, 81.0, 74.7, 70.6, 70.5, 68.4, 52.0, 43.8, 43.7, 37.8, 37.5, 36.5,
34.9, 34.3, 31.0, 30.9, 25.9, 25.9, 24.9,
24.8, 24.8, 20.1, 12.5, 12.4; IR (film, cm.sup.-1) 3499, 2951, 2876,
1453, 1378, 1207, 1108, 1054, 1009, 912, 878, 844, 732; HRMS(ES) m/z
calcd for C.sub.34H.sub.54O.sub.10Na (M+Na) 645.3609, found 645.3559.
Example 6
Synthesis of bis-trioxane epoxide 6
To a solution of trioxane isobutene dimer 3 (34.1 mg, 0.058
mmol) in anhydrous methylene chloride (10.0 mL) at -78.degree. C. was
rapidly added dimethyl dioxirane (DMDO) (0.08 M solution in acetone,
3.8 mL, 0.29 mmol). The reaction was stirred
at -78.degree. C. for 30 minutes before being allowed to warm to room
temperature. The reaction was then concentrated in vacuo, giving a
yellow oil. Flash column chromatography on silica eluting with 20%
theyl acetate/hexanes isolated bis-trioxane
epoxide 6 as a white solid (28.1 mg, 0.047 mmol, 80%).
Mp=147-148.degree. C.; .sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 5.48
(s, H), 5.43 (s, H), 4.45 (dd, 1H, J=10.0, J=6.0), 4.22 (dd, 1H,
J=10.0, J=6.0), 2.82-2.72 (m, 2H), 2.68-2.62 (m, 3H),
2.43-2.33 (m, 3H), 2.02-1.97 (m, 2H), 1.88-1.82 (m, 2H), 1.75-1.70 (m,
2H), 1.62-1.58 (m, 2H), 1.54-1.26 (m, 11H), 1.39 (s, 6H), 0.98-0.88 (m,
3H), 0.93 (d, 6H, J=6.4), 0.92 (d, 6H, J=6.4), 0.80 (d, 6H, J=7.6);
.sup.13C NMR (100 MHz, CDCl.sub.3) .delta. 103.43, 103.40, 87.94,
87.93, 81.10, 81.07, 75.44, 74.37, 60.43, 54.46, 52.54, 52.50, 44.58,
36.91, 36.70, 34.40, 33.50, 33.01, 30.40, 30.36, 26.18, 24.45, 24.35,
24.32, 20.22, 20.19, 13.69, 13.51; IR (film, cm.sup.-1) 2939, 2875,
1452, 1376, 1280, 1208,
1188, 1123, 1091, 1057, 1006, 941, 878, 754; HRMS(ES) m/z calcd for
C.sub.34H.sub.52O.sub.9Na (M+Na) 627.3509, found 627.3478.
Example 7
Synthesis of bis-trioxane ketone 7
To a solution of trioxane isobutene dimer 3 (30 mg, 0.051 mmol)
in anhydrous N,N-dimethylformamide (25 .mu.L) was added OSO.sub.4 (2.5%
weight % in t-BuOH, 0.1 mol %). The reaction mixture was stirred for 5
minutes before Oxone.RTM. (63 mg, 0.2
mmol) was added in one portion. The reaction was then stirred for a
further 2 hours, at which time TLC analysis confirmed full consumption
of starting material. The reaction was quenched with saturated
Na.sub.2SO.sub.3 solution (10 mL) and water (10
mL) and stirred for 1 hour before organics were extracted with
methylene chloride (3.times.20 mL), dried (Na.sub.2SO.sub.4) and
concentrated in vacuo. Flash column chromatography on silica eluting
with 25% ethyl acetate/hexanes) isolated bis-trioxane
ketone 7 as a white solid (21 mg, 0.035 mmol, 70%). Mp=120-121.degree.
C.; .sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 5.34 (s, 2H), 4.75 (m,
2H), 2.90 (m, 2H), 2.75 (m, 2H), 2.59 (dd, 2H, J=16, J=4), 2.33 (dt,
2H, J=16, J=9), 2.04-1.96 (m, 2H), 1.94
(m, 2H), 1.79 (m, 2H), 1.68-1.57 (m, 6H), 1.48-1.22 (m, 14H), 0.99 (d,
6H, J=6.4), 0.88 (d, 6H, J=7.2); .sup.13C NMR (100 MHz, CDCl.sub.3)
.delta. 196.8, 103.8, 89.3, 71.6, 52.5, 44.5, 44.3, 37.7, 36.8, 34.7,
30.3, 26.3, 25.0, 24.8, 20.4, 13.8; IR
(film, cm.sup.-1) 1722; HRMS(ES) m/z calcd for
C.sub.33H.sub.50O.sub.9Na (M+Na) 613.3347, found 613.3303.
Example 8
Synthesis of bis-trioxane primary
succinate monoester 8a
To a solution of bis-trioxane primary alcohol 4 (50 mg, 0.082
mmol) and succinic anhydride (24 mg, 0.24 mmol) in methylene chloride
(10 mL) at 0.degree. C. was added 4-(dimethylamino)-pyridine (10 mg,
0.082 mmol). The reaction was allowed to
warm to room temperature and was then stirred for 12 hours, at which
TLC analysis showed complete consumption of starting material. Organics
were extracted with ethyl acetate (3.times.30 mL), washed with brine
(10 mL), dried (MgSO.sub.4) and
concentrated in vacuo. Flash column chromatography on silica eluting
with 50% ethyl acetate/hexanes to isolated bis-trioxane primary
succinate monoester 8a as a white solid (40 mg, 0.068 mmol, 84%).
.sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 5.39 (s,
1H), 5.31 (s, 1H), 4.39-4.32 (m, 2H), 4.28-4.18 (m, 3H), 2.74-2.54 (m,
6H), 2.38-2.24 (m, 2H), 2.22-2.12 (m, 1H), 2.06-1.96 (m, 2H), 1.95-1.85
(m, 2H), 1.84-1.60 (m, 11H), 1.48-1.20 (m, 16H), 1.00-0.80 (m, 12H);
.sup.13C NMR (100 MHz, CDCl.sub.3) .delta. 175.4, 172.0, 102.9, 103.6,
89.4, 88.5, 81.1, 74.1, 71.1, 67.1, 52.4, 52.1, 44.6, 44.1, 37.4, 37.3,
36.6, 36.5, 34.4, 34.3, 30.5, 30.4, 30.0, 29.7, 29.4, 29.0, 26.0, 25.9,
24.7, 20.3, 20.1, 13.3, 12.7; HRMS(ES) m/z calcd for
C.sub.38H.sub.58O.sub.12Na
(M+Na) 729.3820, found 729.3795.
Example 9
Synthesis of bis-trioxane primary
alcohol isonicotinate 8b
To a stirring suspension of bis-trioxane primary alcohol 4
(30.4 mg, 0.050 mmol) and isonicotinic acid (20.1 mg, 0.163 mmol) in
anhydrous methylene chloride (1 mL) was added
4-(dimethylamino)-pyridine (23.5 mg, 0.192 mmol) and
1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide (EDC) hydrochloride
(39.2 mg, 0.204 mmol). A further 1.5 mL of anhydrous methylene chloride
was added to wash down the flask walls and the reaction was stirred at
room temperature for 3 hours, at which
time TLC analysis showed full consumption of starting material. Water
(5 mL), saturated NaHCO.sub.3 solution (5 mL) and methylene chloride (5
mL) were added and organics were extracted with methylene chloride
(3.times.20 mL), dried (Na.sub.2SO.sub.4)
and concentrated in vacuo to give a white solid. Gradient column
chromatography on silica (crude was dry-loaded) eluting firstly with
25% ethyl acetate/petroleum ether and then 30% ethyl acetate/petroleum
ether isolated bis-trioxane primary alcohol
isonicotinate 8b as a white solid (32.6 mg, 0.046 mmol, 91%).
Mp=74-78.degree. C.; [.alpha.].sub.D.sup.24.5 77.8 (CHCl.sub.3,
c=0.06); .sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 8.78 (s, br, 2H),
7.86 (s, br, 2H), 5.33 (s, 1H), 5.29 (s, 1H), 4.55 (s,
1H), 4.54 (s, 1H), 4.51-4.44 (m, 1H), 4.37-4.30 (m, 1H), 2.70 (st, 1H,
J=7.0), 2.59 (st, 1H, J=7.0), 2.45-2.36 (m, br, 1H), 2.31 (td, 2H,
J=14.0, J=3.7), 2.05-1.96 (m, 2H), 1.95-1.73 (m, 6H), 1.69-1.50 (m,
6H), 1.41-1.15 (m, 14H, including two singlets
at 1.40 and 1.39), 0.98-0.92 (m, 2H), 0.96 (d, 3H, J=5.9), 0.94 (d, 3H,
J=5.9), 0.88 (d, 3H, J=7.4), 0.87 (d, 3H, J=7.4); .sup.13C NMR (100
MHz, CDCl.sub.3) .delta. 164.99, 150.49 (2), 137.93, 122.91 (2),
103.16, 102.87, 89.52, 88.83, 81.12, 81.11,
73.23, 70.83, 68.10, 52.30, 52.07, 44.32, 44.06, 37.50, 37.47, 36.64,
36.54, 34.42, 34.39, 33.95, 30.61, 30.58, 30.49, 30.15, 26.02, 26.01,
24.97, 24.89, 24.76, 24.67, 20.17, 20.10, 13.08, 12.72; IR (film,
cm.sup.-1) 2942, 1866, 1726, 1452, 1407, 1372,
1321, 1276, 1210, 1123, 1106, 1057, 1046, 1006, 931, 876, 756, 707;
HRMS (El, m/z) calcd for C.sub.40H.sub.57NO.sub.10Na (M+Na) 734.3875,
found 734.3855; Anal (C.sub.40H.sub.57NO.sub.10) C, H.
Example 10
Synthesis of tertiary alcohol primary
succinate ester 9
To a solution of bis-trioxane vicinal diol 5 (52.9 mg, 0.085
mmol) in anhydrous methylene chloride (3.0 mL) was added succinic
anhydride (25.5 mg, 0.255 mmol) and 4-(dimethylamino)-pyridine (10.4
mg, 0.085 mmol). The reaction was stirred for 24
hours at room temperature, at which time TLC analysis confirmed full
consumption of starting material. The reaction mixture was then poured
into a mixture of methylene chloride (30 mL) and saturated NH.sub.4Cl
solution (30 mL). Organics were extracted
with methylene chloride (3.times.20 mL), washed with brine, dried
(MgSO.sub.4) and concentrated in vacuo. Flash column chromatography on
silica eluting with 2-propanol/methylene chloride/ethyl acetate
(1:3:18) isolated tertiary alcohol primary succinate
ester 9 as a white solid (52.0 mg, 0.071 mmol, 85%). Mp=95-97.degree.
C.; .sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 5.38 (s, 1H), 5.34 (s,
1H), 4.61-4.52 (m, 2H), 4.29 (Abq, 2H, J.sub.AB=18.8,
.DELTA..nu..sub.AB=11.6), 2.72-2.66 (m, 4H), 2.58-2.50 (m,
2H), 2.36-2.24 (m, 2H), 2.04-1.58 (m, 13H), 1.46-1.18 (m, 11 H), 1.40
(s, 3H), 1.39 (s, 3H), 0.95 (d, 6H, J=6.0), 0.88 (d, 3H, J =7.6), 0.87
(d, 3H, J=7.6), 0.98-0.86 (m, 2H); .sup.13C NMR (100 MHz, CDCl.sub.3)
6176.4, 171.7, 103.2, 102.9, 89.6, 89.0,
81.1, 81.0, 73.3, 70.6, 70.3, 68.6, 52.1, 51.9, 44.1, 43.7, 37.5, 36.6,
36.5, 36.3, 35.1, 34.4, 34.3, 30.8, 30.7, 29.2, 29.1, 25.9, 25.8, 24.8,
24.7, 20.2, 20.1, 12.8, 12.5; IR (film, cm.sup.-1) 3502, 2950, 2872,
1737, 1713, 1453, 1378, 1208, 1168, 1106,
1054, 1009, 942, 878, 844, 735; HRMS(ES) m/z calcd for
C.sub.38H.sub.58O.sub.13Na (M+Na) 745.3769, found 745.3726;
[.alpha.].sub.D.sup.23.5 56.6 (CHCl.sub.3, c=0.16); Anal
(C.sub.38H.sub.58O.sub.13) C, H.
Example 11
Synthesis of bis-trioxane
.beta.-hydroxysulfide ester 10a
To a solution of bis-trioxane epoxide 6 (80.0 mg, 0.132 mmol)
in anhydrous diethyl ether (10.0 mL) was added methyl
4-mercaptobenzoate (44.4 mg, 0.264 mmol) and neutral aluminum oxide
(1.0 g, type W 200 super I, Woelm Pharma, Germany). The
resulting slurry was stirred at room temperature for 3 hours, at which
time TLC analysis confirmed full consumption of starting material. The
reaction mixture was then filtered through a pad of celite and the
remaining solid was washed with ethyl
acetate (2.times.30 mL) before concentration of the organics in vacuo.
Flash column chromatography on silica eluting with 25% ethyl
acetate/hexanes isolated bis-trioxane p-hydroxysulfide ester 10a as a
sticky solid (81.2 mg, 0.105 mmol, 80%). .sup.1H
NMR (400 MHz, CDCl.sub.3) .delta. 7.67 (ABq, 4H, J.sub.AB=8.4,
.DELTA..nu..sub.AB=154.4), 5.36 (s, 1H), 5.35 (s, 1H), 4.69 (dd, 1H,
J=10.4, J=6.0), 4.69 (dd, 1H, J=10.0, J=6.0), 3.88 (s, 3H), 3.52 (ABq,
2H, J.sub.AB=12.4, .DELTA..nu..sub.AB=44.4),
2.65-2.55 (m, 1H), 2.52-2.42(m, 1H), 2.34-2.24 (m, 2H), 2.08-1.58 (m,
12H), 1.46-1.18 (m, 10H), 1.36 (s, 3H), 1.31 (s, 3H), 0.94 (d, 3H,
J=6.0), 0.85 (d, 3H, J=6.8), 0.84 (d, 3H, J=7.2), 0.98-0.86 (m, 2H).
.sup.13C NMR (100 MHz, CDCl.sub.3)
.delta.166.9, 145.0, 129.6, 127.7, 126.4, 102.9, 102.8, 89.7, 89.3,
81.1, 81.0, 74.9, 70.8, 70.5, 52.1, 51.9, 43.9, 43.6, 42.4, 38.3, 37.4,
36.5, 36.4, 36.1, 34.4, 34.3, 30.8, 30.7, 26.0, 25.9, 24.8, 24.7, 20.1,
20.0, 12.7, 12.4; IR (film, cm.sup.-1)
3498, 2951, 2876, 1721, 1594, 1430, 1377, 1276, 1182, 1110, 1054, 1008,
942, 880, 845, 762, 736.
