[0001] This invention relates to novel 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic acid
derivatives of the general formula (I),

wherein M stands for hydrogen C₁₋₄ alkyl or a pharmaceutically acceptable cation,
as well as pharmaceutical compositions containing these compounds.
[0002] The invention also relates to processes for preparing the compounds of the general
formula (I) by a microbial degradation of β-sitosterol or β-sitosterol-containing
sterols of plant origin followed, if desired, by salt formation or esterification,
and for preparing pharmaceutical compositions containing the compounds of the general
formula (I).
[0003] The pharmaceutically acceptable salts of the compounds of the general formula (I)
include those formed with inorganic or organic cations such as sodium, potassium,
calcium, magnesium, aluminium, zinc, ammonium, ethylenediaminium, tris(hydroxy-methyl)-aminomethane
or tetramethylammonium.
[0004] The compounds of the general formula (I) of this invention, wherein M is as defined
above, are new and possess valuable pharmacological properties. They also serve as
starting materials for preparing pharmaceutically important steroid derivatives.
[0005] It is known that bacteria using sterols as carbon source degrade both the steroid
skeleton and the side-chain. The mechanism of the degradation of the side-chains of
sterols was elucidated by C. J. Sih and coworkers [J. Am. Chem. Soc.
89, 1957 (1967); ibid.
104, 4718 (1982); ibid
104, 4720 (1982)]. The degradation of the side-chain of cholesterol begins with hydroxylation
at the end of the side-chain. The oxidation of the hydroxyl group on the carbon atom
in position 26 leads to the formation of a carboxylic acid which is degraded by the
β-oxidation mechanism characteristic of fatty acids, resulting in a gradual shortening
of the side-chain. The degradation of the side-chain of β-sitosterol having an ethyl
group on the carbon atom in position 24 differs from that of cholesterol in that the
bacteria degrading the side-chain introduce a carboxyl group on the carbon atom in
position 28 attached to the carbon atom in position 24, then cleave the bond between
the carbon atoms in positions 24 and 28 by a β-oxidation mechanism.
[0006] The enzymatic transformations affecting the steroid skeleton, which run parallel
with the degradation of the side-chain, lead to the cleavage of the skeleton followed
by a complete degradation of the ring system. The cleavage happens in such a way that
steroid derivatives with the structure of 9α-hydroxy-1,4-dien-3-one are formed from
the sterols followed by a spontaneous rearrangement to yield therapeutically worthless
seco-steroids in which the bond between the carbon atoms in positions 9 and 10 in
ring B of the skeleton is cleaved [R. M. Dodson and R. D. Muir: J. Am. Chem. Soc.
83, 4627 (1961); K. Schubert and co-workers: Z. Naturforsch.
15b, 584 (1960)].
[0007] In the 1970s strains with changed genetic properties were prepared from sterol-utilizing
bacteria by mutagenic treatments. These strains, having no active enzymes to catalyze
the reactions initiating the degradation of the steroid skeleton
It is also known that the cell wall of bacteria can be completely or partially
removed by enzymatic hydrolysis under iso-osmotic conditions when protoplasts [J.
Tomcsik and S. Guex-Holzer: Schweiz. Z. Allg. Path. Bact.
15, 517 (1952); C. Weibull: J. Bacteriol.
66, 688 (1953)] or spheroplasts [H. Sato and co-workers: Canad. J. Microbiol.
11, 807 (1965)] are formed the cell wall of which can be regenerated. The polyethylene-glycol-induced
fusion of protoplasts or spheroplasts involves events of genetic recombination resulting
in cells with new genetic information [K. Fodor and L. Alföldi: Proc. Natl. Acad.
Sci. USA
73, 2147 (1976); P. Schaeffer and co-workers: Proc. Natl. Acad. Sci. USA
73, 2151 (1976); N. Rastogi and co-workers: J. Gen. Microbiol.
129, 1227 (1983); ibid.
137a, 135 (1986)].
[0008] Using the method of G. E. Peterson and co-workers [J. Lipid Research
3, 275 (1962)] we isolated sitosterol-degrading microorganisms from various soil samples.
Of the microorganism strains utilizing sterols we selected a Mycobacterium strain
from which, by a mutagenic treatment using UV irradiation, we produced a mutant strain
that no longer degrades the steroid skeleton.
