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1.
7 beta, 17-Dimethyltestosterone (17 beta-hydroxy-7 beta, 17-dimethyl-4-androsten-3-one) (I) was given to three subjects in oral doses of 400 mg per day for ten days. The initial dose contained the steroid tritiated in the 6 and 7 positions. Plasma levels and urinary excretion patterns were followed in all three subjects. Isolations were done on the urine, plasma, and stools of one patient. From the urine 7 beta, 17-dimethyl- 5 alpha-androstane-3 beta,17 beta-diol (VI) was isolated from the nonhydrolyzed fractions. Unchanged (I), 7 beta,17-dimethyl-5 beta-androstane-3 alpha,17 beta-diol (III) and 7 beta, 17-dimethyl-5 beta-androstane-3 beta,17 beta-diol (IV) were isolated from the nonhydrolyzed and enzyme-hydrolyzed fractions. 7 beta,17-dimethyl-5 alpha-androstane-3 alpha,17 beta-diol (V) was isolated from the enzymatic fractions. From the stools were isolated unchanged (I), (III), (IV), (V), and (VI). Unchanged (I) and its 5 alpha-dihydro derivative (17 beta-hydroxy-7 beta,17-dimethyl-5 alpha-androstan-3-one) (II) were identified in the plasma. The total recovery of radioactivity in the one patient on whom the isolations were done was 57%; 40% from the urine and 17% from the stools. 相似文献
2.
The 17-epimers of the anabolic steroids bolasterone (I), 4-chlorodehydromethyltestosterone (II), fluoxymesterone (III), furazabol (IV), metandienone (V), mestanolone (VI), methyltestosterone (VII), methandriol (VIII), oxandrolone (IX), oxymesterone (X), oxymetholone (XI), stanozolol (XII), and the human metabolites 7 alpha,17 alpha-dimethyl-5 beta-androstane-3 alpha,17 beta-diol (XIII) (metabolite of I), 6 beta-hydroxymetandienone (XIV) (metabolite of V), 17 alpha-methyl-5 beta-androst-1-ene-3 alpha,17 beta-diol (XV) (metabolite of V), 3'-hydroxystanozolol (XVI) (metabolite of XII), as well as the reference substances 17 beta-hydroxy-17 alpha-methyl-5 beta-androstan-3-one (XVII), 17 beta-hydroxy-17 alpha-methyl-5 beta-androst-1-en-3-one (XVIII) (also a metabolite of V), the four isomers 17 alpha-methyl-5 alpha-androstane-3 alpha,17 beta-diol (XIX) (also a metabolite of VI, VII, and XI), 17 alpha-methyl-5 alpha-androstane-3 beta,17 beta-diol (XX), 17 alpha-methyl-5 beta-androstane-3 alpha,17 beta-diol (XXI) (also a metabolite of V, VII, and VIII), 17 alpha-methyl-5 beta-androstane-3 beta,17 beta-diol (XXII), and 17 beta-hydroxy-7 alpha,17 alpha-dimethyl-5 beta-androstan-3-one (XXIII) were synthesized via a 17 beta-sulfate that spontaneously hydrolyzed in water to several dehydration products, and to the 17 alpha-hydroxy-17 beta-methyl epimer. The 17 beta-sulfate was prepared by reaction of the 17 beta-hydroxy-17 alpha-methyl steroid with sulfur trioxide pyridine complex. The 17 beta-methyl epimers are eluted in gas chromatography as trimethylsilyl derivatives from a capillary SE-54 or OV-1 column 70-170 methylen units before the corresponding 17 alpha-methyl epimer. The electron impact mass spectra of the underivatized and trimethylsilylated epimers are in most cases identical and only for I, II, and V was a differentiation between the 17-epimers possible. 1H nuclear magnetic resonance (NMR) spectra show for the 17 beta-methyl epimer a chemical shift for the C-18 protons (singlet) of about 0.175 ppm (in deuterochloroform) to a lower field. 13C NMR spectra display differences for the 17-epimeric steroids in shielding effects for carbons 12-18 and 20. Excretion studies with I-XII with identification and quantification of 17-epimeric metabolites indicate that the extent of 17-epimerization depends on the A-ring structure and shows a great variation for the different 17 alpha-methyl anabolic steroids. 相似文献
3.