Example 12
Synthesis of bis-trioxane
P-hydroxysulfone ester 10b
To a solution of bis-trioxane .beta.-hydroxysulfide ester 10a
(40.0 mg, 0.052 mmol) in tetrachloromethane (1.5 mL), acetonitrile (1.5
mL) and H.sub.2O (2.3 mL) was added ruthenium (III) chloride hydrate
(catalytic) and periodic acid (23.7 mg,
0.104 mmol, 2.0) (on addition of ruthenium chloride the solution turned
black). On stirring for 30 minutes at room temperature, diethyl ether
(30 mL) was added and the reaction was stirred for a further 10
minutes. The reaction mixture was then dried
(MgSO.sub.4), filtered through a pad of celite and the remaining solid
was washed with ethyl acetate (30 mL). The organics were then
concentrated in vacuo and flash column chromatography on silica
eltuting with 30% ethyl acetate/hexanes isolated
bis-trioxane .beta.-hydroxysulfone ester 10b as a white solid (32.0 mg,
0.040 mmol, 76%). Mp=115-117.degree. C.; .sup.1H NMR (400 MHz,
CDCl.sub.3) .delta. 8.21 (ABq, 4H, J.sub.AB=8.4,
.DELTA..nu..sub.AB=73.6), 5.70 (s, 1H), 5.36 (s, 1H), 5.19 (dd, 1H,
J=10.8, J=6.0), 4.88 (s, 1H), 4.58 (dd, 1H, J=9.6, J=6.4), 3.95 (s,
3H), 3.81 (ABq, 2H, J.sub.AB=13.6, .DELTA..nu..sub.AB=278.4), 2.90-2.82
(m, 1H), 2.70-2.56 (m, 2H), 2.43-2.30 (m, 2H), 2.20-1.20 (m, 16H), 1.54
(s, 3H), 1.24 (s, 3H), 0.96 (d, 6H, J
=6.0), 0.93 (d, 3H, J=8.0), 0.88 (d, 3H, J=7.6), 0.98-0.86 (m, 2H);
.sup.13C NMR (100 MHz, CDCl.sub.3) .delta. 165.8, 145.3, 134.3, 129.9,
128.5, 103.6, 102.8, 90.1, 88.5, 81.2, 73.6, 71.6, 71.1, 60.1, 52.6,
52.5, 51.8, 45.0, 43.3, 39.5, 37.5, 37.3,
36.5, 34.5, 34.3, 30.5, 30.4, 26.4, 26.0, 25.0, 24.8, 24.6, 24.3, 20.3,
20.0, 13.7, 11.9; IR (film, cm.sup.-1) 3458, 2951, 2875, 1731, 1435,
1377, 1320, 1280, 1153, 1105, 1051, 1015, 911, 880, 733; HRMS(ES)
mlzcalcd for C.sub.42H.sub.60O.sub.13SNa (M+Na)
827.3646, found 827.3661.
Example 13
Synthesis of bis-trioxane
.beta.-hydroxysulfone benzoic acid 10c
A solution of bis-trioxane .beta.-hydroxysulfone ester 10b
(19.7 mg, 0.024 mmol) in 2.5% KOH/MeOH (1.0 mL) was stirred vigorously
at room temperature for three hours, at which time TLC analysis
confirmed complete consumption of starting material. The solution was
then evaporated to dryness in vacuo, before the addition of water (10
mL). This solution was acidified with acetic acid until pH=4.0 was
attained and organics were then extracted with ethyl acetate
(2.times.30 mL), dried (MgSO.sub.4)
and concentrated in vacuo. Flash column chromatography on silica
eluting with 2-propanol/methylene chloride/ethyl acetate (1:3:18)
isolated bis-trioxane .beta.-hydroxysulfone benzoic acid 10c as a white
solid (14.7 mg, 0.019 mmol, 79%). Mp=143-145.degree. C.;
[.alpha.].sub.D.sup.23.9 105.2 (CHCl.sub.3, c=0.07); .sup.1H NMR (400
MHz, CDCl.sub.3) .delta. 8.21 (ABq, 4H, J.sub.AB=8.4,
.DELTA..nu..sub.AB=76.4), 5.71 (s, 1H), 5.38 (s, 1H), 5.19 (dd, 1H,
J=10.8, J=6.4), 4.63 (dd, 1H, J=9.2,
J=6.0 Hz), 3.82 (ABq, 2H, J.sub.AB=13.6, .DELTA..nu..sub.AB=266.4 Hz),
2.85-2.82 (m, 1H), 2.70-2.56 (m, 2H), 2.43-2.30 (m, 2H), 2.20-1.20 (m,
22H, including two singlets at 1.56 and 1.25), 0.96 (d, 6H, J=6.0),
0.93 (d, 3H, J=8.0), 0.88 (d, 3H, J=7.6),
0.98-0.86 (m, 2H); .sup.13C NMR (100 MHz, CDCl.sub.3) .delta. 168.0,
145.7, 133.5, 130.4, 128.5, 103.8, 102.9, 90.1, 88.7, 81.3, 73.7, 71.8,
71.2, 60.2, 52.6, 51.9, 44.9, 43.3, 39.4, 37.5, 37.4, 37.3, 36.5, 34.5,
34.3, 30.6, 30.5, 26.1, 25.9, 25.0,
24.8, 24.5, 24.4, 20.2, 20.0, 13.6, 11.9; IR (film, cm.sup.-1) 3459,
2939, 2875, 1723, 1432, 1403, 1378, 1319, 1300, 1228, 1154, 1099, 1051,
1015, 911, 877, 732, 616; HRMS(ES) m/z calcd for
C.sub.41H.sub.58O.sub.13SNa (M+Na) 813.3490, found 813.3500;
Anal (C.sub.41H.sub.58O.sub.13) C, H.
Example 14
Synthesis of bis-trioxane styryl
tertiary alcohol 11a
A solution of styryllithium was prepared by adding t-BuLi (1.7
M in hexanes, 1.2 ml, 2.04 mmol) to a solution of 4-bromostyrene (0.13
mL, 1 mmol) in anhydrous diethyl ether (5 mL). The resulting deep red
solution was stirred for 30 minutes to
ensure complete formation of styryllithium. To a solution of
bis-trioxane ketone 7 (30 mg, 0.051 mmol) in anhydrous tetrahydrofuran
was added the solution of styryllithium (0.35 ml, .about.0.07 mmol) at
-78.degree. C. and the reaction was stirred for
30 minutes, at which time TLC analysis confirmed full consumption of
starting material. Saturated ammonium chloride solution (5 mL) was
added and organics were extracted with methylene chloride (3.times.20
mL), dried (MgSO.sub.4) and concentrated in
vacuo. Gradient column chromatography on silica eluting with 10 and
then 15% ethyl acetate/petroleum ether isolated bis-trioxane styryl
tertiary alcohol 11a as a viscous oil (26 mg, 0.037 mmol, 74%). .sup.1H
NMR (400 MHz, CDCl.sub.3) .delta. 7.45 (d,
J=8.4, 2H), 7.35 (d, J=8.4, 2H), 6.68 (dd, J=10.9, J=17.6, 1 H), 5.70
(d, J=17.6, 1 H), 5.35 (s, 2H), 5.2 (d, J=10.9, 2H), 4.50-4.40 (m, 1H),
4.25-4.12 (m, 1H), 2.78-2.42 (m, 4H), 2.38-1.60 (m, 14H), 1.48-1.20 (m,
14H), 1.00-0.80 (m, 14H).
Example 15
Synthesis of bis-trioxane tertiary
alcohol benzoic acid 11b
To a solution of bis-trioxane styryl tertiary alcohol 11a (20
mg, 0.028 mmol) in acetone (3 mL) was added KMnO.sub.4 (large excess)
as a solid. The reaction was stirred at room temperature for 6 hours,
at which time TLC analysis confirmed full
consumption of starting material. 2-propanol was added to quench any
excess KMnO.sub.4 and the reaction mixture was concentrated in vacuo.
Ethyl acetate (10 mL) and water (10 mL) were added and organics were
extracted with ethyl acetate (3.times.10
mL), dried (MgSO.sub.4) and concentrated in vacuo. Flash column
chromatography on silica eluting with 90% ethyl acetate/petroleum ether
isolated bis-trioxane tertiary alcohol benzoic acid 11b as a white
solid (19 mg, 0.014 mmol, 50%). .sup.1H NMR (400
MHz, CDCl.sub.3) .delta. 7.80 (d, 2H, J=8.4), 7.39 (d, 2H, J=8.4), 5.36
(s, 2H), 4.40-4.32 (m, 1H), 4.12-4.06 (m,1H), 2.80-2.42 (m, 4H),
2.40-2.10 (m, 3H), 2.10-1.60 (m, 15H), 1.48-1.20 (m, 14H), 1.00-0.80
(m, 14H); .sup.13C NMR (100 MHz, CDCl.sub.3)
.delta. 167.4, 132.5, 130.6, 130.0, 127.7, 104.7, 104.6, 90.5, 89.9,
82.3, 82.1, 78.4, 74.1, 73.6, 54.1, 53.8, 46.4, 45.9, 43.4, 39.8, 38.6,
38.5, 37.8, 37.7, 35.9, 35.8, 32.1, 31.9, 26.4, 26.1, 26.0, 25.9, 25.8,
25.7, 20.8, 20.7, 13.9, 13.6; HRMS(ES)
m/z calcd for C.sub.40H.sub.56O.sub.11Na (M+Na) 735.3715, found
735.3717.
Example 16
Synthesis of bis-trioxane primary
alcohol isonicotinate N-oxide 13
To a stirring suspension of bis-trioxane primary alcohol 4
(0.14 g, 0.24 mmol) and commercially available (Aldrich) isonicotinic
acid N-oxide (0.11 g, 0.76 mmol) in anhydrous methylene chloride (10
mL) was added 4-(dimethylamino)-pyridine (0.11
g, 0.93 mmol) and 1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide
hydrochloride (0.17 g, 0.90 mmol). A further 5 mL of anhydrous
methylene chloride was added to wash down the flask walls and the
reaction was stirred at room temperature for 4 hours, at
which time TLC analysis showed full consumption of starting material.
Water (5 mL), 3M HCl solution (10 mL) and methylene chloride (5 mL)
were added and organics were extracted with methylene chloride
(3.times.30 mL), dried (Na.sub.2SO.sub.4) and
concentrated in vacuo to give a colorless oil (0.23 g). Gradient column
chromatography on silica (crude was dry-loaded) eluting firstly with
70% ethyl acetate/petroleum ether and then with 80% ethyl
acetate/petroleum ether isolated bis-trioxane primary
alcohol isonicotinate N-oxide 13 as a white solid (0.17 g, 0.23 mmol,
98%). .sup.1H NMR (CDCl.sub.3, 400 MHz) .delta. 8.22 (d, 2H, J=7.3),
7.89 (d, 2H, J =7.3), 5.32 (s, 1H), 5.29 (s, 1H), 4.52 (s, 1H), 4.51
(s, 1H), 4.51-4.54 (m, 1H), 4.39-4.32 (m,
1H), 2.67 (st, 1H, J=7.0), 2.57 (st, 1H, J=7.0), 2.42-2.26 (m, 3H),
2.07-1.97 (m, 2H), 1.97-1.85 (m, 2H), 1.84-1.74 (m, 4H), 1.70 -1.47 (m,
6H), 1.41-1.19 (m, 14H, including two singlets at 1.40 and 1.39),
1.00-0.91 (m, 2H), 0.96 (d, 3H, J=5.6), 0.95 (d,
3H, J=5.6), 0.88 (d, 3H, J=6.9), 0.86 (d, 3H, J=6.9); .sup.13C NMR
(CDCl.sub.3, 100 MHz) .delta. 163.27, 139.35 (2), 127.26, 126.39 (2),
103.10, 102.80, 89.64, 89.01, 81.12, 81.09, 72.99, 70.52, 68.37, 52.22,
52.01, 44.21, 43.97, 37.56, 37.49, 36.63,
36.53, 34.40, 34.36, 33.98, 30.95, 30.58, 30.52, 29.68, 26.03, 25.98.
24.92, 24.88, 24.77, 24.75, 20.16, 20.07, 12.96, 12.62; HRMS (El, m/z)
for C.sub.40H.sub.57NO.sub.11Na requires 750.3824, found 750.3845; IR
(film, cm.sup.-1) 2931, 2871, 1719, 1609,
1448, 1373, 1261, 1156, 1108, 1049, 1037, 1008, 925, 732; Mp.
114-122.degree. C.; [.alpha.].sub.D.sup.231 51.7 (CHCl.sub.3, c=0.67);
Anal (C.sub.40H.sub.59NO.sub.12) C, H, N.
Example 17
Synthesis of bis-trioxane diphenyl
phosphate 14
To a stirring solution of bis-trioxane primary alcohol 4 (8.0
mg, 0.013 mmol) in anhydrous methylene chloride (0.5 mL) was added
diphenyl chlorophosphate (10 .mu.L, 0.048 mmol) and pyridine (20 .mu.L,
0.247 mmol). A further 1 mL of anhydrous
methylene chloride was used to wash down the inside walls of the flask
and the reaction was stirred at room temperature. TLC analysis after 18
hours showed a substantial amount of starting material still present. A
second portion of diphenyl
chlorophosphate (50 .mu.L, 0.241 mmol) and 4-(dimethylamino)-pyridine
(15.0 mg, 0.123 mmol) were added and the reaction stirred at room
temperature for a further 2 hours. At this time, TLC analysis confirmed
that no starting material remained. Water
(10 mL), 3M HCl (2 mL) and methylene chloride (10 mL) were added and
organics were extracted with methylene chloride (3.times.15 mL), dried
(Na.sub.2SO.sub.4) and concentrated in vacuo to give a yellow oil.
Gradient column chromatography on silica
(crude was dry-loaded) eluting firstly with 20% and then 25% ethyl
acetate/petroleum ether isolated bis-trioxane diphenyl phosphate 14 as
a cloudy white oil (10.3 mg, 0.012 mmol, 93%). .sup.1H NMR (CDCl.sub.3,
400 MHz) .delta. 7.33 (t, 4H, J=7.7),
7.28-7.22 (m, 4H), 7.17 (t, 2H, J=7.7), 5.30 (s, 1H), 5.29 (s, 1H),
4.58-4.51 (m, 1H), 4.50-4.37 (m, 2H), 4.25 (dd, 1H, J=10.1, 2.05-1.97
(m, 2H), 1.95-1.79 (m, 4H), 1.79-1.33 (m, 16H, including two singlets
at 1.40 and 1.37), 1.32-1.17 (m, 6H),
0.98-0.78 (m, 14H); .sup.13C NMR (CDCl.sub.3, 100 MHz) .delta. 150.68
(d, 2, J=7.2), 129.67 (4), 125.11 (2), 120.17 (d, 2, J=3.9), 120.12 (d,
2, J=3.9), 103.19, 102.78, 89.45, 88.73, 81.14, 81.10, 73.80, 71.92 (d,
J=7.0), 70.80, 52.39, 52.11, 44.47,
44.09, 37.40, 37.28, 36.64, 36.58, 35.33 (d, J=7.7), 34.46, 34.42,
30.49, 30.42, 30.15, 29.38, 26.11, 26.05, 24.86, 24.79, 24.74, 24.61,
20.19, 20.09, 13.17, 12.61; .sup.31P NMR (162 MHz) .delta. -11.77; HRMS
(El, m/z) for C.sub.46H.sub.63O.sub.12PNa
requires 861.3949, found 861.3879; IR (film, cm.sup.-1) 2919, 2861,
1589, 1485, 1455, 1376, 1290, 1220, 1190, 1108, 1008, 944, 767, 686;
[.alpha.].sub.D.sup.24.1 67.6 (CHCl.sub.3, c=0.26).
