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1.
The epididymis of adult rats metabolize 3H-testosterone by experiments . Thirty minutes after the injection of 100 μCi 3H-testosterone, some 10 per cent of the total radioactivity of the epididymis was found in the water-soluble fraction, whereas 90 per cent was found in the ether soluble fraction (free steroids). The free steroids were examined further and the following androgenic metabolites identified: (17β-hydroxy-4-androsten-3-one) 8, 9%, (4-androstene-3, 17-dione, 2,7%, (5α-androstane-3, 17-dione) 6,5%, (17β-hydroxy-5α-androstan-3-one) 47, 2%, (5α-androstane-3β, 17β-diol) 4, 4%, (5α-androstane-3α,17β-diol) 20, 8% and (3α-hydroxy-5α-androstan-3-one) 3,4%. The relative amount of each metabolite is given in per cent of total radioactivity in the ether soluble fraction. 相似文献
2.
A new polyhydroxysterol 1β,3β,5,6β-tetrahydroxy-5α-androstan-17-one () was isolated from the soft coral . The structure of was deduced from comparison of the spectral data with those of known 1β,3β,5α,6β-tetrahydroxysterols and confirmed by the synthesis starting from 1β,3β-dihydroxy-5,16-pregnadien-20-one () 相似文献
3.
4β,5-Epoxy-5β-androstane-3,17-dione (), 17β-hydroxy-4β,5-epoxy-5β-androstan-3-one () and 17β-acetoxy-4β,5-epoxy-5β-androstan-3-one () were treated with anhydrous hydrogen fluoride in pyridine (70% solution) at 55° and yielded the corresponding 4-en-4-ols e.g. 4-hydroxy-4-androstene-3, 17-dione ().As the reaction temperature was lowered each epoxide formed a second product which, at ?75°, was the major component of the reaction mixture and was identified as the 5α-fluoro-4α-ol derivative of the parent enone, e.g. 4α-hydroxy-5-fluoro-5α-androstane-3,17-dione (). These fluorohydrins are thermally unstable, losing hydrogen fluoride.The acetates of the fluorohydrins were also prepared, characterized, and shown to be more stable than the parent alcohols. 相似文献
4.
Bojan Hamlin Jennings Sharon Martin Boudreau Beverly Braasch Cheryl Garganta 《Steroids》1982,39(4):371-380
Both the 5α, 6α- and 5β, 6β-dichloromethylene adducts ( and ) of 3β-acetoxy-5-androsten-17-one () are produced when the latter is exposed to dichlorocarbene generated from chloroform and base by Phase Transfer Catalysis using ultrasound as a means of agitation. The 1H NMR substituent effects of 5α, 6α- and 5β, 6β-dichloromethylene on the angular methyl groups (Zürcher values) are given. The 13C NMR spectra for both compounds are presented and discussed. 相似文献
5.
A novel synthesis of 16α-hydroxy-4-androstene-3,17-dione (), 16α-hydroxy-4-androstene-3, 6,17-trione (), 17β-amino-5-androsten-3β-ol () and 17β-amino-4-androsten-3-one (14) is described. 16α-Bromoacetoxy-4-androstene-3, 17-dione (), 16α-bromoacetoxy-4-androstene-3, 6,17-trione () and 17β-bromoacetylamino-4-androsten-3-one () were synthesized as potentially selective irreversible inhibitors of androgen aromatases. 16α-Bromo-4-androstene-3,17-dione () and 16α-bromo-4-androstene-3, 6,17-trione () were converted to compounds and in 80–90% yield by controlled stereospecific hydrolysis using sodium hydroxide in aqueous pyridine. Reductive amination of 3β-hydroxy-5-androsten-17-one and 3-methoxy-3,5-androstadien-17-one () using ammonium acetate and sodium cyanohydridoborate (NaBH3CN) and a subsequent treatment with acid gave the amines and respectively, as a salt. The corresponding 17-imino compounds and were also isolated from the reaction mixtures when methanol was used as a solvent for the reaction. The 16α-hydroxyl compounds and and the 17β-amino compound were con- verted to the corresponding bromoacetyl derivatives, , , and , with bromoacetic acid and N,N'-dicyclohexylcarbodiimide. 相似文献
6.
The conversion of a 5β-pregnan-3-one into a 3-thia-A-nor-pregnane is described. The single epimer, characterized as the 5β-isomer by nmr spectroscopy, was obtained.A previous report [1] from this laboratory described the synthesis of the epimeric 3-oxa-A-norpregnan-20-ones and from A-norprogesterone. Recently, the total synthesis of the related A-nor-3-thiaestra-1,-5(10)-diene derivative has been described [2]. Continuing interest [3] in A-ring-modified steroids as probes of drug-receptor interactions prompts this report of the preparation of the 3-thia-5β-A-norpregnan-20-one . 相似文献
7.