[0009] By mutagenic treatment using N-methyl-N'-nitro-N-nitrosoguanidine we developed from
this strain genetically labelled mutant strains, such as those requiring various nutrients
(adenine, proline, valine) or those resistent to various antibiotics (e. g. streptomycin).
By an in vivo genetic recombination using spheroplast fusion with these genetically
labelled mutant strains we developed recombinant mycobacterium strains that partially
degrade the sterol side-chain. Under the code name BCS 394 a Mycobacterium strain
of this type producing new and unpublished sitosterol degradation products as main
products such as 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic acid (I, wherein M
stands for hydrogen) and 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic acid-methylester
(I, wherein M means a methyl group) was deposited with the National Collection of
Agricultural apd Industrial Microorganisms (Budapest) under the number NCAIM B(P)
001038.
[0010] The taxonomic characteristics of the Mycobacterium strain deposited under the number
NCAIM B(P) 001038 are as follows: the colonies of the microorganism are greyish white;
this organism proliferates at 45 °C, but fails to proliferate at 50 °C and in the
absence of oxygen. It efficiently utilizes ammonium chloride, calcium nitrate, sodium
nitrate and ammonium hydrogen phosphate as sole nitrogen source, as well as glucose,
glycerol, fructose, maltose, xylose, sodium succinate, sodium pyruvate and sodium
acetate as sole carbon source. It fails to utilize saccharose, starch and arabinose.
The strain is unable to degrade tyrosine and is devoid of pigmentation.
[0011] We further found unexpectedly that the new compounds of the general formula (I),
wherein M has the same meaning as above, are potent inhibitors of the biosynthesis
of cholesterol in mammals and efficiently reduce serum cholesterol levels.
[0012] In the 1980s epidemiologic studies revealed the fact that elevated serum cholesterol
levels are a major risk factor in the development of atherosclerosis in coronary arteries.
The main organ of cholesterol biosynthesis is the liver. The starting material for
the synthesis is acetic acid and synthesis route to cholesterol includes mevalonic
acid and squalene with a terpene structure as intermediates [K. Block: Angew. Chem.
77, 944 (1965); F. Lynen: Angew. Chem.
77, 929 (1965)].
[0013] Among substances inhibiting cholesterol biosynthesis a major importance has been
attributed to 8(14)-dehydro-15-oxo-sterol derivatives, of which the most effective
agent is 3β-hydroxy-5α-cholest-8(14)-en-15-one (Colestolone) whose significant serum
cholesterol-lowering effect has been proved in several animal species and also in
humans [G. J. Schroepfer jr. and co-workers: J. Biol. Chem.
263, 4110 (1988); G. J. Schroepfer jr. and co-workers: Proc. Natl. Acad. Sci. USA
79, 3042 (1982)].
[0014] The cholesterol-biosynthesis-inhibiting effect of the compounds according to the
invention is illustrated by the example of 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic
acid (I, wherein M stands for hydrogen). The inhibitory effect of this compound was
compared with that of 3β-hydroxy-5α-cholest-8(14)-en-15-one (Colestolone) by the method
of A. Endo and co-workers [Eur. J. Biochem.
77, 31 (1977); Biochim. Biophys. Acta
486, 71 (1977)] studying in rat liver homogenate the incorporation of radiolabelled acetic
acid into cholesterol.
[0015] Hannover Wistar male rats weighing 50-60 g were used for the experiment. Before the
experiments the animals were fed for a week with rat chew enriched with 5% cholestyramine,
in a reversed light cycle (light from 4 p.m. to 4 a.m., and dark from 4 a.m. to 4
p.m.). The food and water were available ad libitum.
[0016] The animals were decapitated on the day of the experiment. Livers were immersed in
ice cold Krebs/Ringer bicarbonate buffer (pH 7.4) and cut into small pieces. Using
a tissue homogenizer in a gentle mode of operation we prepared a crude liver homogenate
of which a portion equivalent to 100 mg of wet liver was weighed into glass-stoppered
tubes. The operations were carried out under constant cooling. The incubation mixture
included the liver homogenate, the Krebs/Ringer bicarbonate buffer, the sodium-(1-¹⁴C)acetate
(supplied by IZINTA; specific activity: 14.86 MBq/mg) and the (³H)cholesterol oleate
(supplied by Du Pont; specific activity: 3067 GBq/mmole). The steroids inhibiting
cholesterol biosynthesis were added to the incubation mixture in an alcoholic solution
containing albumin, as described by G. J. Schroepfer and co-workers [J. Biol. Chem.