Example 18
Synthesis of bis-trioxane primary
alcohol nicotinate N-oxide 15
To a stirring suspension of bis-trixane primary alcohol 4 (19.7
mg, 0.033 mmol) and nicotinic acid N-oxide (13.1 mg, 0.094 mmol) in
anhydrous methylene chloride (1 mL) was added
4-(dimethylamino)-pyridine (14.1 mg, 0.115 mmol) and
1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride (21.4 mg,
0.112 mmol). A further 1 mL of anhydrous methylene chloride was added
to wash down the flask walls and the reaction was stirred at room
temperature for 2 hours 30 minutes, at which
time TLC analysis showed full consumption of starting material. Water
(5 mL), 3M HCI solution (5 mL) and methylene chloride (5 mL) were added
and organics were extracted with methylene chloride (3.times.20 mL),
dried (Na.sub.2SO.sub.4) and concentrated
in vacuo to give a white cloudy oil (33.2 mg). Gradient column
chromatography on silica (crude was dry-loaded) eluting firstly with
ethyl acetate and then with 3% methanol/ethyl acetate isolated
bis-trioxane primary alcohol nicotinate N-oxide 15 as a
glassy solid. Treatment with hexanes (2.times.10 mL) (followed by
drying overnight under high vacuum) gave a white solid (23.6 mg, 0.032
mmol, 99%). .sup.1H NMR (CDCl.sub.3, 400 MHz) 8 8.76 (s, br, 1H), 8.33
(d, 1H, J=6.3), 7.87 (d, 1H, J=7.9), 7.36
(t, br, 1H, J=7.1), 5.31 (s, 1H), 5.27 (s, 1H), 4.61-4.51 (m, 2H), 4.46
(dd, 1H, J=10.0, J=6.2), 4.35 (dd, 1H, J=10.0, J=6.2), 2.65 (q, 1H,
J=6.8), 2.55 (q, 1H, J=6.8), 2.40-2.24 (m, 3H), 2.06-1.71 (m, 8H),
1.70-1.47 (m, 6H), 1.42-1.18 (m, 14H, including
two singlets at 1.40 and 1.38), 0.99-0.89 (m, 8H), 0.86 (apparent
triplet, 6H, J=7.0); .sup.13C NMR (CDCl.sub.3, 100 MHz) .delta. 162.65,
142.15, 140.12, 130.57, 126.41, 125.68, 103.01, 102.77, 89.63, 89.02,
81.12, 81.10, 73.00, 70.36, 68.34, 52.18,
51.98, 44.16, 43.93, 37.47, 37.45, 36.62, 36.51, 34.36, 34.33, 33.95,
30.96, 30.59, 30.56, 30.30, 25.99, 25.96, 24.90, 24.86, 24.75, 24.66,
20.16, 20.07, 12.92, 12.60; HRMS (El, m/z) for
C.sub.40H.sub.57NO.sub.11Na requires 750.3824, found 750.3858; IR
(film, cm.sup.-1) 2931, 2870, 1727, 1435, 1375, 1296, 1223, 1106, 1043,
1008, 879, 749; Mp. 104-108.degree. C. (morphological change observed
beginning at -80.degree. C.); [.alpha.].sub.D.sup.24.4 49.7
(CHCl.sub.3, c=0.205); Anal
(C.sub.40H.sub.57NO.sub.11+0.5 H.sub.2O) C, H, N.
Example 19
Synthesis of bis-trioxane phosphonic
acid monoester 16
To a solution of methylphosphonic dichloride (32.2 mg, 0.242
mmol) in anhydrous methylene chloride (1 mL) was added
4-(dimethylamino)-pyridine (5.2 mg, 0.043 mmol). The mixture was
stirred at room temperature for five minutes before addition of
bis-trioxane primary alcohol 4 (25.7 mg, 0.042 mmol) in anhydrous
methylene chloride (1.25 mL) by canula. On stirring at room temperature
for 1 hour 45 minutes, TLC analysis showed a large amount of starting
material remaining and so a second portion of
4-(dimethylamino)-pyridine (5.2 mg, 0.043 mmol) was added. Continued
stirring for a further 2 hours followed by TLC analysis showed that
starting material still remained. A third portion of
4-(dimethylamino)-pyridine (10.0 mg, 0.082 mmol) was added and
the reaction was stirred at room temperature. After 15 hours, TLC
analysis confirmed full consumption of starting material and pyridine
(0.2 mL, 2.47 mmol) was added and the mixture stirred vigorously for 1
hour before careful addition of 3M HCl (3 mL,
.about.9 mmol) and continued stirring for a further 1 hour. Methylene
chloride (5 mL) and water (5 mL) were added and organics were extracted
with methylene chloride (3.times.10 mL), dried (Na.sub.2SO.sub.4) and
concentrated in vacuo to give a white
cloudy oil (34.7 mg). Gradient column chromatography on silica (crude
was dry-loaded) eluting with 10% then 30% methanol/ethyl acetate
isolated bis-trioxane phosphonic acid monoester 16 as a glassy solid.
Treatment with hexanes (2.times.10 mL) and then
acetonitrile (3.times.10 mL) (followed by drying overnight under high
vacuum) gave a white solid (22.9 mg, 0.033 mmol, 79%). .sup.1H NMR
(CD.sub.3OD, 400 MHz) .delta. 5.39 (s, br, 2H), 4.30 (dd, 1H, J=10.4,
J=6.1), 4.20 (dd, 1H, J=10.4, J=6.1),
3.99-3.87 (m, 2H), 2.70-2.54 (m, 2H), 2.29 (t, br, 2H, J =13.9),
2.10-1.99 (m, 3H), 1.97-1.87 (m, 3H), 1.86-1.75 (m, 3H), 1.68 (d, br,
2H, J=13.2), 1.61-1.33 (m, 16H, including singlet at 1.35), 1.30-1.17
(m, 5H, including doublet (J=16.6) at 1.27),
1.02-0.94 (m, 2H), 0.97 (d, br, 6H, J=6.1), 0.90 (dd, 6H, J=7.5,
J=2.8); .sup.13C NMR (CD.sub.3OD, 100 MHz) .delta. 104.75, 104.53,
90.54, 90.22, 82.52, 82.49, 75.60, 74.84, 67.77 (d, J=5.4), 54.14,
54.00, 46.28, 46.08, 38.62, 38.60, 37.81, 37.77, 37.52
(d, J=7.6), 35.91, 35.87, 32.12, 32.10, 31.48 (2), 26.46 (2), 26.14,
26.08, 26.01, 25.99, 20.81, 20.74, 13.90, 13.66, 12.56 (d, J=139.1);
.sup.3P NMR (CD.sub.3OD, 162 MHz) .delta. 22.07; HRMS (El, m/z) for
C.sub.35H.sub.56O.sub.11PNa.sub.2 requires
729.3350, found 729.3370; IR (film, cm.sup.-1) 2940, 2862, 1449, 1372,
1196, 1188, 1090, 1037, 1008, 937, 896, 878, 826, 732; Mp.
142-147.degree. C.; [.alpha.].sub.D.sup.23.4 8.9 (CHCl.sub.3, c=3.09).
Example 20
Synthesis of bis-trioxane secondary
alcohol 17
Bis-trioxane ketone 7 (10 mg, 0.016 mmol) was dissolved in MeOH
(1 mL) and the solution was cooled to 0.degree. C. To this cooled
solution was added NaBH.sub.4 (4.2 mg, 0.112 mmol, 7.7 eq.) in 4
portions. The reaction mixture was then stirred
for 1 hour and quenched with dropwise addition of 1% AcOH--MeOH until
neutral pH was attained. The reaction mixture was then concentrated in
vacuo and the crude product charged onto a silica column. Column
chromatography gave bis-trioxane secondary
alcohol 17 as a white solid (8 mg, 84%). .sup.1H NMR (400 MHz,
CDCl.sub.3) .delta. 5.37 (s, 1H), 5.31 (s, 1H), 4.54-4.40 (m, 2H),
4.10-3.99 (bm,1H), 3.75 (s,1H), 2.76-2.60 (m, 2H), 2.38-2.24 (m, 2H),
2.08-1.20 (m, 28H), 0.96-0.84 (m, 14H); .sup.13CNMR
(100 MHz, CDCl.sub.3) .delta. 133.9, 133.7, 128.8, 128.6, 128.5, 103.3,
89.0, 88.9, 81.1, 76.2, 72.4, 71.3, 52.2, 52.4, 52.3, 44.5, 44.2, 37.6,
37.5, 36.6, 36.5, 36.3, 36.2, 34.6, 34.5, 30.6, 30.4, 26,2, 26.1, 24.9,
24.8, 24.7, 20.3, 13.2, 13.1; HRMS
(El, m/z) for C.sub.33H.sub.52O.sub.9Na.sup.+ required 615.3503, found
615.3466.
Example 21
Synthesis of bis-trioxane vicinal diol
isonicotinate N-oxide 18
To a stirring suspension of bis-trioxane vicinal diol 5 (19.4
mg, 0.031 mmol) and commercially available (Aldrich) isonicotinic acid
N-oxide (14.5 mg, 0.104 mmol) in anhydrous methylene chloride (1 mL)
was added 4-(dimethylamino)-pyridine (14.5
mg, 0.119 mmol) and 1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide
hydrochloride (23.0 mg, 0.120 mmol). A further 1 mL of anhydrous
methylene chloride was added to wash down the flask walls and the
reaction was stirred at room temperature for 1 hour 30
minutes, at which time TLC analysis showed full consumption of starting
material. Water (5 mL), 3M HCl solution (5 mL) and methylene chloride
(5 mL) were added and organics were extracted with methylene chloride
(3.times.20 mL), dried (Na.sub.2SO.sub.4)
and concentrated in vacuo to give a colorless oil. Gradient column
chromatography on silica (crude was dry-loaded) eluting firstly with
100% ethyl acetate and then with 3% methanol/ethyl acetate isolated
bis-trioxane vicinal diol isonicotinate N-oxide
18 as a colorless oil. Treatment with methylene chloride (2.times.10
mL) and then hexanes (2.times.10 mL) (followed by drying overnight
under high vacuum) gave a white solid (22.7 mg, 0.031 mmol, 99%).
.sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 8.21
(d, 2H, J =7.3), 7.92 (d, 2H, J=7.3), 5.33 (s, 1H), 5.31 (s, 1H), 4.75
(dd, 1H, J=10.3, J=6.2), 4.65-4.51 (m, 3H), 4.34 (s, br, 1H), 2.58 (qt,
1H, J=7.0), 2.56 (qt, 1H, J=7.0), 2.30 (t, br, 2H, J=13.3), 2.08-1.85
(m, 7H), 1.83-1.60 (m, 7H), 1.42-1.17 (m,
14H, including two singlets at 1.40 and 1.37), 0.99-0.93 (m, 8H), 0.89
(apparent triplet, br, 6H, J=7.7); .sup.13C NMR (100 MHz, CDCl.sub.3)
.delta. 163.04, 139.27 (2), 127.39, 126.45 (2),102.86, 102.84, 89.74,
89.41, 81.02 (2), 73.62, 70.04, 69.85,
51.91, 51.83, 43.64, 43.52, 37.58, 37.55, 36.75, 36.53, 36.46, 35.38
(2), 34.27, 34.25, 30.86, 30.82, 25.92, 25.87, 24.85 (2), 24.77 (2),
20.08, 20.02, 12.50, 12.39; HRMS (El, m/z) for
C.sub.40H.sub.57NO.sub.12Na.sup.+ requires 766.3773, found 766.3770;
IR (film, cm.sup.-1) 3483, 2931, 2861, 1719, 1608, 1443,1377, 1257,
1165, 1102, 1008, 908, 732; Mp. 114-118.degree. C.
Example 22
Synthesis of bis-trioxane isobutyric
acid 19
To a solution of bis-trioxane primary alcohol 4 (132 mg, 0.218
mmol) in ethyl acetate (4 mL), acetonitrile (4.0 mL) and H20 (1.3 mL)
was added ruthenium (III) chloride hydrate (4.5 mg, 0.022 mmol) and
sodium periodate (326 mg, 1.53 mmol, 7.0) (on
addition of ruthenium chloride the solution turned black). After
stirring for 30 mins at room temperature (the color of solution turned
to pale orange), the reaction mixture was poured into a mixture of
ethyl acetate (30 mL) and saturated aqueous
NH.sub.4Cl solution (30 mL). Organics were extracted with ethyl acetate
(2.times.30 mL), dried (MgSO.sub.4), filtered through a pad of celite
and concentrated in vacuo. Flash column chromatography on silica
eluting with 1% acetic acid in 30% ethyl
acetate/hexane isolated bis-trioxane isobutyric acid 19 as a white
solid (126 mg, 0.204 mmol, 94%). Mp=105-110.degree. C. Further
purification by medium pressure liquid chromatography (MPLC: LiChroprep
Si60 (40-63.quadrature.m)-EM Science) with the
same solvent system (1% acetic acid in 30% ethyl acetate/hexane)
removed unknown impurities and gave a white solid (118 mg, 0.190 mmol,
87%); Mp=110-113.degree. C.; .sup.1H NMR (400 MHz, CDCl.sub.3) .delta.
5.30 (s,1H), 5.29 (s, 1H), 4.30-4.20 (m, 2H),
2.92-2.84 (m, 1H), 2.75-2.55 (m, 2H), 2.35-2.23 (m, 2H), 2.15-1.95 (m,
3H), 1.94-1.50 (m,11H), 1.46-1.20 (m, 15H, including two singlets at
1.39 and 1.38), 0.94 (d, 6H, J=6.0), 0.86 (d, 6H, J=7.6), 0.98-0.86 (m,
2H); .sup.13C NMR (100 MHz, CDCl.sub.3)
.delta. 179.9, 103.3, 103.1, 89.0, 88.6, 81.1, 81.0, 74.3, 72.8, 52.3,
52.2, 44.4, 44.2, 41.8, 37.4, 37.3, 36.5, 36.5, 34.4, 31.5, 31.4, 30.3,
30.2, 25.9, 25.8, 24.7, 24.6, 20.2, 20.1, 13.1, 12.7; IR (film,
cm.sup.-1) 3500 (br), 2940, 2875, 1705, 1450,
1377, 1279, 1187, 1094, 1053, 1011, 941, 877, 826, 734; HRMS(ES) m/z
calcd for C.sub.34H.sub.52O.sub.10Na (M+Na) 643.3457, found 643.3470.