W H Moger 《Canadian journal of physiology and pharmacology》1975,53(5):839-844
The ability of testosterone, androsterone, 5alpha-androstane-3alpha,17beta-diol, and 5alpha-androstane-3beta,17beta-diol to prevent the castration-induced rise in serum gonadotropin levels was investigated in immature male rats. Rats castrated at 30 days of age were treated once per day by subcutaneous injection of 12.5-100 mug of the steroid per 100 g body weight per day for 3 days, beginning on the day of castration. The animals were sacrificed 24 h after the last injection. Testosterone propionate, androsterone propionate, and 5alpha-androstane-3alpha,17beta-diol dipropionate were also tested at the approximate molar equivalent of 100 mug of the free alcohol form per 100 g body weight per day. Testosterone propionate and 5alpha-androstane-3alpha,17beta-diol were the only compounds tested that prevented the castration induced rise in luteinizing hormone (LH) concentrations. Testosterone propionate also inhibited the rise in follicle stimulating hormone (FSH) concentrations whereas 5alpha-androstane-3alpha,17beta-diol inhibited the rise in FSH in one but not in another experiment. These were the only compounds tested that affected serum FSH concentrations. The lower doses of testosterone tested significantly increased serum LH, but not FSH concentrations compared to castrate control animals. The highest dose tested partially inhibited the rise in serum LH concentrations. Both androsterone and androsterone propionate maintained ventral prostate weights. Although neither compound prevented the castration induced rise in serum LH, two groups receiving androsterone had serum LH concentrations significantly lower than the castrate control group. 5alpha-Androstane-3beta,17beta-diol and 5alpha-androstane-3alpha,17beta-diol dipropionate failed to maintain ventral prostate weights or prevent the rise in serum gonadotropin levels. These results indicate that 5alpha-androstane-3alpha,17beta-diol is capable of preventing the castration induced rise in serum LH concentrations in the immature male rat and thus may participate in the regulation of LH secretion in these animals. 相似文献
4.
An X-ray crystal structure determination was performed on 2 beta,4 beta-cyclo-5 alpha- and rostane-3 alpha,17 beta-diol diacetate. The parent diol, but not its 3 beta-epimer, had been shown to be an effective inhibitor of a 3 beta-hydroxysteroid dehydrogenase. 相似文献
5.
D J Lamb J R Wagle Y H Tsai A L Lee A Steinberger B M Sanborn 《Journal of steroid biochemistry》1982,16(5):653-669
This report explores the ability of various steroids to rapidly stimulate Sertoli cell RNA polymerase II activity and to compete with [3H]-androgens for nuclear and cytosol binding sites. Nuclear RNA polymerase II activity was significantly stimulated by a 1 nM concentration of the androgenic compounds testosterone, dihydrotestosterone (17 beta-hydroxy-5 alpha-androstan-3-one). R1881 (methyltrienolone) and 5 alpha, 17 beta-diol and also by the potent progestins 6 alpha methylprogesterone and R5020 (17,21-dimethyl-19-nor-4-pregna-3,20-dione). Progesterone, 17 alpha-hydroxyprogesterone, estradiol, androsterone, and 5 alpha-androstan-3 beta, 17 beta-diol were ineffective at 1 nM. Cytosol binding and nuclear accumulation of [3H]-androgen was effectively reduced by 100 fold molar excess of those androgens and progestins which stimulated RNA polymerase II activity. These data suggest that androgens and progestins bind to at least some of the same proteins in the Sertoli cell and may elicit the rapid stimulation of RNA polymerase II activity via a common mechanism. Agarose gel electrophoresis of the nuclear RNA synthesized as a result of exposure to testosterone indicated that is was heterodisperse and in part polyadenylated. Electrophoresis of the poly A+-RNA demonstrated that testosterone administration increased the incorporation of [3H]-UTP into RNA that was larger than 28 S. 相似文献
6.
Purification and properties of a new testosterone 17beta-dehydrogenase (NADP+) from guinea-pig liver.