24, 8975 (1977)]. The final volume of the incubation mixture was 2.0 ml. Incubation
went on for 2 hours in a water bath of 37 °C, then 2 ml of alcohol containing 15%
(w/v) of KOH were added to the mixture, which was then kept at 70-75 °C for further
2 hours. The lipids were extracted from the alkaline mixture by petroleum ether. After
evaporation of the solvent in nitrogen stream the dry residue was dissolved in a mixture
of acetone and ethanol, then the cholesterol was precipitated by a solution of digitonin.
The precipitate was centrifuged and dissolved in scintillation cocktail. The activity
was measured for 5 minutes using a Hitachi scintillation spectrometer. The results
obtained are presented in Table I.
Table I
| Compound |
Concentration, µM |
Inhibition, % |
| 3β-Hydroxy-5α-cholest-8(14)-en-15-one (reference) |
2.5 |
16.6 |
| 10.0 |
55.0 |
| 9α-Hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic acid |
2.5 |
65.3 |
| 10.0 |
86.3 |
[0017] The data in Table I show that the cholesterol-biosynthesis-inhibiting effect of the
compound according to the invention significantly surpasses the inhibiting effect
of the known compound 3β-hydroxy-5α-cholest-8(14)-en-15-one (Colestolone) in a rat
liver homogenate test.
[0018] In another aspect this invention relates to a process for producing new 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic
acid derivatives of the general formula (I), wherein M stands for hydrogen, C₁₋₄ alkyl
or a pharmaceutically acceptable cation, by submerged aerobic fermentation of a Mycobacterium
sp. BCS-394 microorganism strain, deposited under the number NCAIM B(P) 001038, or
a mutants of same with β-sitosterol or a sterol mixture of plant origin containing.
β-sitosterol in a nutrient medium containing utilizable carbon and nitrogen sources
as well as mineral salts, and, if desired, by isolating from the fermentation broth
the compound or compounds of the general formula (I), wherein M means hydrogen and/or
a methyl group, and, if desired, by transforming the compound of the general formula
(I), wherein M stands for hydrogen, to a compound of the general formula (I), wherein
M stands for a pharmaceutically acceptable cation or C₁₋₄ alkyl group.
[0019] According to a preferred embodiment of the present invention the Mycobacterium strain
BCS-394 deposited under the number NCAIM B(P) 001038 is cultivated in nutrient media
which contain utilizable carbon and nitrogen sources as well as mineral salts, and
which are suitable for the cultivation of fast-growing Mycobacteria.
[0020] Of the carbon sources glucose and glycerol, of the organic nitrogen sources soybean-meal,
urea and yeast extract, of the inorganic nitrogen sources ammonium chloride were advantageously
applied. It is advantageous to admix the sterol to be transformed in the form of a
suspension prepared with Tween-80 and polypropylene-glycol with the nutrient medium.
Pure β-sitosterol or a sterol mixture containing β-sitosterol, e. g. crude sitosterol
obtained from soybean oil, which is a mixture of β-sitosterol and campesterol, serve
as substrates for the microbial transformation.
[0021] The cultivation of the microorganisms and the transformation of the sterols are carried
out between 28 °C and 37 °C, preferably at 32 °C.
[0022] A major proportion of the products of sterol transformation is adsorbed on the mycobacterium
cells, a minor proportion is dissolved in the nutrient liquid. The steroids are desorbed
from the cells using organic solvents miscible with water, preferably methanol, while
the sterol transformation products in the filtrate of the fermentation broth are preferably
isolated by extraction with ethyl acetate or chlorinated hydrocarbons, such as dichloromethane.
In addition to the main products 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-carboxylic
acid and its methyl ester, the crude product obtained after the evaporation of the
solvent also contains several sterol degradation products present in minor quantities.
For the separation of the sterol transformation products column chromatography and/or
thin-layer chromatography can be preferably used. The structures of the products were
elucidated by UV, IR, ¹H-NMR and ¹³C-NMR as well as mass spectrometry.