Example 23
Synthesis of bis-trioxane P-hydroxy
O-allyl ether 20
To a suspension of KH (.about.35% in mineral oil, 16 mg
(.about.5.6 mg actual), 0.14 mmol) in anhydrous diethyl ether (1.0 mL)
at 0.degree. C. was added a solution of bis-trioxane vicinal diol 5
(28.9 mg, 0.046 mmol) in diethyl ether (0.7 mL). The reaction was
stirred for 30 mins (to ensure complete formation of the alkoxide)
before addition of allyl bromide (0.012 mL, 0.14 mmol) and 18-crown-6
(2.4 mg, 0.009 mmol). The reaction was then allowed to warm to room
temperature and was stirred
until TLC analysis showed no starting material remaining. The reaction
mixture was poured into a mixture of diethyl ether (20 mL) and
saturated aqueous NH.sub.4Cl solution (20 mL) and organics were
extracted with diethyl ether (3.times.10 mL), washed
with brine, dried (MgSO.sub.4) and concentrated in vacuo. Flash column
chromatography on silica eluting with 20% ethyl acetate/hexanes
isolated bis-trioxane P-hydroxy O-allyl ether 20 as a sticky solid
(22.3 mg, 0.034 mmol, 74%); .sup.1H NMR (400 MHz,
CDCl3) 6 5.98-5.88 (m, 1H), 5.32 (s, 2H), 5.25 (ddd, 1H, J=17.2, J=3.6,
J=1.6), 5.12 (apparent doublet, br,.sub.1 H, J=10.4), 4.33-4.28 (m,
1H), 4.23-4.17 (m, 1H), 4.02-3.90 (m, 2H), 3.60-3.53 (m, 2H), 2.75-2.60
(m, 2H), 2.35-2.25 (m, 2H), 2.10-1.18 (m,
28H, including two singlets at 1.40 and 1.39); 0.94 (d, 6H, J=6.0),
0.86 (d, 3H, J=7.6), 0.84 (d, 3H, J=7.6), 0.98-0.86 (m, 2H); .sup.13C
NMR (100 MHz, CDCl.sub.3) .delta. 135.6, 116.4, 103.1, 103.0, 89.2,
88.6, 81.1, 81.0, 73.9, 73.8, 72.1, 71.5, 71.3,
52.4, 52.2, 44.5, 44.1, 37.4, 36.6, 35.8, 35.0, 34.5, 34.4, 30.7, 30.7,
26.1, 26.0, 24.8, 24.7, 20.2, 20.1, 13.2, 12.9; IR (film, cm.sup.-1)
3506, 2953, 2925, 2874, 1452, 1376,1222, 1190, 1127, 1093, 1053, 1011,
942, 878, 843, 731; HRMS(ES) m/z calcd for
C.sub.37H.sub.58NaO.sub.10 (M+Na) 685.3922, found 685.3915.
Example 24
Synthesis of bis-trioxane P-hydroxy
O-acetic acid 21
To a solution of bis-trioxane .beta.-hydroxy O-allyl ether 20
(40.3 mg, 0.061 mmol) in ethyl acetate (1.2 mL), acetonitrile (1.2 mL)
and water (0.4 mL) was added ruthenium (III) chloride hydrate
(catalytic) and sodium periodate (65.0 mg, 0.304
mmol) (on addition of ruthenium chloride the solution turned black).
The reaction was stirred at room temperature for 30 mins (the color of
solution turned to pale orange), at which time TLC analysis confirmed
complete consumption of starting material. The reaction mixture was
poured into a mixture of ethyl acetate (20 mL) and saturated aqueous
NH.sub.4Cl solution (20 mL) and organics were extracted with ethyl
acetate (2.times.20 mL), dried (MgSO.sub.4), filtered through a pad of
celite and
concentrated in vacuo. Flash column chromatography on silica eluting
with 1% acetic acid in 4% methanol/methylene chloride isolated
bis-trioxane p-hydroxy O-acetic acid 21 as a white solid (5.3 mg, 0.008
mmol, 13%). Mp=85-89.degree. C.; .sup.1H NMR
(400 MHz, CDCl.sub.3) .delta. 5.35 (s, 1H), 5.34 (s, 1H), 4.82-4.76 (m,
1H), 4.52-4.46 (m, 1H), 4.25 (d, 1H, J=17.0), 4.09 (d, 1H, J=17.0),
3.80 (d, 1H, J=9.4), 3.67 (d, 1H, J=9.4), 1.40 (s, 3H), 1.38 (s, 3H),
0.94 (d, 6H, J=6.0), 0.86 (d, 3H, J=7.6),
0.84 (d, 3H, J=7.6), 0.98-0.86 (m, 2H); HRMS(ES) m/z calcd for
C.sub.36H.sub.56NaO.sub.12(M+Na) 703.3664, found 703.3681.
Example 25
Synthesis of bis-trioxane primary
alcohol picolinate 22
To a solution of bis-trioxane primary alcohol 4 (29.9 mg, 0.049
mmol) in anhydrous methylene chloride (0.5 mL) was added picolinyl
chloride hydrochloride (22.1 mg, 0.124 mmol) and
4-(dimethylamino)-pyridine (34.2 mg, 0.280 mmol). A further
portion of anhydrous methylene chloride (1 mL) was added to wash down
the flask walls and the reaction was stirred at room temperature for 18
hours, at which time TLC analysis confirmed full consumption of
starting material. Water (5 mL), saturated
NaHCO.sub.3 solution (5 mL) and methylene chloride (5 mL) were added
and organics were extracted with methylene chloride (3.times.20 mL),
dried (Na.sub.2SO.sub.4) and concentrated in vacuo to give an off-white
solid. Gradient column chromatography on
silica (crude was dry-loaded) eluting with 30%, 40% and then 50% ethyl
acetate/petroleum ether isolated bis-trioxane primary alcohol
picolinate 22 as a colorless oil. Treatment with methylene chloride
(2.times.10 mL) and then hexanes (2.times.10 mL)
(followed by drying overnight under high vacuum) gave a white bubbly
oil (33.1 mg, 0.047 mmol, 94%). .sup.1H NMR (CDCl.sub.3, 400 MHz)
.delta. 8.74 (s, br, 1H, J=4.8), 8.12 (d,1H, J=7.8), 7.83 (dt,1H,
J=7.8, J=1.7), 7.46 (dd,1H, J=7.8, J=4.8), 5.35
(s,1H), 5.33 (s, 1H), 4.62-4.54 (m, 2H), 4.44 (dd, 1H, J=10.6, J=6.0),
4.29 (dd, 1H, J=10.6, J=6.0), 2.71 (st, 1H, J=6.9), 2.61 (st, 1H,
J=6.9), 2.49-2.38 (m, br, 1H), 2.29 (dt, 2H, J=13.9, J=3.7), 2.02-1.71
(m, 7H), 1.69-1.52 (m, 6H), 1.43-1.17 (m, 15H,
including two singlets at 1.39 and 1.37), 1.00-0.81 (m, 14H); .sup.13C
NMR (CDCl.sub.3, 100 MHz) .delta. 164.85, 149.59, 148.55, 136.93,
126.54, 125.03, 103.13, 102.90, 89.24, 88.58, 81.14, 81.10, 73.59,
71.46, 68.25, 52.39, 52.16, 44.49, 44.21, 37.33,
37.26, 36.61, 36.54, 34.47, 34.43, 34.16, 30.57, 30.46, 29.93, 29.63,
26.08, 26.04, 24.91, 24.83, 24.69, 24.60, 20.20, 20.11, 13.24, 12.87;
HRMS (El, m/z) for C.sub.40H.sub.57NO.sub.10Na requires 734.3875, found
734.3897; IR (film, cm.sup.-1) 2941, 2874,
1717, 1458, 1437, 1376, 1303, 1245, 1128, 1104, 1044, 1006, 931, 876,
743; [.alpha.].sub.D.sup.23.9 64.5 (CHCl.sub.3, c=0.270).
Example 26
Synthesis of bis-trioxane vicinal diol
nicotinate N-oxide 23
To a stirring suspension of bis-trioxane vicinal diol 5 (26.0
mg, 0.042 mmol) and commercially available (Aldrich) nicotinic acid
N-oxide (19.9 mg, 0.143 mmol) in anhydrous methylene chloride (2 mL)
was added 4-(dimethylamino)-pyridine (19.8 mg,
0.162 mmol) and 1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide
hydrochloride (32.0 mg, 0.167 mmol). A further 1 mL of anhydrous
methylene chloride was added to wash down the flask walls and the
reaction was stirred at room temperature for 3 hours, at
which time TLC analysis showed full consumption of starting material.
Water (5 mL), 3M HCl solution (5 mL) and methylene chloride (5 mL) were
added and organics were extracted with methylene chloride (3.times.20
mL), dried (Na.sub.2SO.sub.4) and
concentrated in vacuo to give a white solid. The crude material was
pre-absorbed on silica and gradient column chromatography on silica
eluting with 100% ethyl acetate, 5% methanol/ethyl acetate and then 10%
methanol/ethyl acetate isolated bis-trioxane
vicinal diol nicotinate N-oxide 23 as a colorless oil. Treatment with
methylene chloride (2.times.10 mL) and then hexanes (2.times.10 mL)
(followed by drying overnight under high vacuum) gave a white solid
(29.1 mg, 0.039 mmol, 94%)..sup.1H NMR
(CDCl.sub.3, 400 MHz) .delta. 8.80 (s, br, 1H), 8.33 (d, 1H, J=6.5),
7.89 (d, 1H, J=7.9 ), 7.35 (dd, 1h, J=6.5, J=7.9), 5.32 (s, 1H), 5.28
(s, 1H), 4.74 (dd, J=6.2, J=10.4), 4.67-4.57 (m, 2H), 4.50 (d, 1H,
J=11.2), 4.32 (s, br, 1H), 2.58 (st, 1H,
J=7.0), 2.52 (st, 1H, J=7.0), 2.34-2.23 (m, 2H), 2.06-1.61 (m, 14H),
1.43-1.18 (m, 14H, including two singlets at 1.40 and 1.36), 1.00-0.83
(m, 14H, including doublet at 0.94 (J=5.4) and apparent triplet at 0.88
(J=7.4)); .sup.13C NMR (CDCl.sub.3, 100
MHz) .delta. 162.38, 142.07, 140.18, 130.63, 126.53, 126.60, 102.82,
102.78, 89.79, 89.27, 81.02 (2), 73.32, 69.88, 69.82, 69.79, 51.92,
51.79, 43.65, 43.42, 37.48 (2), 36.87, 36.52, 36.43, 35.24, 34.25,
34.21, 30.85, 30.79, 25.87, 25.82, 24.83, 24.81,
24.72, 24.69, 20.08, 20.00, 12.51, 12.31; HRMS (El, m/z) for
C.sub.40H.sub.57NO.sub.12Na requires 766.3773, found 766.3817; IR
(film, cm.sup.-1) 2938, 2875, 1732, 1435, 1376, 1298, 1226, 1108, 1054,
1013, 941, 842, 754, 733; Mp. 116-118.degree. C.
(morphological change observed beginning at 102.degree. C.);
[.alpha.].sub.D.sup.245 33.5 (CHCl.sub.3, c=0.10); Anal
(C.sub.40H.sub.57NO.sub.12) C, H, N.
Example 27
Synthesis of bis-trioxane secondary
alcohol isonicotinate N-oxide 24
To a stirring suspension of bis-trioxane secondary alcohol 17
(21.6 mg, 0.036 mmol) and commercially available (Aldrich) isonicotinic
acid N-oxide (16.2 mg, 0.116 mmol) in anhydrous methylene chloride (1
mL) was added 4-(dimethylamino)-pyridine
(16.8 mg, 0.138 mmol) and
1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride (25.9 mg,
0.135 mmol). A further 1 mL of anhydrous methylene chloride was added
to wash down the flask walls and the reaction was stirred at room
temperature for 3
hours, at which time TLC analysis showed full consumption of starting
material. Water (5 mL), 3M HCI solution (5 mL) and methylene chloride
(5 mL) were added and organics were extracted with methylene chloride
(3.times.20 mL), dried (Na.sub.2SO.sub.4)
and concentrated in vacuo to give a colorless oil (29.5 mg). Gradient
column chromatography on silica (crude was dry-loaded) eluting firstly
with 80% ethyl acetate/petroleum ether and then with 100% ethyl acetate
isolated bis-trioxane secondary alcohol
isonicotinate N-oxide 24 as a colorless oil. Treatment with methylene
chloride (2.times.10 mL) and then hexanes (2.times.10 mL) (followed by
drying overnight under high vacuum) gave a white solid (24.4 mg, 0.034
mmol, 94%). .sup.1H NMR (CDCl.sub.3, 400
MHz) .delta. 8.18 (d, 2H, J=6.9), 7.92 (d, 2H, J=6.9), 5.48-5.39 (m,
1H), 5.35 (s, 1H), 5.31 (s, 1H), 4.46-4.37 (m, 2H), 2.65 (st, 2H,
J=6.9), 2.35-2.22 (m, 2H), 2.16-1.54 (m, 13H), 1.49-1.17 (m, 15H,
including two singlets at 1.31 and 1.26), 1.00-0.80
(m, 14H, including apparent triplet at 0.95 (J=5.6) and two doublets at
0.88 (J=7.5) and 0.83 (J=7.5)); .sup.13C NMR (CDCl.sub.3, 100 MHz)
.delta. 162.93, 139.17 (2), 127.70, 126.61 (2), 103.06, 102.99, 88.95,
88.86, 81.06 (2), 74.27, 71.73, 71.11,
52.23, 52.10, 44.21, 44.08, 37.39, 37.30, 36.51, 35.45, 34.38, 34.34,
32.72, 32.69, 30.39 (2), 25.93, 25.83, 24.72, 24.64, 24.62 (2), 20.14,
20.11, 12.99, 12.97; HRMS (El, m/z) for C.sub.39H.sub.55NO.sub.11Na
requires 736.3667, found 736.3678; IR (film,
cm.sup.-1) 2937, 2873, 1717, 1611, 1445, 1376, 1265, 1163, 1094, 1054,
1011; Mp. 114-118.degree. C. (morphological change observed beginning
at 103.degree. C.); [.alpha.].sub.D.sup.24.3 75.5 (CHCl.sub.3, c=0.13);
Anal (C.sub.39H.sub.55NO.sub.11) C, H,
N.