The dinoflagellate was investigated for its sterol composition. Five of the six sterols were isolated and identified as cholest-5-en-3β-ol, (24ξ)-24-methylcholest-5-en-3β-ol, stigmasta-5,22-dien-3β-ol, (22E,24R)-4α,23,24-trimethyl-5α-cholest-22-en-3β-ol, and 4α,23ξ,24ξ-trimethyl-5α-cholestan-3β-ol. 相似文献
8.
The synthesis of 4-ethenylidene-5α-androstane-3β, 17β-diol () and of 4-ethenylidene-5α-androstane-3,17-dione () is described. Compound is a competitive inhibitor of solubilized bovine microsomal adrenal Δ5-3β-hydroxysteroid dehydrogenase, with Ki =2.7μM, and is converted by the enzyme to the corresponding 3-ketone. Compound shown to irreversibly inactivate the enzyme in a time-dependent manner (). The substrate, dehydroepiandrosterone, protects against inactivation by compound . In contrast, compound is not oxidized at the 3-position by the 3β-(and 17β)-hydroxysteroid dehydrogenase from , but is oxidized at the 17-position. Nevertheless, the 4-ethenylidene-3,17-diketone () causes irreversible time-dependent inactivation () when incubated directly with this bacterial enzyme, acting as an affinity label. 相似文献
9.
The epididymis of adult rats metabolizes 3H-testosterone by experiments . After incubation of slices from epididymal tissue for 2 hrs at 37°C, 8% of the total radioactivity was found in the water-soluble fraction, whereas 92% in the ether soluble fraction (free steroids). The free steroids were examined further and the following metabolites identified: (17β-hydroxy-4-androsten-3-one) 10,4%, (4-androstene-3,17-dione) 6,2%, (5α-androstane-3,17-dione) 7,3%, (17β-hydroxy-5α-androstane-3-one) 39,3%, (5α-androstane-3α,17β-diol) 22,7%, (5α-androstane-3β,17β-diol) 4,6% and androsterone(3α-hydroxy-5α-androstan-17-one) 8,9%. The relative amount of each metabolite is given in per cent of the total radioactivity in the ether soluble fraction. When segments (caput, corpus, cauda) of epididymis were incubated in the same way, differences in steroid metabolism were demonstrated. Characteristic for caput epididymidis was high formation of DHT (58,4%) and 3α-diol (23,5%). Corpus epididymidis showed lower formation of DHT (50,6%) and 3α-diol (12,7%), but an approximately 3 times higher formation of 5α-A-dione (12,0%) than caput (3,4%) and cauda (3,5%). Cauda epididymis showed the lowest formation of DHT (38,3%), whereas 3α-diol (29,1%) and androsterone (11,4%) formation were relatively high. The ratio between 17β-hydroxy metabolites (DHT and androstanediols) and 17-keto metabolites were much higher in the caput (8,8) than in the corpus (3,2) and cauda (3,6), indicating a higher 5α-reductase activity in this segment. 相似文献
10.
Inhibition of 5α-reduction of testosterone by an anti-androgen TSAA-291 (16β-ethyl-17β-hydroxy-4-estren-3-one) was studied in rat ventral prostates and the metabolic conversion of 3H-TSAA-291 was examined both and . In the experiment using nuclear 5α-reductase of the prostate, 5α-dihydrotestosterone formation from 3H-testosterone was inhibited in a competitive manner by the anti-androgen. In the experiment using 3H-TSAA-291, 5α-reduction of the anti-androgen occurred. One, 2 and 4 hr after an intravenous administration of 140 μCi/rat of 3H-TSAA-291 to castrated rats, the unchanged TSAA-291 accumulated in higher amounts in the ventral prostate than in the plasma, skeletal muscle and levator ani muscle, thereby indicating the selective uptake of the anti-androgen by the androgen target organ. No appreciable amounts of the 5α-reduced metabolite of TSAA-291 were detected in the prostate, thus suggesting that TSAA-291 itself may be responsible for the anti-androgenic properties. The inhibitory potency on the 5α-reductase activity of several other 16β-substituted androstane and estrane analogues was also examined. 相似文献
11.