[0023] From the compounds prepared by the process according to this invention and having
the general formula (I), wherein M means hydrogen, salts can be formed for therapeutic
application. These salts can be prepared in a manner known per se from the compound
of the general formula (I), wherein M stands for hydrogen, and a base providing the
suitable cation.
[0024] The ester derivatives according to the invention can be prepared also in a manner
known per se from the compound of the general formula (I), wherein M means hydrogen,
and a suitable C₁₋₄ alcohol. However, a representative of the compounds according
to the invention, wherein M means a methyl group in the general formula (I), can be
isolated directly from the fermentation broth.
[0025] The compounds of the general formula (I) according to the invention, wherein M stands
for hydrogen, C₁₋₄ alkyl group or a pharmaceutically acceptable cation, are highly
useful as active substances in antihypercholesteremic pharmaceutical compositions
for the treatment of e. g. atherosclerosis or hyperlipemia in humans. They can be
administered e. g. orally or parenterally, in the form of e. g. tablets, capsules
or injectable compositions. The oral mode of administration is generally preferred.
The dose may naturally depend on several factors, such as the age, body weight, the
severity of the health problem of the person to be treated and on some other factors,
but the daily dose for adults may generally range between about 100 and 3000 mg, preferably
between 300 and 1000 mg, but higher doses may also be favourably used, if necessary.
[0026] For therapeutic applications, the active compounds according to the invention are
suitably transformed to pharmaceutical compositions by mixing them with nontoxic,
inert, solid or liquid carriers and/or additives commonly used for enteral or parenteral
administration.
[0027] According to the invention, solid forms of pharmaceutical compositions suitable for
oral administration can be prepared from 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic
acid derivatives of the general formula (I), wherein M has the above meaning, by the
following method:
The pulverized active substance with an average particle size of 0.05-1.0 mm is
homogenized with additives of similar particle size, used in preparing tablets and
capsules, then the mixture is filled in hard gelatine capsules or pressed to form
tablets directly or after dry or wet granulation.
[0028] Vehicles used in the preparation of tablets and capsules were applied as additives,
preferably starch, tribasic calcium phosphate, calcium hydrogen phosphate, lactose,
glucose, cellulose, saccharose, mannitol, sorbitol or mixtures thereof; adsorbents,
preferably colloidal silicon dioxide (protected names: Aerosil, Gesilite, Cab-o-sil,
Syloid, Neosyl); excipients, preferably gelatine, acacia, cellulose ethers (methylcellulose,
carboxy-methylcellulose, ethylcellulose, ethyl-hydroxyethyl-cellulose, hydroxypropyl-methylcellulose),
pectin, sodium alginate, tragacanth, polyvinylpyrrolidone, polyvinylalcohol or their
mixtures; disintegrants, preferably starch, sodium carboxymethyl-starch, ultra-amylopectin,
alginic acid and alginates, formaldehyde-gelatine, formaldehyde-casein, pectin, bentonite,
microcrystalline cellulose or mixtures thereof; glidants, lubricants and antiadhesive
materials (preferably metal soaps, magnesium and calcium stearate), glycerol monostearate,
stearylalcohol, cetylalcohol, polyethylene glycol, talc or their mixtures.
[0029] The invention is illustrated in detail by the following Examples.
Example 1
Preparation of 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic acid and methylester
thereof
[0030] A cell suspension is prepared with 10 ml of sterile water from the 5-day old culture
of Mycobacterium sp. BCS-394 (NCAIM B(P) 001038) grown on a potato - glucose agar
slant. Five ml of this suspension are used to inoculate 800 ml of sterile MI inoculum-medium
in a 3000 ml Erlenmeyer flask. The MI medium has the following composition:
| Glucose |
8.0 g |
| Soybeanmeal |
1.6 g |
| Urea |
0.4 g |
| Yeast extract |
0.8 g |
| Ammonium chloride |
2.4 g |
| Potassium dihydrogen phosphate |
0.4 g |
| Magnesium sulfate.7H₂O |
0.4 g |
| Ferric chloride.6H₂O |
0.4 g |
| Tween-80 |
0.4 g |
| in 800 ml of tap water. |
[0031] The pH of the nutritive medium is adjusted to 7.0 before sterilization and the mixture
is sterilized at 121 °C for 45 minutes.