Example 28
Synthesis of bis-trioxane secondary
alcohol nicotinate N-oxide 25
To a stirring suspension of bis-trioxane secondary alcohol 17
(30.7 mg, 0.052 mmol) and commercially available (Aldrich) nicotinic
acid N-oxide (21.5 mg, 0.155 mmol) in anhydrous methylene chloride (1
mL) was added 4-(dimethylamino)-pyridine
(22.0 mg, 0.180 mmol) and
1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride (34.5 mg,
0.180 mmol). A further 1 mL of anhydrous methylene chloride was added
to wash down the flask walls and the reaction was stirred at room
temperature for 3
hours, at which time TLC analysis showed full consumption of starting
material. Water (5 mL), 3M HCl solution (5 mL) and methylene chloride
(5 mL) were added and organics were extracted with methylene chloride
(3.times.20 mL), dried (Na.sub.2SO.sub.4)
and concentrated in vacuo to give a colorless oil. Gradient column
chromatography on silica (crude was dry-loaded) eluting firstly with
100% ethyl acetate and then with 5% methanol/ethyl acetate isolated
bis-trioxane secondary alcohol nicotinate N-oxide
25 as a colorless oil. Treatment with methylene chloride (2.times.10
mL) and then hexanes (2.times.10 mL) (followed by drying overnight
under high vacuum) gave a white solid (37.5 mg, 0.052 mmol, 100%).
.sup.1H NMR (CDCl.sub.3, 400 MHz) .delta. 8.78
(s, 1H), 8.29 (d, 1H, J=6.5), 7.88 (d, 1H, J=8.0), 7.31 (dd, 1H, J=8.0,
J=6.5), 5.52-5.42 (m, 1H), 5.32 (s, 1H), 5.30 (s, 1H), 4.45-4.34 (m,
2H), 2.64 (st, 2H, J=6.9), 2.34-2.21 (m, 2H), 2.16-1.53 (m, 13H),
1.49-1.15 (m, 15H, including two singlets at
1.28 and 1.27), 1.00-0.80 (m, 14H, including four doublets at 0.94
(J=6.1), 0.93 (J=6.1), 0.87 (J=7.5) and 0.83 (J=7.5); .sup.13C NMR
(CDCl.sub.3, 100 MHz) .delta. 162.38, 141.93, 140.47, 130.87, 126.66,
125.45, 103.07, 102.98, 88.99, 88.77, 81.03,
81.01, 74.60, 71.93, 70.87, 52.25, 52.09, 44.22, 44.03, 37.35, 37.30,
36.52, 36.43, 34.38, 34.34, 32.93, 32.88, 30.36 (2), 25.85, 25.77,
24.73, 24.66, 24.63, 24.58, 20.13, 20.10, 13.01, 12.88; HRMS (El, m/z)
for C.sub.39H.sub.55NO.sub.11Na requires
736.3667, found 736.3715; IR (film, cm.sup.-1) 2951, 2874, 1726, 1432,
1377, 1299, 1225, 1114, 1094, 1056, 1013, 950, 876, 822, 753; Mp.
106-110.degree. C. (morphological change observed beginning at
98.degree. C.); [.alpha.].sub.D.sup.24.3 63.1
(CHCl.sub.3, c=0.225); Anal (C.sub.39H.sub.55NO.sub.11+0.5 H.sub.2O) C,
H, N.
Example 29
Synthesis of bis-trioxane primary
alcohol diethyl phosphoric acid triester 26
To a stirring solution of bis-trioxane primary alcohol 4 (26.1
mg, 0.043 mmol) in anhydrous methylene chloride (2.5 mL) was added
diethylchlorophosphate (0.12 mL, 0.860 mmol) and anhydrous pyridine
(0.07 mL, 0.860 mmol). On stirring at room
temperature for 3 hrs, TLC analysis showed full consumption of starting
material. Water (2 mL), 3M HCl (3 mL) and methylene chloride (3 mL)
were added and organics were extracted with methylene chloride
(3.times.15 mL), dried (Na.sub.2SO.sub.4) and
concentrated in vacuo to give a yellow oil. Gradient column
chromatography on silica eluting with 40% and then 50% ethyl
acetate/petroleum ether isolated bis-trioxane primary alcohol diethyl
phosphoric acid triester 26 as a colorless oil (28.1 mg, 0.038
mmol, 88%). .sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 5.30 (s, 1H),
5.27 (s, 1H), 4.40-4.35 (m, 1H), 4.24-4.06 (m, 7H), 2.68 (st, 1H,
J=7.6), 2.54 (st, 1H, J=6.8), 2.34-1.92 (m, 6H), 1.91-1.14 (m, 31H,
including a singlet at 1.38, a singlet at 1.37,
and a doublet of triplets at 1.31 (J=6.8, 0.8)), 1.02-0.68 (m, 14H,
including doublets at 0.93 (J=6.0), 0.84 (J=7.6) and 0.83 (J=7.6);
.sup.13C NMR (100 MHz, CDCl.sub.3) .delta. 103.16, 102.74, 89.35,
89.64, 81.12, 81.08, 74.00, 71.03, 69.72 (d, J=5.8),
63.54 (d, J=6.0), 63.52 (d, J=6.0), 52.40, 52.10, 44.50, 44.10, 37.36,
37.33, 36.61, 36.54, 35.36 (d, J=7.5), 34.46, 34.40, 30.51, 30.43,
30.10, 26.05, 25.99, 24.81, 24.74, 24.70, 24.62, 20.19, 20.07, 16.14
(2, d, J=6.8), 13.20, 12.67; .sup.31P NMR (162
MHz, CDCl.sub.3) 8 0.058; HRMS (El, m/z) for
C.sub.38H.sub.63O.sub.12PNa requires 765.3949, found 765.3981; IR
(film, cm.sup.-1) 2941 (m), 2880(w), 1454(w), 1373(w), 1271 (m),
1103(m), 1037 (s), 1011 (s), 878 (w), 843 (w), 665 (w);
[.alpha.].sub.D.sup.236 13.4 (CHCl.sub.3, c=0.30).
Example 30
Synthesis of bis-trioxane primary
alcohol dimethyl phosphoric acid triester 27
To a stirring solution of bis-trioxane primary alcohol 4 (21.0
mg, 0.035 mmol) in anhydrous methylene chloride (2.0 mL) was added
dimethylchlorophosphate (0.07 mL, 0.70 mmol) and anhydrous pyridine
(0.06 mL, 0.70 mmol). On stirring at room
temperature for 3 hrs, TLC analysis showed full consumption of starting
material. Water (2 mL), 3M HCl (3 mL) and methylene chloride (3 mL)
were added and organics were extracted with methylene chloride
(3.times.15 mL), dried (Na.sub.2SO.sub.4) and
concentrated in vacuo to give a yellow oil. Gradient column
chromatography on silica eluting with 40% and then 50% ethyl
acetate/petroleum ether isolated bis-trioxane primary alcohol dimethyl
phosphoric acid triester 27 as a colorless oil (13.6 mg,
0.020 mmol, 55%). .sup.1H NMR (400 MHz, CDCl.sub.3) 5.32 (s, 1H), 5.29
(s, 1H), 4.45-4.35 (m, 1H), 4.28-4.17 (m, 3H), 3.78 (d, 3H, J=10.8),
3.77 (d, 3H, J=11.2), 2.69 (st, 1H, J=7.6), 2.55 (st, 1H, J=6.4),
2.34-2.25 (m, 2H), 2.17 (s, br, 1H), 2.02-1.18
(m, 28H, including singlet at 1.37), 1.02-0.80 (m, 14H, including
doublets at 0.95 (J=6.0), 0.86 (J=7.6) and 0.85 (J=7.2)); .sup.13C NMR
(100 MHz, CDCl.sub.3) .delta. 103.17, 102.77, 89.52, 88.77, 81.16,
81.14, 73.97, 70.72, 69.91 (d, J=5.8), 54.20 (2,
d, J=6.1), 52.41, 52.10, 44.50, 44.09, 37.43, 37.38, 36.66, 36.58,
35.36 (d, J=7.9), 34.48, 34.40, 30.57, 30.50, 30.21, 29.57, 26.05,
25.98, 24.85, 24.78, 24.74, 24.67, 20.23, 20.09, 13.20, 12.64; .sup.31P
NMR (162 MHz, CDCl.sub.3) .delta. 2.10; HRMS
(El, m/z) for C.sub.36H.sub.59O.sub.12PNa requires 737.3636, found
737.3646; IR (film, cm.sup.-1) 2955 (m), 2882 (w), 1722 (w), 1452 (w),
1380 (w), 1281 (w), 1189 (w), 1109 (m), 1037 (s), 1004 (s), 879 (w),
846 (w); [.alpha.]D.sup.23.7 71.0 (CHCl.sub.3,
c=0.25).
Example 31
Synthesis of bis-trioxane primary
alcohol p-trifluoromethylbenzoate 28
To a stirring solution of bis-trioxane primary alcohol 4 (47.1
mg, 0.078 mmol) and .alpha.,.alpha.,.alpha.-trifluoro-p-toluic acid
(46.0 mg, 0.242 mmol) in anhydrous methylene chloride (1 mL) was added
4-(dimethylamino)-pyridine (33.5 mg, 0.274
mmol) and 1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride
(52.8 mg, 0.275 mmol). A further 2 mL of anhydrous methylene chloride
was added to wash down the flask walls and the reaction was stirred at
room temperature for 3 hours, at which
time TLC analysis showed full consumption of starting material. Water
(5 mL), 3M HCl solution (5 mL) and methylene chloride (5 mL) were added
and organics were extracted with methylene chloride (3.times.20 mL),
dried (Na.sub.2SO.sub.4) and concentrated
in vacuo to give a white solid (101.5 mg). Gradient column
chromatography on silica (crude was dry-loaded) eluting with 10% and
then 20% ethyl acetate/petroleum ether isolated bis-trioxane primary
alcohol p-trifluoromethylbenzoate 28 as a colorless oil
(43.7 mg, 0.056 mmol, 72%). .sup.1H NMR (CDCl.sub.3, 400 MHz) .delta.
8.16 (d, 2H, J=7.9), 7.70 (d, 2H, J=7.9), 5.32 (s, 1H), 5.27 (s, 1H),
4.60-4.42 (m, 3H), 4.37-4.29 (m, 1H), 2.70 (st, 1H, J=7.0), 2.59 (st,
1H, J=7.0), 2.47-2.36 (m, 1H), 2.30 (td,
2H, J=14.0, J=3.5), 2.06-1.72 (m, 8H), 1.69-1.49 (m, 6H), 1.43-1.13 (m,
14H, including two singlets at 1.40 and 1.39), 0.98-0.84 (m, 14H,
including two doublets at 0.95 and 0.91 (J=5.8) and two doublets at
0.87 and 0.86 (J=7.7)); .sup.13C NMR
(CDCl.sub.3, 100 MHz) .delta. 165.22, 134.15 (d, J=34.5), 133.99,
129.89 (2), 125.29 (2, d, J=3.7), 123.64 (d, J=271.6), 103.14, 102.85,
89.46, 88.76, 81.09, 81.07, 73.23, 70.98, 67.87, 52.30, 52.08, 44.34,
44.09, 37.43 (2), 36.63, 36.53, 34.41, 34.39,
33.93, 30.56, 30.45, 30.09 (2), 26.05, 25.99, 24.95, 24.87, 24.73,
24.61, 20.08, 20.06, 14.09, 12.73; HRMS (El, m/z) for
C.sub.42H.sub.57F.sub.3O.sub.10Na requires 801.3796, found 801.3847; IR
(film, cm.sup.-1) 2941, 2878, 1725, 1375, 1323, 1275, 1167,
1133, 1098, 1058, 1014, 661; [.alpha.].sub.D.sup.243 58.2 (CHCl.sub.3,
c=0.265).
Example 32
Synthesis of bis-trioxane primary
alcohol 3,5-ditrifluoromethyl benzoate 29
To a stirring solution of bis-trioxane primary alcohol 4 (48.9
mg, 0.081 mmol) and 3,5-bis(trifluoromethyl)benzoic acid (65.5 mg,
0.254 mmol) in anhydrous methylene chloride (2 mL) was added
4-(dimethylamino)-pyridine (36.0 mg, 0.295 mmol) and
1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride (55.1 mg,
0.287 mmol). A further 1 mL of anhydrous methylene chloride was added
to wash down the flask walls and the reaction was stirred at room
temperature for 15 hours, at which time TLC
analysis showed full consumption of starting material. Water (5 mL), 3M
HCl solution (5 mL) and methylene chloride (5 mL) were added and
organics were extracted with methylene chloride (3.times.20 mL), dried
(Na.sub.2SO.sub.4) and concentrated in vacuo
to give a bubbly white solid. Gradient column chromatography on silica
(crude was dry-loaded) eluting with 5%, 10% and then 20% ethyl
acetate/petroleum ether isolated bis-trioxane primary alcohol
3,5-ditrifluoromethylbenzoate 29 as a colorless oil (64.7
mg, 0.076 mmol, 95%). .sup.1H NMR (CDCl.sub.3, 400 MHz) .delta. 8.47
(s, 2H), 8.05 (s, 1H), 5.30 (s, 1H), 5.23 (s, 1H), 4.64-4.56 (m, 2H),
4.47 (dd, 1H, J=10.1, J=6.2), 4.32 (dd, 1H, J=10.1, J=6.2), 2.69 (st,
1H, J=6.9), 2.59 (st, 1H, J=6.9), 2.45-2.35
(m, 1H), 2.35-2.24 (m, 2H), 2.05-1.51 (m, 14H), 1.42-1.13 (m, 14H,
including two singlets at 1.40 and 1.37), 0.98-0.85 (m, 14H, including
two doublets at 0.94 and 0.91 (J=5.5) and a broad doublet at 0.87
(J=7.3)); .sup.13C NMR (CDCl.sub.3, 100 MHz)
.delta. 163.79, 133.08, 131.98 (2, d, J=34.0), 129.57 (2, d, J=3.0),
125.94, 122.89 (2, d, J=275.2), 103.12, 102.86, 89.45, 88.77, 81.08,
81.04, 73.31, 70.82, 68.30, 52.24, 52.04, 44.31, 44.03, 37.46 (2),
36.58, 36.47, 34.35 (2), 34.22, 30.57, 30.48,
30.21, 29.98, 25.95, 25.96, 24.92, 24.86, 24.69, 24.53, 20.06, 20.04,
13.04, 12.65; HRMS (El, m/z) for C.sub.43H.sub.56F.sub.6O.sub.10Na
requires 869.3670, found 869.3680; [.alpha.].sub.d.sup.23.4 46.8
(CHCl.sub.3, c=0.305).