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As a result of studies of guinea-pig live testosterone 17beta-dehydrogenase (NADP+) (EC 1.1.1.64), a new testosterone 17beta-dehydrogenase was discovered. The new enzyme was purified to a single homogeneous protein from the 105 000 g-supernatant fraction of guinea-pig liver by (NH4)2SO4 fractional precipitation and two gel-filtration stages, DEAE-cellulose column chromatography and hydroxyapatite column chromatography. It was characterized by many properties. The enzyme has almost the same properties as the classical testosterone 17beta-dehydrogenase (NADP+) (EC 1.1.1.64), with respect to cofactor requirement, pH optima for dehydrogenation, effect of phosphate ion on the NAD+-dependent reaction and molecular weight, but characteristic differences were observed in substrate-specificity between the two dehydrogenases. With various androstane derivatives, the configuration of the A/B-ring junction was closely connected with enzyme activity. 5alpha-Androstanes, such as 5alpha-androstane-3alpha,17beta-diol, 5alpha-androstane-3beta,17beta-diol and 17beta-hydroxy-5alpha-androstan-3-one, and 5beta-congeners, such as 5beta-androstane-3alpha,17beta-diol, 5beta-androstane-3beta,17beta-diol and 17beta-hydroxy-5beta-androstan-3-one, served as substrates for both the EC 1.1.1.64 enzyme and the new enzyme. The EC 1.1.1.64 enzyme oxidized testosterone more rapidly than did the new enzyme. These comparisons were based on the relative activities, apparent Km values and apparent Vmax values. 相似文献
7.
Kołek T 《The Journal of steroid biochemistry and molecular biology》1999,71(1-2):83-90
The course of the transformation of six 5-ene steroids with varying substituents at C-17 or/and C-3: dehydroepiandrosterone (DHEA), 5-androsten-3beta,17beta-diol, 17alpha-methyl-5-androsten-3beta,17beta-diol, 5-androsten-17-one, 5-androsten-3beta-ol and pregnenolone by Fusarium culmorum was investigated. Three substrates with oxygen functions at C-3 and C-17 i.e. DHEA, 5-androsten-3beta,17beta-diol and 17alpha-methyl-5-androsten-3beta,17beta-diol were hydroxylated entirely at 7alpha-axial, allylic position. The mixture of 7alpha-hydroxy- and 7alpha,15alpha-dihydroxyderivatives was formed during the transformation of pregnenolone and 5-androsten-17-one, from the latter 2alpha,7alpha-dihydroxyderivative was also obtained. 7alpha,15alpha- Dihydroxyderivative was the only product isolated from the 5-androsten-3beta-ol post-transformation mixture. The time-course of the DHEA transformation by F. culmorum shows that the substrate induces 7alpha-hydroxylase activity. DHEA was transformed by androstenedione induced F. culmorum cultures to a larger extent than by a noninduced microorganism; the selectivity of the transformation remained unchanged. 相似文献
8.
The four possible isomers 16beta-hydroxymethyl-5alpha-androstane-3beta,17beta-diol 1, 16alpha-hydroxymethyl-5alpha-androstane-3beta,17beta-diol 2, 16beta-hydroxymethyl-5alpha-androstane-3beta,17alpha-diol 3 and 16alpha-hydroxymethyl-5alpha-androstane-3beta,17alpha-diol 4 with proven configuration were converted into the corresponding 16beta-methyl-5alpha-androstane-3beta,17beta-diol 5, 16alpha-methyl-5alpha-androstane-3beta,17beta-diol 6, 16beta-methyl-5alpha-androstane-3beta,17alpha-diol 7, 16alpha-methyl-5alpha-androstane-3beta,17alpha-diol 8, furthermore into the 16beta-methyl-17beta-hydroxy-5alpha-androstane-3-one 13, 16alpha-methyl-17beta-hydroxy-5alpha-androstan-3-one 14, 16beta-methyl-17alpha-hydroxy-5alpha-androstan-3-one 15 and 16alpha-methyl-17alpha-hydroxy-5alpha-androstan-3-one 16. The steric structures of the resulting epimers were determined by means of 1H-, and 13C-NMR spectroscopy. In this way, comparison was possible with the C-16 epimers 5, 6 and 13, 14 prepared earlier by a different route, and the series of isomers could be completed with the steric structures of 16beta-methyl-17alpha-hydroxy-5alpha-androstan-3beta-ol 7 and 16alpha-methyl-17alpha-hydroxy-5alpha 8 and with their 3-keto derivatives 15 and 16. The relative binding affinities of the 16-methyl-5alpha-androstane-3beta,17-diols 5, 6, 7, 8 and 17-hydroxy-16-methyl-5alpha-androstan-3-ones 13, 14, 15, 16 were studied. The introduction of a 16-methyl substituent into 5alpha-androstane molecules substantially decreases the binding affinity to the androgen receptor and 16alpha-methyl derivatives were always bound more weakly than the 16beta-methyl isomers. 相似文献
9.