[0032] The flask is incubated at 32 °C for 2 days on a rotary shaker (250 r.p.m., diameter
2.5 cm). The contents of this flask are used to inoculate, in a 10 l laboratory fermentor,
4.2 l of MF medium, sterilized at 121 °C for 60 minutes.
[0033] The MF medium is prepared as follows:
50 g of glucose, 10 g of soybean-meal, 2.5 g of urea, 15 g of ammonium chloride
and 2.5 g of potassium dihydrogen phosphate are brought to boil in 1.5 l of tap water.
The basic medium prepared in this way is added, supplemented with 15 g of calcium
carbonate, under constant stirring to the molten mixture of 100 g of β-sitosterol,
40 g of polypropylene glycol, 10 g of Tween-80 and 800 ml of tap water, sterilized
at 121 °C for 1 hour, then the volume of the mixture is brought up to 4 l with boiling
tap water. The nutrient medium thus obtained is sterilized at 121 °C for 1 hour.
[0034] The inoculated culture is agitated at 32 °C for 24 hours at 750 r.p.m., while an
air flow of 100 l/hour is introduced to the fermentor. Fermentation is continued for
6 days with aeration of 300 l/hour through the broth stirred at 750 r.p.m. After the
termination of the fermentation the products of the sterol transformation are isolated
as follows.
[0035] The cells of 1 l of the broth, which initially contained 20 g of β-sitosterol, are
filtered, then the adhering sterol conversion products and the unchanged β-sitosterol
are washed off three times with 200 ml of methanol. The filtrate of the broth is extracted
with 200 ml of ethyl acetate.
[0036] After the evaporation of the pooled methanol and ethyl acetate extracts under reduced
pressure 22 g of raw product are obtained which are subjected to chromatography on
a column prepared from 400 g of silicic acid. Elution is carried out with an ethyl
acetate - n-heptane mixture in which the proportion of ethyl acetate is increased
step-wise. Fractions eluted with an ethyl acetate - n-heptane mixture containing 10%
of ethyl acetate are evaporated. After recrystallizing the residue from methanol 0.15
g of 4-stigmastadien-3-one is obtained, m.p. 89 to 90 °C.
UV spectrum (in ethanol): λ
max 243 nm (ε = 14090);
IR spectrum (in KBr): ν C=O 1678, ν C=C 1616 cm⁻¹;
¹H-NMR spectrum (in CDCl₃, δ): 5.56 s (H-4), 1.16 s (3 H-19), 0.68 s (3 H-18) ppm;
Mass spectrum: molecule-ion (
m/
z): 412;
Characteristic ions (
m/
z): 412, 229, 135, 124, 109, 95, 55, 43.
[0037] Using a solvent mixture containing 20% of ethyl acetate in n-heptane 1.05 g of unchanged
β-sitosterol are eluted from the column.
[0038] Fractions eluted with an eluent mixture containing 30% of ethyl acetate in n-heptane
are evaporated under reduced pressure. After recrystallizing the residue from methanol
1.8 g of 9α--hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic acid methyl ester are obtained,
m.p. 187 to 189 °C.
UV spectrum (in ethanol): λ
max 239 nm (ε = 21530);
IR spectrum (in KBr): ν OH 3600-3400, ν
max 3487 (9α-hydroxyl group), ν C=O 1717 (conjugated ester), 1678 (ketone in position
3), ν C=C 1615 cm⁻¹;
¹H-NMR spectrum (in C₆D₆, δ): 5.92 s (H-4), 3.46 s (3 H, OCH₃), 2.58 q (2 H-28), 1.96
s (3 H-27), 1.22 t (3 H-29), 0.95 d (3 H-21), 0.8 s (3 H-19), 0.55 s (3 H-18) ppm.
Mass spectrum: molecule-ion (
m/
z): 470;
Characteristic ions (
m/
z): 470, 438, 410, 137, 136, 134.
[0039] Fractions eluted with an eluent mixture containing 35% of ethyl acetate in n-heptane
are evaporated under reduced pressure. After recrystallizing the residue from methanol
0.15 g of 9α-hydroxy-27-nor-4-cholestene-3,24-dione is obtained, m.p. 208 to 211 °C.