Example 33
Synthesis of bis-trioxane primary
alchohol dimethylglycinate 30
To a solution of bis-trioxane primary alcohol 4 (29.2 mg, 0.048
mmol) and N,N-dimethylglycine hydrochloride (22.1 mg, 0.158 mmol) in
anhydrous methylene chloride (1 mL) was added
4-(dimethylamino)-pyridine (22.8 mg, 0.187 mmol) and
1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride (36.2 mg,
0.189 mmol). A further 1 mL of anhydrous methylene chloride was added
to wash down the flask walls and the reaction was stirred at room
temperature for 15 hours, at which time TLC
analysis showed full consumption of starting material. Water (5 mL),
saturated sodium bicarbonate solution (5 mL) and methylene chloride (5
mL) were added and organics were extracted with methylene chloride
(3.times.20 mL), dried (Na.sub.2SO.sub.4) and
concentrated in vacuo to give an off-white solid. Gradient column
chromatography on silica eluting with 60%, 70% and then 80% ethyl
acetate/petroleum ether isolated bis-trioxane primary alcohol
dimethylgylcinate 30 as a colorless oil. Treatment with
methylene chloride (2.times.10 mL) and then hexanes (2.times.10 mL)
(followed by drying overnight under high vacuum) gave a white oily
solid (23.4 mg, 0.034 mmol, 70%). .sup.1H NMR (CDCl.sub.3, 400 MHz)
.delta. 5.30 (s, br, 1H), 5.29 (s, br, 1H),
4.41-4.22 (m, 4H), 3.28 (s, 2H), 2.68 (st, 1H, J=6.8), 2.57 (st, 1H,
J=6.8), 2.44 (s, 6H), 2.37-2.15 (m, 3H), 2.06-1.96 (m, 2H), 1.95-1.85
(m, 2H), 1.83-1.54 (m, 7H), 1.53-1.19 (m, 17H, including singlet at
1.39), 1.00-0.81 (m, 14H, including two
doublets at 0.96 and 0.95 (J=5.8) and apparent triplet at 0.85
(J=6.9)); .sup.13C NMR (CDCl.sub.3,100 MHz) .delta. 169.83, 103.18,
102.87, 89.42, 88.80, 81.13, 81.10, 73.47, 71.11, 66.97, 59.52, 52.35,
52.10, 44.72 (2),44.41, 44.11, 37.45, 37.42, 34.45,
34.40, 34.01, 30.55, 30.48, 29.97 (2), 26.08, 25.99, 24.82 (2), 24.74,
24.70, 20.20, 20.10, 13.12, 12.73; HRMS (El, m/z) for
C.sub.38H.sub.61NO.sub.10Na requires 714.4188, found 714.4236; IR
(film, cm.sup.-1) 2944, 2873, 1738, 1452, 1373, 1195, 1105,
1048, 1005, 933, 877; [.alpha.].sub.D.sup.23.8 71.3 (CHCl.sub.3,
c=0.29).
Example 34
Synthesis of dihydroartemisinin 31
To a solution of artemisinin 1 (0.44 g, 1.55 mmol) in methanol
(30 mL) at 0.degree. C. was added sodium borohydride (0.47 g, 12.3
mmol) in 4 portions, each at 15 minutes intervals. After addition of
the last portion, stirring was continued for
1 hour, at which time TLC analysis confirmed no starting material
remained. Concentrated acetic acid was added dropwise until a pH of
.about.5 was achieved and the resulting mixture was then concentrated
in vacuo to give a white solid. Water (30 mL)
and methylene chloride (30 mL) were added and organics were extracted
with methylene chloride (3.times.30 mL). The combined organic extracts
were washed with saturated sodium bicarbonate solution (20 mL), dried
(Na.sub.2SO.sub.4) and concentrated in
vacuo to give a white solid (0.46 g). Gradient column chromatography on
silica (crude was dry-loaded) eluting with 40% then 50% diethyl
ether/petroleum ether isolated dihydroartemisinin 31 as a white solid
(0.38 g, 1.33 mmol, 86%, isolated as a 1.0:0.9
mixture of .beta.:.alpha.-dihydroartemisinin). .sup.1H NMR (CDCl.sub.3,
400 MHz) .delta. 5.61 (s, 1H), 5.40 (s, 0.9H), 5.31 (d, 1H, J=3.4),
4.76 (d, 0.9H, J=9.2) [only characetistic peaks listed].
Example 35
Synthesis of
.alpha.-dihydroartemisinin dimethylglycinate 32
To a solution of dihydroartemisinin 31 (25.1 mg, 0.088 mmol)
and N,N-dimethylglycine hydrochloride (32.9 mg, 0.236 mmol) in
anhydrous methylene chloride (2 mL) was added
4-(dimethylamino)-pyridine (36.5 mg, 0.299 mmol) and
1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride (55.8 mg,
0.291 mmol). A further 0.5 mL of anhydrous methylene chloride was added
to wash down the flask walls and the reaction was stirred at room
temperature for 3 hours, at which time TLC
analysis showed full consumption of starting material. Water (5 mL),
saturated sodium bicarbonate solution (5 mL) and methylene chloride (5
mL) were added and organics were extracted with methylene chloride
(3.times.20 mL), dried (Na.sub.2SO.sub.4) and
concentrated in vacuo to give an off-white solid (81.5 mg). Flash
column chromatography on silica (crude was dry-loaded) eluting with
100% ethyl acetate isolated .alpha.-dihydroartemisinin
dimethylglycinate 32 as a colorless oil (31.5 mg, 0.085 mmol,
97%). .sup.1H NMR (CDCl.sub.3, 400 MHz) .delta. 5.85 (d, 1H, J=9.9),
5.43 (s, 1H), 3.26 (AB, 2H, J=26.5, J=17.2), 2.61-2.50 (m, 1H), 2.36
(s, 6H), 2.41-2.32 (m, 1H), 2.02 (d, br,1H, J=14.4), 1.93-1.84 (m, 1H),
1.81-1.68 (m, 2H), 1.62 (dt, 1H, J=13.8,
J=4.4), 1.50-1.39 (m, 4H, including singlet at 1.42), 1.38-1.22 (m,
3H), 1.07-0.95 (m, 1H), 0.95 (d, 3H, J=5.9), 0.84 (d, 3H, J=7.1);
.sup.13C NMR (CDCl.sub.3, 100 MHz) .delta. 169.38, 104.42, 91.86,
91.48, 80.05, 59.95, 51.51, 45.20, 45.17 (2), 37.23,
36.16, 34.03, 31.80, 25.89, 24.53, 21.96, 20.18, 12.08; HRMS (El, m/z)
for C.sub.19H.sub.31NO.sub.6Na requires 392.2044, found 392.2021; IR
(film, cm.sup.-1) 2931, 2861, 2766, 1758, 1452, 1376, 1278, 1226, 1190,
1149, 1130, 1098, 1035, 1014, 926, 874,
846.
Example 36
Synthesis of
.alpha.-dihydroartemisinin isonicotinate N-oxide 33
To a stirring suspension of dihydroartemisinin 31 (33.6 mg,
0.12 mmol) and isonicotinic acid N-oxide (51.7 mg, 0.37 mmol) in
anhydrous methylene chloride (1 mL) was added
4-(dimethylamino)-pyridine (52.0 mg, 0.43 mmol) and
1-(3-(dimethylamino)propyl)-3-ethylcarbodiimide hydrochloride (81.7 mg,
0.43 mmol). A further 1 mL of anhydrous methylene chloride was added to
wash down the flask walls and the reaction was stirred at room
temperature for 4 hours, at which time TLC
analysis showed full consumption of starting material. Water (5 mL), 3M
HCl solution (5 mL) and methylene chloride (5 mL) were added and
organics were extracted with methylene chloride (3.times.20 mL), dried
(Na.sub.2SO.sub.4) and concentrated in vacuo
to give a yellow tinged colorless oil (76.7 mg). Gradient column
chromatography on silica (crude was dry-loaded) eluting with 60%, 80%,
90% and then 95% ethyl acetate/petroleum ether isolated
a-dihydroartemisinin isonicotinate N-oxide 33 as a colorless
oil. Treatment with methylene chloride (2.times.10 mL) and then hexanes
(2.times.10 mL) (followed by drying overnight under high vacuum) gave a
white solid (42.2 mg, 0.10 mmol, 88%). .sup.1H NMR (CDCl.sub.3, 400
MHz) .delta. 8.22 (d, 2H, J=7.3), 7.95
(d, 2H, J=7.3), 5.95 (d, 1H, J=9.9), 5.51 (s, 1H), 2.78-2.67 (m, 1H),
2.38 (dt, 1H, J=13.5, J=3.9), 2.08-2.00 (m, 1H), 1.95-1.64 (m, 4H),
1.55-1.22 (m, 7H, including singlet at 1.41), 1.09-0.84 (m, 7H,
including doublet at 0.97 (J=5.9) and doublet at
0.91 (J=7.1); .sup.13C NMR (CDCl.sub.3, 100 MHz) .delta. 162.11, 139.42
(2), 126.77 (2), 125.82, 104.50, 93.33, 91.60, 80.00, 51.47, 45.15,
37.21, 36.11, 33.96, 31.77, 25.83, 24.48, 21.94, 20.15, 12.16; HRMS
(El, m/z) for C.sub.21H.sub.27NO.sub.7Na
requires 428.1680, found 428.1674; IR (film, cm.sup.-1) 2925, 2872,
2359, 2343, 1733, 1612, 1486, 1444, 1262, 1165, 1132, 1091, 1053, 1036,
1016, 872, 855, 827, 768; Mp. 118-122.degree. C. (morphological change
observed beginning at 90.degree. C.);
[.alpha.].sub.D.sup.24.7 4.67 (CHCl.sub.3, c=0.465); Anal
(C.sub.21H.sub.27NO.sub.7) C, H, N.
Example 37
Synthesis of bis-trioxane allyl
tertiary alcohol 34
A solution of bis-trioxane ketone 7 (20.0 mg, 0.034 mmol) in
anhydrous tetrahydrofuran (1.5 mL) was cooled to -78.degree. C. before
addition of allyl magnesium bromide (1.0 M solution in diethyl ether,
0.140 mL, 0.140 mmol). After stirring for
one hour, TLC analysis confirmed that no starting material remained.
The reaction was quenched with 1.0 mL distilled water. The reaction
mixture was poured into a mixture of brine (20 mL) and diethyl ether
(30 mL) and the organic layer was separated,
dried (Na.sub.2SO.sub.4) and concentrated in vacuo to give a yellow
oil. Gradient column chromatography on silica eluting with 15 to 20%
ethyl acetate/hexanes isolated bis-trioxane allyl tertiary alcohol 34
as a foamy solid (20.6 mg, 0.033 mmol, 96%). .sup.1H NMR (CDCl.sub.3,
400 MHz) .delta. 5.95-5.87 (m, 1H), 5.36 (s, 1H), 5.33 (s, 1H), 5.15
(apparent d, 1H, J=17.6), 5.09 (dd, 1H, J=10.4, J=2.4), 4.80-4.63 (m,
1H), 4.60-4.54 (m, 1H), 2.70-2.41 (m, 4H), 2.34-2.27 (m, 2H), 1.40 (s,
1H), 1.39 (s, 3H),
0.95 (apparent d, 6H, J=5.6), 0.87 (apparent t, 6H, J=8.4); HRMS (ES,
m/z) calcd for C.sub.36H.sub.56O.sub.9Na (M+Na) 655.3817, found
655.3771.
Example 38
Synthesis of bis-trioxane tertiary
alcohol carboxylic acid 35
To a solution of bis-trioxane allyl tertiary alcohol 34 (20.6
mg, 0.033 mmol) in ethyl acetate (0.6 mL), acetonitrile (0.6 mL) and
H.sub.2O (0.2 mL) was added ruthenium(III) chloride hydrate (1.3 mg,
0.007 mmol) and sodium periodate (27.8 mg,
0.13 mmol) (on addition of ruthenium chloride the solution turned
black). After stirring for 30 mins at room temperature (during which
time the color of the solution changed to pale orange), the reaction
mixture was poured into a mixture of ethyl
acetate (30 mL) and saturated aqueous NH.sub.4Cl solution (30 mL).
Organics were extracted with ethyl acetate (2.times.30 mL), dried
(MgSO.sub.4), filtered through a pad of celite and concentrated in
vacuo. Flash column chromatography on silica eluting
with 1% acetic acid in 35% ethyl acetate/hexane isolated bis-trioxane
tertiary alcohol carboxylic acid 35 as a white solid (16.7 mg, 0.026
mmol, 79%). Mp=108-110.degree. C.; .sup.1H NMR (400 MHz, CDCl.sub.3)
.delta. 5.35 (s, 1H), 5.34 (s, 1H),
4.75-4.68 (m, 1H), 4.65-4.59 (m, 1H), 2.90 (ABq, 2H, J.sub.AB=15.6,
.DELTA..nu..sub.AB=39.6), 2.61-2.48 (m, 2H), 2.36-2.25 (m, 2H),
2.05-1.60 (m, 15H), 1.46-1.20 (m, 15H, including two siglets at 1.40
and 1.38), 0.98-0.82 (m, 2H), 0.96 (apparent doublet,
6H, J=5.2), 0.87 (apparent triplet, 6H, J=7.2); .sup.13C NMR (100 MHz,
CDCl.sub.3) .delta. 103.01, 102.81, 89.87, 89.59, 81.11, 81.04, 74.26,
70.65, 70.03, 51.91, 44.13, 43.57, 38.91, 37.48, 37.43, 36.54, 36.47,
34.28, 30.91, 30.76, 25.92, 24.88, 24.75,
20.06, 12.38, 12.20; HRMS(ES) m/z calcd for C.sub.35H.sub.54O.sub.11Na
(M+Na) 673.3558, found 673.3510.
Example 39
Synthesis of bis-trioxane primary
alcohol methyl carbonate 36
To a solution of bis-trioxane primary alcohol 4 (26.5 mg, 0.044
mmol) in anhydrous pyridine (1.5 mL) at -20.degree. C. was added methyl
chloroformate (0.017 mL, 0.022 mmol). The reaction was allowed to warm
to room temperature and was stirred
overnight before being quenched with distilled water (1.0 mL). The
reaction mixture was then poured into a mixture of methylene chloride
(20 mL) and saturated aqueous NH.sub.4Cl solution (20 mL). Organics
were extracted with methylene chloride
(3.times.20 mL), dried (MgSO.sub.4) and concentrated in vacuo. Flash
column chromatography on silica eluting with 20% ethyl acetate/hexanes
isolated bis-trioxane primary alcohol methyl carbonate 36 as a sticky
solid (6.4 mg, 0.010 mmol, 22%). [.alpha.].sub.D.sup.23.2 64.2
(CHCl.sub.3, c=0.17); .sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 5.30
(apparent s, 2H), 4.41-4.36 (m, 1H), 4.33 (apparent doublet, 2H,
J=4.8), 4.28-4.23 (m, 1H), 2.72-2.55 (m, 2H), 2.38-2.15 (m, 3H),
2.04-1.96 (m, 2H),
1.95-1.81 (m, 2H), 1.80-1.18 (m, 27H, including three singlets at 1.58,
1.40, 1.39), 0.97-0.80 (m, 2H), 0.95 (apparent d, 6H, J=6.0), 0.86 (d,
3H, J=7.6), 0.84 (d, 3H, J=7.2); .sup.13C NMR (100 MHz, CDCl.sub.3)
.delta. 155.79, 103.13, 102.83, 89.47,
88.86, 81.16, 81.15, 77.20, 73.60, 71.02, 70.05, 54.56, 52.38, 52.11,
44.45, 44.14, 37.42, 37.40, 36.67, 36.61, 34.48, 34.43, 34.22, 30.54,
30.49, 29.76, 26.09, 26.00, 24.83, 24.76, 24.70, 20.22, 20.11, 13.13,
12.69; IR (film, cm.sup.-1) 2952, 2876,
1748, 1443, 1377, 1270, 1105, 1039, 1008, 928, 732; HRMS(ES) m/z calcd
for C.sub.36H.sub.56O.sub.11Na (M+Na) 687.3715, found 687.3728.