Microsomes isolated from the liver of the female rat specifically bind progesterone. The progesterone-microsomal complex shows highly specific characteristics. The binding is probably associated with the carbonyl groups at positions C-20 and C-3. Other steroids compete for microsomal binding sites less effectively. Competition for progesterone binding sites by other steroids in percentages: testosterone 33; testosterone propionate, 9; 17-methyltestosterone, 23.2; cortisol, 6.4; estradiol-17 beta, 1.8; 17 alpha-ethynyl estradiol, 4.7; mestranol, 1.0; norethynodrel, 4.5; ethisterone, 7.1; lynestrenol, 4.3; medroxyprogesterone, 23.3; medroxyprogesterone acetate, 15.2; 5 alpha-pregnane-3,20-dione, 47.6; 5 beta-pregnane-3,20-dione, 20.7; pregnenolone, 14.8; 6-methylpregnenolone, 1.2; 16 alpha-methylpregnenolone, 3.8%; 20 beta-hydroxy-4-pregnen-3-one, 2.8; 3 beta-hydroxy-5 alpha-pregnan-20-one, 5.2; 4-pregnene-3 beta, 20 beta-diol, 2.1; 11 alpha-hydroxyprogesterone 21.0; 16 alpha-hydroxyprogesterone, 7.9; 17-hydroxyprogesterone, 26.7; 16 alpha, 17-epoxyprogesterone, 2.7; 16 alpha-methylprogesterone, 3.8; 6-methylpregnenolone, 1.2; 16 alpha-methylpregnenolone, 3.8; promegestone, 27.0. 3 beta-Hydroxy-5 beta-pregnan-20-one, 3 alpha-hydroxy-5 beta-pregnan-20-one, 5-pregnene-3 beta,20 beta-diol, 5-pregnene-3 beta, 20 alpha-diol; 5 alpha-pregnane-3 beta, 20 beta-diol, 5 alpha-pregnane-3 beta, 20 alpha-diol, 5 beta-pregnane-3 alpha, 20 alpha-diol, 5 beta-pregnane-3 alpha, 20 alpha-diol diacetate, 5 beta-pregnane-3 alpha, 20 beta-diol, 3 alpha, 17-dihydroxy-5 beta-pregnan-20-one, 17-hydroxypregnenolone, 6-methyl-17-hydroxypregnenolone, pregnenolone-16 alpha-carbonitrile, dihydrotestosterone and cholesterol show no competition at all. The varying degree of competition by different steroids is unrelated to their lipid solubility. 相似文献
10.
17 alpha-Methyltestosterone and the reduced metabolites, 17 alpha-methyl-5 alpha-androstane-3 alpha, 17 beta-diol, 17 alpha-methyl-5 alpha-androstane-3 beta, 17 beta-diol and 17 alpha-methyl-5 beta-androstane-3 alpha, 17 beta-diol, together with three hydroxylated metabolites, 17 alpha-methyl-5 beta-androstane-3 alpha, 16 alpha, 17 beta-triol, 17 alpha-methyl-5 beta-androstane-3 alpha, 16 beta, 17 beta-triol and a new metabolite, 17 alpha-methyl-5 alpha-androstane-3 beta, 6 alpha, 17 beta-triol, were isolated and identified in the urine of rabbits dosed with 17 alpha-methyltestosterone. No hydroxylated 5 alpha-metabolite of 17 alpha-methyltestosterone has been identified previously. No of 17 alpha-methyltestosterone has been identified previously. No evidence for epimerization at the C-17 position was observed. 相似文献
11.