UV spectrum (in ethanol): λ
max 241 nm (ε = 14800);
IR spectrum (in KBr): νOH 3555, νC=O 1705 (ketone in position 24), 1660 (ketone in
position 3), νC=C 1614 cm⁻¹;
¹H-NMR spectrum (in CDCl₃, δ): 5.86 s (H-4), 1.32 s (3 H-19), 1.05 t (3 H-26), 0.90
d (3 H-21), 0.72 s (3 H-18) ppm;
Mass spectrum: molecule-ion (
m/
z): 400;
Characteristic ions (
m/
z): 400, 151, 137, 136, 124, 122, 109, 57.
[0040] Fractions eluted with an eluent mixture containing 40% of ethyl acetate in n-heptane
are evaporated. After recrystallizing the residue from acetone 0.2 g 9α-hydroxy-3-oxo-23,24-dinor-4-cholen-22-oic
acid methyl ester is obtained, m.p. 212 to 216 °C.
UV spectrum (in ethanol): λ
max 242 nm (ε = 15860);
IR spectrum (in KBr): ν OH 3395, νC=O 1730 (ester), 1650 (ketone in position 3), νC=C
1615 cm⁻¹;
¹H-NMR spectrum (in CDCl₃, δ): 5.8 s (H-4), 3.6 s (OCH₃), 1.3 s (3 H-19), 1.2 d (3
H-21), 0.7 s (3 H-18) ppm;
Mass spectrum: molecule-ion (
m/
z): 374;
Characteristic ions (
m/
z): 374, 180, 151, 137, 136, 124, 109, 81.
[0041] Fractions eluted with an eluent mixture containing 42% of ethyl acetate in n-heptane
are evaporated. After recrystallizing the residue from methanol 0.25 g of 3-oxo-4-stigmastadien-26-oic
acid is obtained, m.p. 164 to 168 °C.
UV spectrum (in ethanol): λ
max 242 nm (ε = 14010);
IR spectrum (in KBr): νC=O 1736, 1650 (the carboxylic acid in position 26 and the
oxo group in position 3); νC=C 1616 cm⁻¹;
¹H-NMR spectrum (in CDCl₃, δ): 5.73 s (H-4), 1.19 s (3 H-19), 0.7 s (3 H-18) ppm;
Mass spectrum: molecule-ion (
m/
z): 442;
Characteristic ions (
m/
z): 442, 424, 229, 147, 124, 123, 95, 55.
[0042] Fractions eluted with an ethyl acetate-n-heptane mixture containing 45% of ethyl
acetate are evaporated under reduced pressure. The 2.5 g of residue thus obtained
are dissolved in 10 ml of methanol to which 10 ml of a mixture containing 10% (w/v)
of hydrochloric acid in methanol, and 50 ml of ethyl acetate are added. The solution
thus obtained is washed twice with 30 ml of distilled water and then evaporated under
reduced pressure. After recrystallizing the residue from methanol 2.2 g of 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic
acid are obtained, m.p. 242 to 248 °C.
UV spectrum (in ethanol): λ
max 239 (ε = 21230);
IR spectrum (in KBr): ν OH 3650-3350, ν
max 3483 (9α-hydroxy group), 3200-2200 (carboxylic acid in position 26), νC=O 1676 (ketone
in position 3 and carboxylic acid in position 26), νC=C 1616 cm⁻¹;
¹H-NMR spectrum (in C₅D₅N, δ): 6.15 d (H-4), 2.83 q (2 H-28), 2.28 s (3 H-27), 1.39
s (3 H-19), 1.39 t (3 H-29), 1.14 d (3 H-21), 0.89 s (3 H-18) ppm;
Mass spectrum: molecule-ion (
m/
z): 456;
Characteristic ions (
m/
z): 456, 438, 410, 137, 136, 124, 123, 110.
Example 2
Preparation of 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic acid and methyl ester
thereof
[0043] A cell suspension is prepared with 10 ml of sterile water from the 4-5 day old culture
of Mycobacterium sp. BCS-394 grown on a potato-glucose agar slant. Ten 100 ml portions
each of sterile MY-5 inoculum-medium in ten 500 ml Erlenmeyer flasks are inoculated
with 1 ml each of the above cell suspension.