Example 40
Synthesis of bis-trioxane primary
alcohol ethyl cabonate 37
To a solution of bis-trioxane primary alcohol 4 (15.5 mg, 0.026
mmol) in anhydrous pyridine (1.5 mL) at 0.degree. C. was added ethyl
chloroformate (large excess, .about.10.0 equiv). The reaction was
allowed to warm to room temperature and was
stirred overnight, before being quenched with distilled water (1.0 mL).
The reaction mixture was then poured into a mixture of methylene
chloride (20 mL) and saturated aqueous NH.sub.4Cl solution (20 mL).
Organics were extracted with methylene chloride
(3.times.20 mL), dried (MgSO.sub.4) and concentrated in vacuo. Flash
column chromatography on silica eluting with 20% ethyl acetate/hexane
isolated bis-trioxane primary alcohol ethyl carbonate 37 as a sticky
solid (8.5 mg, 0.013 mmol, 49%). [.alpha.].sub.D.sup.23.7 75.9
(CHCl.sub.3, c=0.23); .sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 5.30
(apparent s, 2H), 4.41-4.35 (m, 1H), 4.32 (apparent d, 2H, J=4.8),
4.28-4.22 (m, 1H), 4.17 (q, 2H, J=6.8), 2.73-2.55 (m, 2H), 2.38-2.15
(m, 3H), 2.04-1.96
(m, 2H), 1.96-1.18 (m, 29H, including a singlet at 1.39 and a triplet
at 1.30 (J=7.2)), 0.97-0.80 (m, 2H), 0.95 (apparent d, 6H, J=5.6), 0.85
(apparent t, 6H, J=7.2); .sup.13C NMR (100 MHz, CDCl.sub.3) .delta.
155.23, 163.13, 102.84, 89.43, 88.80,
81.15, 81.13, 73.72, 71.13, 69.80, 63.67, 52.39, 52.13, 44.48, 44.16,
37.42, 37.39, 36.67, 36.61, 34.50, 34.44, 34.26, 30.53, 30.42, 29.73,
26.10, 26.09, 24.83, 24.76, 24.70, 20.21, 20.12, 14.31, 13.17, 12.71;
IR (film, cm.sup.-1) 2939, 2872, 1744, 1453,
1377, 1260, 1105, 1038, 1008, 928, 880, 792; HRMS(ES) m/z calcd for
C.sub.37H.sub.58O.sub.11Na (M+Na) 701.3873, found 701.3919.
Example 41
Synthesis of bis-trioxane tertiary
alcohol methyl sulfonate 38
To a solution of methyl methanesulfonate (0.027 mL, 0.32 mmol)
in anhydrous tetrahydrofuran (1.5 mL) at -78.degree. C. was added
n-butyl lithium (1.3 M sol. in hexanes, 0.26 mL, 0.35 mmol). The
reaction was stirred at -78.degree. C. for 30
mins before slow addition of a solution of bis-trioxane ketone 7 (37.6
mg, 0.064 mmol) in anhydrous tetrahydrofuran (0.8 mL). After stirring
for 30 min., the reaction was quenched with distilled water (1.0 mL)
and the reaction mixture was poured into a
mixture of diethyl ether (20 mL) and saturated aqueous NH.sub.4Cl
solution (20 mL). The organic layer was then separated, dried
(MgSO.sub.4) and concentrated in vacuo. Flash column chromatography on
nsilica eluting with 30% ethyl acetate/hexanes
isolated bis-trioxane tertiary alcohol methyl sulfonate 38 as a white
solid (42.0 mg, 0.060 mmol, 94%). Mp=87-90.degree. C.; .sup.1H NMR (400
MHz, CDCl.sub.3) .delta. 5.44 (s, 1H), 5.36 (s, 1H), 4.85-4.79 (m, 1H),
4.71-4.65 (m, 2H), 3.81 (ABq, 2H,
J.sub.AB=14.4, .DELTA..nu..sub.AB=142.4), 3.96 (s, 3H), 2.76-2.67 (m,
1H), 2.59-2.91 (m, 1H), 2.38-2.15 (m, 3H), 2.06-1.82 (m, 6H), 1.81-1.19
(m, 21H, including two singlets at 1.40 and 1.37), 0.97-0.80 (m, 2H),
0.96 (d, 3H, J=5.6), 0.95 (d, 3H, J=6.0),
0.89 (d, 3H, J=7.2), 0.88 (d, 3H, J=7.2 Hz); .sup.13C NMR (100 MHz,
CDCI.sub.3) .delta. 103.17, 102.81, 89.97, 88.96, 81.12, 72.84, 70.74,
70.28, 56.60, 55.69, 52.25, 51.84, 44.27, 43.37, 39.02, 37.48, 37.39,
36.62, 36.49, 34.27, 30.74, 30.56, 25.96,
25.92, 24.91, 24.77, 24.54, 20.15, 20.12, 13.04, 12.00; IR (film,
cm.sup.-1) 3469, 2951, 2875, 1451, 1377, 1356, 1175, 1099, 1053, 1007,
911, 879, 731; HRMS(ES) m/z calcd for C.sub.35H.sub.56O.sub.12SNa
(M+Na) 723.3385, found 723.3397.
Example 42
Synthesis of bis-trioxane tertiary
alcohol isopropyl sulfonate 39
To a solution of isopropyl methanesulfonate (0.009 mL, 0.066
mmol) in anhydrous tetrahydrofuran (1.0 mL) at -78.degree. C. was added
n-butyl lithium (1.3 M sol. in hexanes, 0.055 mL, 0.073 mmol). The
reaction was stirred at -78.degree. C. for
30 mins before slow addition of a solution of bis-trioxane ketone 7
(7.8 mg, 0.013 mmol) in anhydrous tetrahydrofuran (0.4 mL). After
stirring for a further 30 mins, the reaction was quenched with
distilled water (1.0 mL) and the reaction mixture was
poured into a mixture of diethyl ether (20 mL) and saturated aqueous
NH.sub.4Cl solution (20 mL). The organic layer was then separated,
dried (MgSO.sub.4) and concentrated in vacuo. Flash column
chromatography on silica eluting with 20% ethyl
acetate/hexanes to afford bis-trioxane tertiary alcohol isopropyl
sulfonate 39 as a sticky solid (5.8 mg, 0.008 mmol, 60%). .sup.1H NMR
(400 MHz, CDCl.sub.3) .delta. 5.46 (s, 1H), 5.36 (s, 1H), 5.11 (st, 1H,
J=6.4), 4.88-4.84 (m, 1H), 4.67-4.63 (m,
2H), 3.78 (ABq, 2H, J.sub.AB=14.0, .DELTA..nu..sub.AB=146.8), 1.43 (s,
3H), 1.41 (s, 3H), 0.96 (d, 3H, J=6.0), 0.94 (d, 3H, J=6.0), 0.88(d,
3H, J=7.2), 0.87 (d, 3H, J=7.2); HRMS(ES) m/z calcd for
C.sub.37H.sub.60O.sub.12SNa (M+Na) 751.3698, found
751.3749.
Example 43
Synthesis of bis-trioxane tertiary
alcohol N,N-dimethylsulfonamide 40
To a solution of N,N-dimethyl methanesulfonamide (10.8 mg,
0.088 mmol) in anhydrous tetrahydrofuran (1.5 mL) at -78.degree. C. was
added n-butyl lithium (1.3 M sol. in hexanes, 0.072 mL, 0.097 mmol).
The reaction was stirred at -78.degree. C.
for 30 mins before slow addition of a solution of bis-trioxane ketone 7
(10.4 mg, 0.018 mmol) in anhydrous tetrahydrofuran (0.5 mL). After
stirring for a further 30 mins, the reaction was quenched with
distilled water (1.0 mL) and the reaction mixture
was poured into a mixture of diethyl ether (20 mL) and saturated
aqueous NH.sub.4Cl solution (20 mL). The organic layer was then
separated, dried (MgSO.sub.4) and concentrated in vacuo. Gradient
column chromatography on silica eluting with 25% and then
30% ethyl acetate/hexanes isolated bis-trioxane tertiary alcohol
N,N-dimethylsulfonamide 40 as a white solid (7.9 mg, 0.011 mmol, 63%).
Mp=107-110.degree. C.; [.alpha.].sub.D.sup.245 74.7 (CHCl.sub.3,
c=0.25); .sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 5.50 (s, 1H), 5.37
(s, 1H), 5.01-4.95 (m, 1H), 4.63-4.59 (s, 1H), 4.61 (m, 1H), 3.56 (ABq,
2H, J.sub.AB=13.6, .DELTA..nu..sub.AB=207.2), 2.90 (s, 6H), 2.86-2.78
(m, 1H), 2.66-2.57 (m, 1H), 2.44-2.27 (m, 3H), 2.08-1.88 (m, 4H),
1.87-1.19 (m, 23H,
including two singlets at 1.39 and 1.34), 0.97-0.80 (m, 2H), 0.95 (d,
3H, J=8.0), 0.94 (d, 3H, J=8.4 Hz), 0.88 (apparent triplet, 6H, J
=7.2); .sup.13C NMR (100 MHz, CDCl.sub.3) .delta. 103.38, 102.82,
89.87, 88.33, 81.27, 81.22, 72.80, 71.50, 71.10,
52.51, 51.93, 51.13, 44.86, 43.42, 39.22, 37.85, 37.50, 37.30, 37.00,
36.48, 34.51, 34.32, 30.58, 30.51, 26.04, 25.99, 24.98, 24.77, 24.60,
24.36, 20.24, 20.05, 13.61, 11.94; IR (film, cm.sup.-1) 3470, 2938,
2875, 1453, 1377, 1330, 1197, 1151, 1099,
1052, 1009, 955, 878, 734, 709; HRMS(ES) m/z calcd for
C.sub.36H.sub.59NO.sub.11SNa (M+Na) 736.3701, found 736.3660.
Example 44
Synthesis of bis-trioxane vicinal diol
cyclic carbonate 41
To a solution of bis-trioxane vicinal diol 5 (5.8 mg, 0.009
mmol) in methylene chloride (1.0 mL) was added 1,1'-carbonyl
diimidazole (4.5 mg, 0.028 mmol) and 4-(dimethylamino)-pyridine (3.4
mg, 0.028 mmol). The mixture was then stirred at room
temperature overnight. The reaction was poured into a mixture of
methylene chloride (20 mL) and saturated aqueous NH.sub.4Cl solution
(20 mL) and the organic layer was separated. The organics were then
washed with brine, dried (MgSO.sub.4) and
concentrated in vacuo. Flash column chromatography on silica eluting
with 25% ethyl acetate/hexanes isolated bis-trioxane vicinal diol
cyclic carbonate 41 as a white solid (5.8 mg, 0.009 mmol, 96%). .sup.1H
NMR (400 MHz, CDCl.sub.3) .delta. 5.31 (s,
1H), 5.30 (s, 1H), 4.84 (d, 1H, J=8.8), 4.67 (dd, 1H, J=6.4, J=1.6),
4.62 (dd, 1H, J=6.4, J=1.6), 4.45 (d, 1H, J=8.8), 2.65-2.48 (m, 2H),
2.35-2.25 (m, 2H), 2.38-1.58 (m, 14H), 1.46-1.18 (m, 20H, including two
singlets at 1.40 and 1.37), 0.95 (d, 6H,
J=5.6), 0.88 (d, 3H, J=7.6), 0.86 (d, 3H, J=7.6), 0.98-0.86 (m, 2H);
.sup.13C NMR (100 MHz, CDCl.sub.3) .delta. 154.9, 102.8, 102.8, 89.9,
89.6, 85.4, 81.0, 80.8, 72.2, 68.9, 68.0, 51.8, 51.8, 43.7, 43.5, 39.0,
37.5, 37.4, 36.7, 36.6, 35.6, 34.3, 34.2,
30.8, 30.7, 25.9, 25.7, 24.8, 24.7, 20.0, 12.4, 12.3; HRMS(ES) m/z
calcd for C.sub.35H.sub.52O.sub.11Na (M+Na) 671.3407, found 671.3412.
Example 45
Synthesis of bis-trioxane vicinal diol
cyclic sulfate 42
To a solution of bis-trioxane vicinal diol 5 (18.0 mg, 0.029
mmol) in anhydrous methylene chloride (2.0 mL) at 0.degree. C. was
added thionyl chloride (0.021 mL, 0.29 mmol) and triethylamine (0.064
mL, 0.46 mmol) (on addition of triethylamine
the solution turned light yellow). The reaction was stirred for one
hour, at which time TLC analysis showed complete consumption of
starting material. The reaction was quenched with distilled water (1.0
mL) and was poured into a mixture of methylene
chloride (20 mL) and saturated aqueous NH.sub.4Cl solution (20 mL). The
organic layer was then separated, dried (MgSO.sub.4) and concentrated
in vacuo to give a yellow oil. A 10 mL round-bottomed flask was charged
with the crude material, followed by
the addition of ethyl acetate (0.7 mL), and then acetonitrile (0.7 mL)
and water (0.3 mL). Ruthenium (III) chloride hydrate (1.2 mg, 0.006
mmol, 0.2 equiv--based on 5) and sodium periodate (24.8 mg, 0.116 mmol,
4.0 equiv--based on 5) were added (on
addition of ruthenium chloride the solution turned black). After
stirring for 30 mins at room temperature (the color of the solution
changed to pale orange), the reaction mixture was poured into a mixture
of ethyl acetate (30 mL) and saturated aqueous
NH.sub.4Cl solution (30 mL). The aqueous layer was extracted with ethyl
acetate (2.times.30 mL), and the combined organics were dried
(MgSO.sub.4), filtered through a pad of celite and concentrated in
vacuo. Gradient column chromatography on silica
eluting with 10%, 15% and then 20% ethyl acetate/hexanes isolated
bis-trioxane vicinal diol cyclic sulfate 42 as a white solid (17.1 mg,
0.026 mmol, 86%). Mp=107-110.degree. C.; .sup.1H NMR (400 MHz,
CDCl.sub.3) .delta. 5.37 (s, 1H), 5.30 (s, 1H),
4.84 (ABq, 2H, J.sub.AB=9.6, .DELTA..nu..sub.AB=58.4), 4.61-4.55 (m,
2H), 2.75-2.66 (m, 1H), 2.60-2.48 (m, 2H), 2.36-2.20 (m, 4H), 2.07-1.85
(m, 6H), 1.82-1.56 (m, 8H), 1.42 (s, 3H), 1.37(s, 3H), 0.97-0.80 (m,
2H), 0.96 (apparent triplet, 6H, J =6.0),
0.89 (d, 3H, J=7.6), 0.88 (d, 3H, J=7.2); .sup.13C NMR (100 MHz,
CDCl.sub.3) .delta. 103.20, 102.68, 95.49, 89.83, 89.28, 81.16, 80.86,
77.32, 68.95, 68.87, 52.19, 51.76, 44.15, 43.30, 37.53, 37.30, 36.62,
36.54, 34.57, 34.45, 34.19, 30.75, 30.23,
29.69, 25.98, 25.86, 24.83, 24.76, 20.15, 19.99, 12.92, 12.05; IR
(film, cm.sup.-1) 2941, 2876, 1455, 1380, 1209, 1114, 1093, 1009, 978,
828, 731; HRMS(ES) m/z calcd for C.sub.34H.sub.52O.sub.12SNa (M+Na)
707.3072, found 707.3087.