The synthesis of 1alpha-hydroxypregnacalciferol, a side chain analog of 1alpha,25-dihydroxycholecalciferol (1alpha,25-dihydroxyvitamin D3), is described. Pregnenolone acetate was converted in five steps to 5-pregnen-1alpha,3beta-diol. Conversion of the diol to pregna-5,7-diene-1alpha,3beta diol diacetate followed by ultraviolet irradiation gave the corresponding previtamin derivative. Thermal isomerization, hydrolysis and chromatography then furnished the desired analog, 1alpha-hydroxypregnacalciferol. The compound was tested in vivo for its effect on intestinal calcium transport, serum calcium and phosphate levels and bone calcification, and in vitro for its effect on bone resorption. When given to intact rats, either as a single dose or in repeated daily doses, the analog even at high dose levels, exhibited no biological activity. The compound stimulated bone resorption in vitro, but only at high concentrations. 相似文献
12.
The purpose of the present study was to test the hypothesis that rat prostate microsomes contain a single cytochrome P450 enzyme responsible for the conversion of 5 alpha-androstane-3 beta,17 beta-diol to a series of trihydroxylated products. The three major metabolites formed by in vitro incubation of 5 alpha-[3H]androstane-3 beta,17 beta-diol with rat prostate microsomes were apparently 5 alpha-androstane-3 beta,6 alpha,17 beta-triol, 5 alpha-androstane-3 beta,7 alpha,17 beta-triol, and 5 alpha-androstane-3 beta,7 beta,17 beta-triol, which were resolved and quantified by reverse-phase HPLC with a flow through radioactivity detector. The ratio of the three metabolites remained constant as a function of incubation time, microsomal protein concentration, ionic strength, and substrate concentration. The ratio of the three metabolites was dependent on pH, apparently because the hydroxylation of 5 alpha-androstane-3 beta,17 beta-diol shifted from the 6 alpha- to the 7 alpha-position with increasing pH (6.8-8.0). The V(max) values were 380, 160, and 60 pmol/mg microsomal protein/min for the rate of 6 alpha-, 7 alpha-, and 7 beta-hydroxylation, respectively. Similar Km values (0.5-0.7 microM) were measured for enzymatic formation of all three metabolites, which suggests that formation of all three metabolites was catalyzed by a single, high-affinity enzyme. Testosterone, 5 alpha-dihydrotestosterone, and 5 alpha-androstane-3 alpha,17 beta-diol did not appreciably inhibit the hydroxylation of 5 alpha-androstane-3 beta,17 beta-diol, suggesting that this enzyme exhibits a high degree of substrate specificity. Formation of all three metabolites was inhibited by antibody against rat liver NADPH-cytochrome P450 reductase (85%) and by a 9:1 mixture of carbon monoxide and oxygen (60%). Several chemical inhibitors of cytochrome P450 enzymes, especially the antimycotic drug clotrimazole, also inhibited the formation of all three metabolites. Polyclonal antibodies that recognize liver cytochrome P450 1A, 2A, 2B, 2C, and 3A enzymes did not inhibit 5 alpha-androstane-3 beta,17 beta-diol hydroxylase activity. Overall, these results are consistent with the hypothesis that the 6 alpha-, 7 alpha-, and 7 beta-hydroxylation of 5 alpha-androstane-3 beta,17 beta-diol by rat prostate microsomes is catalyzed by a single, high-affinity P450 enzyme. This cytochrome P450 enzyme appears to be structurally distinct from those in the 1A, 2A, 2B, 2C, and 3A gene families. 相似文献
13.
16alpha-Hydroxymethyl-5alpha-androstane-3beta,17beta-diol and 16beta-hydroxymethyl-5alpha-androstane-3beta,17beta-diol, were obtained from reduction of 16-acetoxymethylene-5alpha-androstan-17-one. The corresponding 16alpha,17alpha- and 16beta,17alpha-hydroxymethyl isomers were obtained by neighboring group participation of the 16- and 17-acetates, respectively. The reactions involving carbocation formation also led to ring D rearrangement products. 相似文献
14.