[0044] The MY-5 medium is prepared as follows:
10 g of glycerol, 1 g of soybeanmeal, 0.5 g of urea, 1 g of ammonium chloride,
0.5 g of dipotassium hydrogen phosphate, 0.5 g of magnesium sulfate.7H₂O, 1 g of sodium
citrate and 0.05 g of ferric chloride.6H₂O are brought to boil in 300 ml of tap water.
The basis medium prepared in this way is added, under stirring, to the molten mixture
of 30 g of crude sitosterol (a 2:1 mixture of β-sitosterol and campesterol), 8 g of
polypropyleneglycol, 2 g of Tween-80 and 150 ml of tap water, sterilized at 121 °C,
then the volume of the mixture is brought up to 1 l with boiling tap water.
[0045] The flasks are shaken at 32 °C for 7 days on a horizontal shaker (250 r.p.m., diameter:
2.5 cm), then the cells are separated from the broth by means of a centrifuge. The
sterol conversion products and the unchanged crude sitosterol are washed off from
the cells by washing them three times with 200 ml of methanol each. The methanol solution
is evaporated under reduced pressure. The supernatant of the fermentation broth is
extracted with 200 ml of ethyl acetate and the extract is evaporated under reduced
pressure. By pooling the residue of the extracts 32 g of crude product are obtained.
The crude product is subjected to chromatography on a column prepared from 500 g of
silicic acid. Elution is carried out with an ethyl acetate - n-heptane mixture in
which the proportion of ethyl acetate is increased step-wise. Using an eluent mixture
containing 25% of ethyl acetate in n-heptane 2.5 g of unchanged starting material
(a 2:1 mixture of β-sitosterol and campesterol) are eluted from the column.
[0046] Fractions eluted with a mixture containing 30% of ethyl acetate in n-heptane are
evaporated under reduced pressure. After recrystallizing the residue from methanol
3.4 g of 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic acid methyl ester are obtained,
m.p. 187 to 189 °C.
[0047] The spectral characteristics of the product are the same as those presented in Example
1.
[0048] Fractions eluted with a mixture containing 35% of ethyl acetate in n-heptane are
evaporated under reduced pressure. After recrystallizing the residue from methanol
0.43 g of 9α-hydroxy-27-nor-4-cholesten-3,24-dione is obtained, m.p. 268 to 211 °C.
[0049] The spectral characteristics of the product are the same as those presented in Example
1.
[0050] Fractions eluted with a mixture containing 37% of ethyl acetate in n-heptane are
evaporated. After recrystallizing the residue from acetone 0.49 g of 9α-hydroxy-3-oxo-23,24-dinor-4-cholen-22-oic
acid methyl ester is obtained, m.p. 212 to 216 °C.
[0051] The spectral characteristics of the product are the same as those presented in Example
1.
[0052] Fractions eluted with a mixture containing 40% of ethyl acetate in n-heptane are
evaporated. After recrystallizing the residue from methanol 0.25 g of 9α-hydroxy-26,27-dinor-4-cholesten-3,24-dione
is obtained, m.p. 201 to 204 °C.
UV spectrum (in ethanol: λ
max 241 nm, (ε = 14200);
IR spectrum (in KBr): νOH 3550, νC=O 1705 (ketone in position 24), 1660 (ketone in
position 3), νC=C 1610 cm⁻¹;
¹H-NMR spectrum (in CDCl₃, δ): 5.85 s (H-4), 2.12 s (3 H-25), 1.3 s (3 H-19), 0.90
d (3 H-21), 0.7 s (3 H-18) ppm;
Mass spectrum: molecule-ion (
m/
z): 386;
Characteristic ions (
m/
z): 386, 151, 137, 136, 124, 109, 43.
[0053] Fractions eluted with a mixture containing 45% of ethyl acetate in n-heptane are
evaporated under reduced pressure. The residue is purified using preparative thin
layer chromatography with the following developing solvent: ethyl acetate and n-heptane
in a ratio of 4 to 6. The 4 g product thus obtained are dissolved in 10 ml of methanol,
the solution is acidified with 10 ml of 10% methanolic hydrochloric acid, then diluted
with 50 ml of ethyl acetate. The solution obtained is washed twice with 30 ml of distilled
water each and then evaporated under reduced pressure. After recrystallizing the residue
from methanol 3.5 g of 9α-hydroxy-3-oxo-4,24-(25)-stigmastadien-26-oic acid are obtained,
m.p. 242 to 248 °C.