Several cholesterol analogs structurally modified in nuclear substitutions were tested for sustaining the growth of the silkworm . 5α-Cholest-7-en-3β-ol, 5,7-cholestadien-3β-ol and cholesteryl acetate can replace cholesterol as sterol source for Considerably good growth was also obained with 5α-cholest-14-en-3β-ol and 5α-cholesta-6,8(14)-dien-3β-ol. Other sterols tested were either partially effective or ineffective as nutrients. 相似文献
12.
The and metabolism of 1,2- 3H-progesterone was studied in estrogen-stimulated and control vaginae of ovariectomized mice. Employing two-dimensional thin-layer chromatography, gas-liquid chromatography and metabolite “trapping” techniques, the major and minor pathways for progesterone metabolism were determined and shown to involve saturation of the Δ4-double bond to yield 5α-pregnane compounds and reduction of the C20 and C3 ketone groups to form 20α- and 3α- and 3β-hydroxy derivatives, respectively. The quantities of 20β-hydroxy metabolites and 5β-epimers that were detected were considered not to be significant. The major metabolites formed by untreated tissues following incubation in the presence of both high (10?6M) and low (10?8M) progesterone concentrations were 3α-hydroxy-5α-pregnan-20-one and 5α-pregnane-3,20-dione. Although these two derivatives were also found in sizable quantities in estrogen-treated tissues, a marked increase (5-fold) in the rate of C20 ketone reduction at high progesterone concentrations (10?6M) to yield 20α-hydroxy-4-pregnen-3-one was demonstrated. Following intravaginal administration of 3H-progesterone , only progesterone and 3α-hydroxy-5α-pregnan-20-one were retained in appreciable quantities through 2 hr, suggesting rapid loss of 20α-hydroxy-4-pregnen-3-one and the 5α-pregnanediols from this tissue under conditions. 相似文献
13.
George N. Phillips Florante A. Quiocho Ronald L. Sass Peter Werness Herschell Emery Furn F. Knapp G.J. Schroepfer 《Bioorganic chemistry》1976,5(1):1-10
Previous studies have established that hydride reduction of 3β-benzoyloxy-5α-cholest-8(14)-en-15-one yields two epimers (at C-15) of 5α-cholest-8(14)-en-3β,15-diol which were designated as diol A and B. Efficient enzymatic conversion of both compounds to cholesterol was observed. To determine the absolute configuration of the 15-OH function in the two compounds, the 3β-p-bromobenzoyl ester of diol B was prepared from 3β-p-bromobenzoyloxy-5α-cholest-8(14)-en-15-one by reduction with sodium borohydride. Crystals of the derivative were found to belong to the space group P1, with unit cell parameters; , , , α = 93.05°, β = 100.27°, γ = 90.82°, and one molecule per unit cell. Least-squares refinement of the structure was carried out to final R value of 0.14. The configuration of the hydroxyl group at the 15 position of diol B has been determined to be β. 相似文献
14.
A series of 12α-hydroxy steroids with varying side chains was prepared, and their 24-hour acetylation yields were compared, l2α-Hydroxy-5β-pregnan-20-one () was prepared from 3α, 12α-diacetoxy-5β~pregnan-20-one () and also by side chain degradation of 12α-acetoxy-5β-cholanoic acid (). 21-Benzyl-5β-pregnan-12α-ol () was synthesized by hydrogenation of the 21-benzylidine derivative of ketone . 23-Pheny1-5β-norcholan-12α-ol () was obtained by the Grignard reaction of 2-phenyl-ethylmagnesium bromide and ketone , dehydration, hydrogenation and hydride reduction; a similar sequence produced 20-methyl-5β-pregnan-12α-ol (). The acetylation results (Table 11) imply that branching at C-20 may be more significant for 12α-hydroxyl reactivity than side chain length or type. An additional compound with an unbranched side chain, 21-nor-5β-cholan-12α-ol (), was synthesized by a Grignard reaction on the 21-bromo intermediate . Acetylation rates determined by glc indicate (Table 111) That compounds with unbranched side chains have 12α-hydroxyl groups about ten times as reactive as their analogs with 20-methyl groups. 相似文献
15.
Antoine Pilven Marie-Lise Thieulant Bernadette Ducouret Suzanne Sampérez Pierre Jouan 《Steroids》1976,28(3):349-358
The and metabolism of by the male rat anterior pituitary was studied. A rapid and intensive conversion of 5α-androstane-3α,17β-diol into 5α-dihydrotestosterone was demonstrated, since following a 30 min. incubation time, 73 % of the recovered radioactivity were constituted by 5α-dihydrotestosterone. Studies on the subcellular distribution of steroids showed that 5α-dihydrotestosterone was the main steroid recovered except from the 105,000 × g pellet. From and experiments it was concluded that the transformation of 5α-dihydrotestosterone into 5α-androstane-3α,17β-diol was a reversible process, and that this last steroid could exert its biological action mainly 5α-dihydrotestosterone. 相似文献
16.