Rat ventral prostate and liver were investigated for the binding in vitro to particulate fractions and for the metabolism of 5 alpha-androstane-3 beta, 17 beta-diol. Comparative investigations were carried out on the metabolism of 5 alpha-androstane-3 alpha, 17 beta-diol. Preparations of the liver were investigated in order to establish the organ specificity of the method. In the prostate, the bulk of the metabolites of 5 alpha-androstane-3 beta, 17 beta-diol was present as steroids of high polarity. Of the less polar metabolites, 17 beta-hydroxy-5 alpha-androstan-3-one, 3 beta-hydroxy-5 alpha-androstan, 17-one and 5 alpha-androstane-3 alpha, 17 beta-diol were detectable. The binding of a 5 alpha-androstane-3 beta, 17 beta-diol to mitochondria and microsomes was unspecific. In the liver, among the less polar metabolites, 3 beta-hydroxy-5 alpha-androstan-17-one was the main metabolite, and the binding was unspecific. The main metabolite in the prostate homogenate of 5 alpha-androstane-3 alpha, 17 beta-diol was 17 beta-hydroxy-5 alpha-androstan-3-one. The portion of highly polar steroids was very low. The portion of unmetabolized hormone was distributed almost equally among the different cell preparations except the nuclei, in which 17 beta-hydroxy-5 alpha-androstan-3-one was higher and 5 alpha-androstane-3 alpha, 17 beta-diol was lower than in the remaining cell fractions. 相似文献
15.
E P Murono V Fisher-Simpson 《Biochemical and biophysical research communications》1984,121(2):558-565
The direct effect of ethanol on dihydrotestosterone (DHT) conversion to 5 alpha-androstan-3 beta,17 beta-diol (3 beta-diol) and 5 alpha-androstan-3 alpha,17 beta-diol (3 alpha-diol) by adult rat Leydig cells was examined. Concentrations of ethanol comparable to blood levels of alcoholic men (2.2 - 65 mM) increased DHT conversion to 3 beta - and 3 alpha-diol, in direct relation to the dose of ethanol added; a 2-fold or greater stimulation was observed. Because this effect was blocked by 4-methylpyrazole or a saturating NADH concentration, these results suggest that this action is mediated by Leydig cell alcohol dehydrogenase activity. These results may have significant impact in the testis and/or other DHT sensitive tissues because ethanol may decrease the availability of the proposed active androgen. 相似文献
16.
The molecular structures and absolute configurations of alpha- and beta-anordrins are reported. Pure alpha- and beta-epimers were obtained with recrystallization and column chromatography combined with high-pressure liquid chromatography methods; they were identified by high-resolution infrared and mass spectra and 1H and 13C nuclear magnetic resonance. By single crystal x-ray diffraction analysis, the crystals of alpha- and beta-epimers were found to belong to the orthorhombic space groups P2(1)2(1)2(1) and P2(1)2(1)2, respectively. The molecular structures of these two epimers were determined. The absolute configurations were deduced by conformation analysis, 1H nuclear magnetic resonance, and comparison with the absolute configuration of the starting material. The absolute configurations of asymmetric centers of alpha- and beta-epimers were observed to be 2R, 5S, 8R, 9S, 10S, 13S, 14S, 17R, and 2S, 5S, 8R, 9S, 10S, 13S, 14S, 17R, respectively. These results were confirmed by the x-ray diffraction determination of the absolute configuration of 2 alpha,17 alpha-diethynyl-A-nor-5 alpha- androstane-2 beta, 17 beta-diol dichloroacetate. 相似文献
17.
Significant metabolism of 5 alpha-androstane-3 beta,17 beta-diol to 17 beta-hydroxy-5 alpha-androstan-3-one was recorded in several tissues and organs from rats and humans. This bioconversion was further investigated in rat testis homogenates. 5 alpha-Androstane-3 beta,17 beta-diol was readily metabolized to 17 beta-hydroxy-5 alpha-androstan-3-one with NAD and/or NADP added as cofactors. When a NADPH generating system was included in the incubation, 5 alpha-androstane-3 beta,17 beta-diol was metabolized to 5 alpha-androstan-3 alpha,17 beta-diol. Only small amounts of 17 beta-hydroxy-5 alpha-androstan-3-one accumulated under the latter condition. 相似文献
18.