[0054] The spectral characteristics of the product are the same as those presented in Example
1.
Example 3
Sodium salt of 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic acid
[0055] To a solution of 100 mg of 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic acid in
25 ml of ethanol 2.2 ml of 0.1 N sodium hydroxyd are added. After standing for 30
minutes at room temperature the solution is evaporated in vacuo. The oily residue
obtained is taken up in 10 ml of ethanol and the solution is evaporated. 5 ml of acetone
are added to the residue and the resulting sodium salt of 9α-hydroxy-3-oxo-4,24(25)-stigmastadien-26-oic
acid is filtered.
IR spectrum (in KBr): νOH 3495, νC=O 1660 (oxo group in position 3), νCOO⁻ 1572 cm⁻¹;
Mass spectrum with fast atom bombardment (FAB): [M+Na]⁺ = 501.
Patentansprüche für folgende(n) Vertragsstaat(en): AT, BE, CH, DE, FR, GB, IT, LI,
LU, NL, SE
1. 9α-Hydroxy-3-oxo-4,24(25)-stigmastadien-26-säurederivate der allgemeinen Formel (I),

worin M für Wasserstoff eine C₁₋₄-Alkylgruppe oder ein pharmazeutisch annehmbares
Kation steht.
2. 9α-Hydroxy-3-oxo-4,24(25)-stigmastadien-26-säure.
3. C₁₋₄ - Alkylester der 9α-Hydroxy-3-oxo-4,24(25)-stigmastadien-26-säure.
4. 9α-Hydroxy-3-oxo-4,24(25)-stigmastadien-26-säure-methylester.
5. Pharmazeutisch annehmbare Salze der 9α-Hydroxy-3-oxo-4,24(25)-stigmastadien-26-säure.
6. Verfahren zur Herstellung von 9α-Hydroxy-3-oxo-4,24(25)-stigmastadien-26-säurederivaten
der allgemeinen Formel (I), worin M für Wasserstoff, eine C₁₋₄-Alkylgruppe oder ein
pharmazeutisch annehmbares Kation steht, welches die Fermentation Von β-Sitosterol
oder einer β-Sitosterol enthaltenden Sterolmischung pflanzlichen Ursprungs durch eine
aerobe Submerskultur von Mycobacterium sp. BCS-394, hinterlegt unter der Nummer NCAIM
B(P) 001038, oder durch eine Mutante davon, In einem Nährmedium, das sowohl verwertbare
Kohlenstoff- und Stickstoffquellen als auch Mineralsalze enthält, umfaßt,
und, falls gewünscht, durch Isolierung der Verbindung(en) der allgemeinen Formel (I),
worin M für Wasserstoff und/oder eine Methylgruppe steht, aus der Fermentations-Nährlösung,
und, falls gewünscht, durch Umwandeln der Verbindung der allgemeinen Formel (I), worin
M für Wasserstoff steht, in eine Verbindung der allgemeinen Formel (I), worin M für
eine C₁₋₄-Alkylgruppe oder ein pharmazeutisch annehmbares Kation steht.
7. Pharmazeutische Zusammensetzung, die als aktiven Bestandteil ein 9α-Hydroxy-3-oxo-4,24(25)-stigmastadien-26-säurederivat
enthält, worin M für Wasserstoff, eine C₁₋₄ - Alkylgruppe oder ein pharmazeutisch
annehmbares Kation steht, unter Beimischung von Trägerstoffen und/oder Zusatzstoffen,
die allgemein zur Herstellung von Pharmazeutika verwendet werden.
8. Verfahren zur Herstellung von hauptsächlich anti-hypercholesterämischen pharmazeutischen
Zusammensetzungen, das die Umwandlung einer Verbindung der allgemeinen Formel (I)
, worin M dieselbe wie in Anspruch 6 definierte Bedeutung hat, zu einer pharmazeutischen
Zusammensetzung, mittels einer bei der Herstellung von Pharmazeutika bekannten Methode,
umfaßt.