Example 46
Synthesis of bis-trioxane tertiary
alcohol pyridine sulfide 43
A 10 mL round-bottomed flask was charged with bis-trioxane
epoxide 6 (8.2 mg, 0.013 mmol), 4-mercaptopyridine (15 mg, 0.13 mmol)
and neutral aluminum oxide (1.0 g, type W 200 super I, Woelm Pharma,
Germany). Anhydrous diethyl ether (0.9 mL) and
methylene chloride (0.6 mL) were then added to make a slurry and the
reaction was stirred at room temperature overnight. The reaction
mixture was then filtered through a pad of celite and the solid was
washed with ethyl acetate (2.times.30 mL) before
concentration of the organics in vacuo. Flash column chromatography on
silica eluting with 45% ethyl acetate/hexanes isolated bis-trioxane
tertiary alcohol pyridine sulfide 43 as a sticky solid (3.0 mg, 0.04
mmol, 31%). .sup.1H NMR (400 MHz,
CDCl.sub.3) .delta. 8.36-8.32 (m, 2H), 7.31-7.25 (m, 2H), 5.36 (s, 1H),
5.35 (s, 1H), 4.75-4.71 (m, 1H), 4.57-4.53 (m, 1H), 4.37 (s, 1H), 3.51
(ABq, 2H, J.sub.AB=12.8, .DELTA..nu..sub.AB=34.0), 2.61-2.45 (m, 2H),
2.35-2.35(m, 2H), 2.09-1.87 (m, 6H),
1.80-1.60 (m, 10H), 1.40-1.18 (m, 12H, including two singlets at 1.35
and 1.33), 0.98-0.86 (m, 2H), 0.96 (d, 6H, J=6.0), 0.88 (d, 3H, J=7.6),
0.85 (d, 3H, J=7.6); HRMS(ES) m/z calcd for C.sub.39H.sub.57NO.sub.9SNa
(M+Na) 738.3646, found 738.3664.
Example 47
Synthesis bis-trioxane ketone O-TMS
cyanohydrin 44
To a solution of trimethylsilyl cyanide (0.003 mL, 0.023 mmol)
in anhydrous tetrahydrofuran (0.8 mL) at room temperature was added
lithium tertiary butoxide (1.0 M sol. in tetrahydrofuran, 0.002 mL,
0.002 mmol). The reaction was stirred for 10
mins at room temperature before slow addition of a solution of
bis-trioxane ketone 7 (9.0 mg, 0.015 mmol) in anhydrous tetrahydrofuran
(0.4 mL). After stirring for 30 mins, the reaction was quenched with
distilled water (1.0 mL). The reaction mixture
was then poured into a mixture of diethyl ether (20 mL) and 10% aqueous
NaHCO.sub.3 solution (20 mL) before the organic layer was separated,
dried (MgSO.sub.4) and concentrated in vacuo. Gradient column
chromatography on silica eluting with 10% and then
15% ethyl acetate/hexanes isolated bis-trioxane ketone O-TMS cyanohdrin
44 as a sticky solid (9.8 mg, 0.014 mmol, 93%). .sup.1H NMR (400 MHz,
CDCl.sub.3) .delta. 5.41 (s, 1H), 5.37 (s, 1H), 4.65-4.61 (m, 1H),
4.54-4.50 (m, 1H), 2.85-2.75 (m, 2H),
2.46-2.25 (m, 5H), 1.41 (s, 3H), 1.36 (s, 3H), 0.94 (apparent triplet,
6H, J=6.0), 0.89 (d, 3H, J=7.6),0.86 (d, 3H, J=7.6), 0.25 (s, 9H); 13C
NMR (100 MHz, CDCl.sub.3) .delta. 121.67, 103.40, 103.01, 88.14, 88.07,
80.92, 80.85, 72.73, 72.08, 70.25,
52.46, 44.68, 44.63, 38.81, 38.22, 37.23, 37.06, 36.66, 36.60, 34.51,
34.40, 30.58, 30.29, 30.23, 29.69, 26.11, 26.04, 24.56, 24.48, 24.38,
24.30, 20.24, 20.20, 13.59, 13.51, 1.31; HRMS(ES) m/z calcd for
C.sub.37H.sub.59NO.sub.9Na (M+Na) 712.3851, found
712.3863.
Example 48
Synthesis of bis-trioxane tertiary
alcohol nitrile 45
To a solution of acetonitrile (0.005 mL, 0.096 mmol) and
anhydrous tetrahydrofuran (0.8 mL) at -78.degree. C. was added LHMDS
(1.0 M sol. in THF, 0.096 mL, 0.096 mmol). The reaction was then
stirred for 30 mins at -78.degree. C. before slow
addition of a solution of bis-trioxane ketone 7 (9.5 mg, 0.016 mmol) in
anhydrous tetrahydrofuran (0.5 mL). After stirring for 30 mins, the
reaction was quenched with distilled water (1.0 mL). The reaction
mixture was then poured into a mixture of
diethyl ether (20 mL) and saturated aqueous NH.sub.4Cl solution (20
mL). The organic layer was separated, dried (MgSO.sub.4) and
concentrated in vacuo. Flash column chromatography on silica eluting
with 25% ethyl acetate/hexanes isolated bis-trioxane
tertiary alcohol nitrile 45 as a white solid (6.0 mg, 0.009 mmol,
59%)..sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 5.38 (s, 1H), 5.34 (s,
1H), 4.74-4.70 (m, 1H), 4.60-4.55 (m, 1H), 4.44 (s, 1H), 2.94 (ABq, 2H,
J.sub.AB=16.8, .DELTA..nu..sub.AB=83.2),
2.05-1.86 (m, 8H), 1.82-1.62 (m, 6H), 1.45-1.19 (m, 18H, including two
apparent singlets at 1.39 and 1.38), 0.97-0.80 (m, 2H), 0.96 (d, 6H,
J=6.0), 0.89 (d, 3H, J=7.2), 0.88 (d, 3H, J=7.2); .sup.13C NMR (100
MHz, CDCl.sub.3) .delta. 118.55, 102.94,
102.69, 90.09, 89.54, 81.13, 81.07, 72.93, 70.07, 69.65, 52.01, 51.81,
43.69, 43.30, 38.87, 37.48, 37.45, 37.06, 36.53, 34.31, 34.24, 30.87,
30.69, 29.14, 25.97, 24.88, 24.81, 24.76, 24.71, 20.06, 20.00, 12.51,
12.13; HRMS(ES) m/z calcd for
C.sub.35H.sub.53NO.sub.9Na (M+Na) 654.3613, found 654.3632.
Example 49
Synthesis of bis-trioxane methyl enol
ether 46
To a slurry of (methoxymethyl)triphenylphosphonium chloride
(400 mg, 1.2 mmol) in anhydrous tetrahydrofuran (10 mL) at 0.degree. C.
was added lithium bis(trimethylsilyl)amide (1.0 M solution in
tetrahydrofuran, 1.3 mL, 1.3 mmol) resulting in a
deep dark red color. The reaction mixture was allowed to warm to room
temperature and was stirred for 30 minutes, before being cooled to
-78.degree. C. At this time, a solution of bis-trioxane ketone 7 (270
mg, 0.46 mmol) in anhydrous tetrahydrofuran
(10 mL) was added dropwise. A color change to pale orange was observed
immediately. The reaction was stirred at -78.degree. C. for 3 hours, at
which time complete consumption of starting material was observed by
TLC analysis. The reaction mixture was
quenched with distilled water (5 mL) and organics were extracted with
methylene chloride (3.times.30 mL), dried (MgSO.sub.4) and concentrated
in vacuo to give a pale yellow oil. Flash column chromatography on
silica eluting with 20% ethyl
acetate/petroleum ether isolated bis-trioxane methyl enol ether 46 as a
white solid (220 mg, 0.35 mmol, 76%). .sup.1H NMR (CDCl.sub.3) .delta.
5.86 (s,1H), 5.45 (s, 1H), 5.42 (s,1H), 4.10-4.00 (m, 2H), 3.53 (s,
3H), 2.78-2.76 (m, 2H), 2.45-2.22 (m,
4H), 2.02-1.95 (m, 2H), 1.90-1.70 (m, 4H), 1.60-1.50 (m, 6H), 1.40-1.15
(m, 14H including a singlet at 1.39), 1.00-0.85 (m, 14H); HRMS (ES) m/z
calcd for C.sub.35H.sub.54O.sub.9Na (M+Na) 641.3660, found 641.3657.
Example 50
Synthesis of bis-trioxane aldehyde 47
A 50 mL round bottom flask was charged with bis-trioxane methyl
enol ether 46 (190 mg, 0.31 mmol), formic acid (10 mL) and diethyl
ether (15 mL). The reaction was stirred at room temperature for 8 hours
until complete consumption of starting
material was observed by TLC analysis. The reaction was then poured
into a separatory funnel containing saturated NaHCO.sub.3 (20 mL) and
diethyl ether (20 mL). Organics were extracted with diethyl ether
(3.times.30 mL), dried (MgSO.sub.4) and
concentrated in vacuo to give a pale yellow oil. Flash column
chromatography on silica eluting with 20% ethyl acetate/petroleum ether
isolated bis-trioxane aldehyde 47 as a white solid (160 mg 0.27 mmol,
87%). .sup.1H NMR (400 MHz, CDCl.sub.3) .delta. 9.85 (d, 1H, J=1.2 Hz),
5.24 (s, 1H), 5.21 (s, 1H), 4.35-4.26 (m, 2H), 2.84-2.80 (m, 1H),
2.70-2.50 (m, 2H), 2.38-2.22 (m, 2H), 2.19-2.09 (m, 2H), 2.02-1.96 (m,
4H), 1.90-1.70 (m, 4H), 1.62-1.58 (m, 6H), 1.40-1.15 (m, 12H, including
two singlets at 1.39
and 1.38), 0.98-0.82 (m, 14H); 13C NMR (100 MHz, CDCl.sub.3) .delta.
205.6, 103.8, 103.1, 89.69, 89.15, 81.47, 81.43, 73.37, 70.94, 52.54,
52.58, 47.79, 44.48, 44.20, 37.72, 37.65, 36.85 (2), 34.70, 34.65,
30.68, 30.51, 29.97, 28.92, 26.30, 26.19,
25.13, 25.11, 25.02, 24.95, 20.43, 20.37, 13.30, 12.74; HRMS (ES) m/z
calcd for C.sub.34H.sub.52O.sub.9Na (M+Na) 627.3504, found 627.3445; IR
(film, cm.sup.-1) 3100, 2800, 2250, 1650, 1400, 1300, 850, 600; Mp.
66-70.degree. C.
Example 51
Synthesis of bis-trioxane aniline 48
A 10 mL round bottom flask was charged with bis-trioxane
aldehyde 47 (25 mg, 0.041 mmol), tetrahydrofuran (1.5 mL), aniline
(0.008 mL, 0.088 mmol) and finally sodium triacetoxy borohydride (18
mg, 0.086 mmol). The reaction was stirred at room
temperature for 3 hours until complete consumption of starting material
was observed by TLC analysis. The reaction was quenched with saturated
NaHCO.sub.3 solution (1.0 mL) and organics were extracted with diethyl
ether (3.times.30 mL), dried
(MgSO.sub.4) and concentrated in vacuo to give a pale yellow oil. Flash
column chromatography on silica eluting with 15% ethyl
acetate/petroleum ether isolated bis-trioxane aniline 48 as a colorless
oil (15 mg, 0.023 mmol, 56%). .sup.1H NMR (400 MHz,
CDCl.sub.3) .delta. 7.16-7.11 (m, 2H), 6.70-6.60 (m, 3H), 5.34 (s, 1H),
5.31 (s, 1H), 4.46-4.26 (m, 2H), 3.29-3.15 (m, 2H), 2.72-2.56 (m, 2H),
2.36-2.27 (m, 2H), 2.22-2.16 (m, 1H), 2.10-1.99 (m, 2H), 1.93-1.86 (m,
2H), 1.79-1.71 (m, 5H), 1.65-1.55 (m,
5H), 1.50-1.21 (m, 14H including two singlets at 1.41 and 1.38),
0.96-0.84 (m, 14H); .sup.13C NMR (100 MHz, CDCl.sub.3) .delta. 149.1,
129.1, 116.3, 112.7, 103.2, 103.0, 89.37, 88.91, 81.17 (2), 73.90,
71.47, 52.32, 52.16, 47.34, 44.39, 44.21, 37.42,
37.28, 36.61, 36.58, 34.81, 34.42, 31.50, 31.13, 30.70, 30.54, 26.11,
26.02, 24.83, 24.77, 24.73, 24.67, 20.16, 20.13, 13.15, 12.76; HRMS
(ES) m/z calcd for C.sub.40H.sub.59NO.sub.8Na (M+Na) 704.4133, found
704.4136.
Thus, the present invention encompasses methods of treating
cancer (including but not limited to leukemia, non-small cell lung
cancer, colon cancer, central nervous system cancer, melanoma cancer,
ovarian cancer, renal cancer, prostate cancer,
and breast cancer) which include the step of administering to a patient
suffering from cancer a compound or combination of compounds recited in
claims 1-83 of PCT/US2003/030612. as published in WO 2004/028476 A2,
and incorporated herein by this
reference. The present invention further encompasses methods of
treating malaria which include the step of administering an effective
amount of a compound or combination of compounds recited in claims 1-83
of PCT/US2003/030612, as published in WO
2004/028476 A2.
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