Further studies on the inhibition of sterol biosynthesis in animal cells by 15-oxygenated sterols 总被引:1,自引:0,他引:1
The chemical syntheses of a number of C27 15-oxygenated sterols and their derivatives have been pursued to permit evaluation of their activity in the inhibition of sterol biosynthesis in animal cells in culture. Described herein are chemical syntheses of 3 alpha-benzoyloxy-5 alpha-cholest-8(14)-en-15-one, 5 alpha-cholest-8(14)-en-3 alpha-ol-15-one, 5 alpha-cholest-8(14)-en-15-one-3 beta-yl pyridinium sulfate, 5 alpha-cholest-8(14)-en-15-one-3 beta-yl potassium sulfate (monohydrate), 5 alpha-cholest-8(14)-en-15-one-3 alpha-yl pyridinium sulfate, 5 alpha-cholest-8(14)-en-3 alpha-yl potassium sulfate (monohydrate), 5 alpha-cholest-8(14)-en3,7,15-trione, 5 alpha-cholest-8(14)-en-15 alpha-ol-3-one, 5 alpha, 14 alpha-cholestan-3 beta, 15 beta-diol diacetate, 5 alpha, 14 beta-cholestan-3 beta, 15 beta-diol diacetate, 5 alpha, 14 alpha-cholestan-3 beta, 15 alpha-diol, 5 alpha, 14 alpha-cholestan-15 alpha-ol-3-one, 5 alpha, 14 beta-cholestan-3 beta, 15 beta-diol, 5 alpha, 14 alpha-cholestan-3,15-dione, and 5 alpha, 14 beta-cholestan-3,5-dione. The effects of 8 of the above compounds and of 5 alpha-cholesta-6,8(14)-dien-3 beta-ol-15-one, 3 beta-he misuccinoyloxy-5 alpha-cholest-8(14)-en-15 one, 3 beta-hexadecanoyloxy-5 alpha-cholest-8(14)-en-15-one, 5 alpha-cholest-8(14)-en-3,15-dione, 5 alpha-cholesta-6,8(14)-dien-3,15-dione, 5 alpha-cholest-8-en-3 beta, 15 alpha-diol, 5 alpha-cholest-7-en-3 beta, 15 alpha-diol, 5 alpha-cholest-8(14)-en-15 alpha-ol-3-one, 5 alpha-cholest-8-en-15 alpha-ol-3-one, and 5 alpha-cholest-7-en-15 alpha-ol-3-one on the synthesis of digitonin-precipitable sterols and on levels of HMG-CoA reductase activity have been investigated and compared with previously published data on 7 other C27 15-oxygenated sterols. 相似文献
19.
The effect of attachment of a dimethylaminoethoxy or a dimethylaminopropoxy group at the 11 beta-position of estradiol (E2) on its relative binding affinity (RBA) to estrogen receptor (ER) and intrinsic biologic activity is described. The binding of 11 beta-[2-(N,N-dimethylamino) ethoxy]estra-1,3,5(10)-triene-3,17 beta-diol (4) and 11 beta-[3-(N,N- dimethylamino)propoxy]estra-1,3,5(10)-triene-3,17 beta-diol (5) to the ER from immature rat uterine tissue was measured relative to that of [3H]E2 by a competitive binding assay. It was found that the 11 beta-substituted E2 analogs have considerably lower RBA to ER than the corresponding parent compound. The intrinsic activity of compounds 4 and 5 were studied in terms of uterotrophic and antiuterotrophic activity. It was found that the uterotrophic activity of these compounds was drastically reduced compared with E2. However, no antiuterotrophic activity was observed in these compounds at dosages ranging from 1 to 100 micrograms/rat/d. 相似文献
20.
The present results demonstrate for the first time in rat liver, that low ethanol concentrations (2.2 and 22 mM) directly stimulate dihydrotestosterone conversion to 5 alpha-androstan-3 alpha, 17 beta-diol and 5 alpha-androstan-3 beta, 17 beta-diol. Because this effect was blocked by 4-methylpyrazole, an alcohol dehydrogenase inhibitor, or by the addition of a saturating NADH concentration, this action probably is mediated by hepatic alcohol dehydrogenase activity through elevation of the NADH/NAD+ ratio. It remains to be determined whether this effect of ethanol actually reduces circulating and/or target tissue dihydrotestosterone levels; nevertheless, it is tempting to speculate that this action, in part, is responsible for the reported adverse effects of alcohol on male reproductive functions. 相似文献