A novel sterol containing four hydroxy groups has been isolated from the soft coral Its structure, 5α-ergostane-3β, 5,6β,7β-tetrol (), has been deduced by spectroscopic methods and confirmed by comparison with a synthetic analog. 相似文献
17.
Eddy J. Freyne Eddy L. Esmans Josef A. Lepoivre Frank C. Alderweireldt 《Carbohydrate research》1980,78(2):235-242
Condensation of chloride severally with 3-acetyl-5-alkylpyridines, 5-alkyl-3-methoxycarbonylpyridines (alkyl = Me, Et, Pr, and iPr), 5-isopropylnicotinamide, and 3,5-diacetylpyridine bis(ethylene acetal) in acetonitrile at ?5° gave the corresponding pyridinium chlorides in excellent yield (90%). From the reaction of a series of halides with 3-acetyl-5-methyl-pyridine at room temperature, the α-nucleosides were obtained. 相似文献
18.
A mixture of testosterone-4-14C and testosterone-1,2-3H-17-glucosiduronate was intraperitoneally administered into male and female rats with bile fistulas. Biliary metabolites were separated and purififd by a combination of column chromatography, enzymic hydrolysis or solvolysis of the conjugate fractions and identification of the liberated aglycones. The injected steroids were extensively metabolized and excreted predominantly in the blue. 5β-Androstane-3α, 17β-diol was found principally in monoglucosiduronate fraction and was produced preferentially from the injected conjugate in both sexes. Very marked sex differences from the injected conjugate in both sexes. Very marked sex differences were observed in the following metabolites: Androsterone was present only in the female as monoglucosidironate, which was preferentially derived from testosterone. 5α-Androstane-3α,17β-diol was identified in both monoglucosiduronate and diconjugate fractions of the female, which was formed significanrly more from the conjugate than testosterone. These findings provide evidence that testosterone glucosiduronate could be converted directly into 5α-steroids as well as 5β-ones . In marked contrast, the major portion of testosterone was metabolized to polar steroids in the male. 相似文献
19.
Samuel A. Sholl 《Steroids》1983,41(6):769-776
3β-Hydroxysteroid activity (3Δ-HSDH) was examined in the rhesus monkey () placenta and fetal adrenal at 135 and 155–162 days of gestation. Activity was evaluated in microsomes by the conversion of [3H]pregnenolone to [3H]progesterone. There was a 7-fold increase in enzyme activity in the whole adrenal (minus medulla) between the two stages of development. Combining data from both periods, enzyme activity was greater in the outer than in the inner region of the adrenal. No stage-dependent change in placental activity was evident. The temporal patterns in 3β-HSDH activity are consistent with corticoid and progesterone patterns in the circulation. Thus, the level of 3β-HSDH activity may be rate limiting in both the fetal adrenal and placenta.Enzyme activity was assessed in incubations which included unex-tracted, heat-treated, 100,000 g tissue supernatants. In both placental and adrenal incubations, competitive inhibition was noted. Ethyl ether extracts of 100,000 g tissue supernatants also inhibited 3β-HSDH in the respective tissues. GLC analysis of these extracts revealed the presence of putative dehydroepiandrosterone. Hormone levels and the nature of the inhibition that were observed are compatible with the conclusion that dehydroepiandrosterone can inhibit the conversion of pregnenolone to progesterone . The physiological importance of this remains to be determined. 相似文献
20.
Akhil G. Jhingran R.C. Gupta Suprabhat Ray A.K. Agarwal M.M. Singh Nitya Anand 《Steroids》1983,42(6):627-634
The syntheses of (±) 2α,6β-diethyl-7α-ethynyl-3α-(-hydroxyphenyl)--bicyclo[4.3.0]nonan-7β-ol (), (±)2β,6β-diethyl-7α-ethynyl-3β-(-methoxyphenyl)--bicyclo[4.3.0]nonan-7β-ol () and (±) 2α,6β-diethyl-7α-ethynyl-3β-(-hydroxyphenyl)--bicyclo[4.3.0]nonan-7β-ol () and their derivatives, which are essentially B-seco-steroids having and geometries have been carried out. A study of their antiimplantation activities (AI) and receptor binding affinities (RBA) show that compounds are biologically most potent, followed by the corresponding and compounds. The most potent compound is active at 1 mg/kg in rats. Introduction of 7α-ethynyl group increases their AI activity; however, no significant effect on their RBA is observed. 相似文献