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1.
When androstenedione was incubated with testicular microsomes of Sprague-Dawley rats in the presence of reduced nicotinamide-adenine dinucleotide (NADH), unknown metabolites were produced, in addition to testosterone and 7 alpha-hydroxyandrostenedione. The metabolites were identified as 3 beta-hydroxy-4-androsten-17-one and 3 beta-hydroxy-5-androsten-17-one (3:1) by biochemical and radiochemical methods. These results confirmed the occurrence of the reverse reactions from androstenedione to 3 beta-hydroxy-4-androsten-17-one and 3 beta-hydroxy-5-androsten-17-one catalyzed by the 3 beta-hydroxysteroid dehydrogenase and 5-ene-4-ene isomerase in the microsomal fraction of Sprague-Dawley rat testes. 相似文献
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13beta-Ethyl-3-methoxy-17beta-ol-8,14-seco-1,3,5(10),8-gonatetraen-14-one (IIIa) was isolated and its participation in the well-known acidic cyclization process was established. 相似文献
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From the structure activity relationship, two new analogs, 2 and 3, of the potent progesterone antagonist mifepristone 1 have been designed. The syntheses of these two analogs have been achieved in eleven steps through modified synthetic sequences and improved procedures starting from (+)-estrone. In comparison with mifepristone 1, the relative binding affinities of compound 2 for the progesterone receptor was found to be more, whereas that of compound 3 was less. 相似文献
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3 beta,16 alpha,19-Trihydroxy-5-androsten-17-one and 16 alpha,17-dihydroxy-4-androstene-3,17-dione were synthesized from the 5 alpha-bromo-6 beta,19-epoxy-17-ketone derivative 1, using the bromination at C-16 alpha of the 17-ketone 1 and the controlled alkaline hydrolysis of the 16 alpha-bromo-17-ketones 2 and 11 as key reactions. Zinc dust reductive cleavage of the 6 beta,19-epoxy-16 alpha-hydroxy-17-ketones 4 and 12, produced by controlled hydrolysis, gave the corresponding 19-alcohol derivatives 6 and 14, which were rearranged to the 17 beta-hydroxy-16-ketones 7 and 15 when treated with sodium hydroxide. The 3 beta,16 alpha,17 beta,19-tetrol 8 was obtained from the 16 alpha-ketol 6 by reaction with sodium borohydride. 相似文献
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Federica Compostella Diego Colombo Emilia Modica Lucio Antonio ScalaToma Bruna Bovio Fiamma Ronchetti 《Steroids》2002,67(2):111-117
The structure of 13-ethyl-11-methylene-18,19-dinor-17alpha-pregn-4-en-20-yn-16beta,17-diol (3, 16beta-OH desogestrel), a by-product obtained in the last step of the synthesis of desogestrel (1) by reaction of monolithium acetylide-ethylenediamine complex with 13beta-ethyl-11-methylenegon-4-en-17-one (2), is here reported. The structural assignments were supported by NMR 1H-, 13C-, 1H-1H COSY, 1H-13C HSQC, COLOC) and mass spectroscopy, and the configuration at the C-16 and C-17 stereocentres was established by X-ray crystallography. When the same 17-ketoderivative 2 was treated with a non-alkylating base, such as potassium tert-butoxide, instead of the expected 16-hydroxylated ketone, a dimeric product, 13beta-ethyl-16-[2'-(des-D-13"-carboxy-13"beta-ethyl-11"-methylenegon-4"-en-14"-yl)-ethyliden]-11-methylenegon-4-en-17-one (4), was isolated in good yield; it was characterized by NMR, mass, ultraviolet spectroscopy, and chemical transformations. Compounds 3 and 4 originate from the high reactivity of the 16-methylenic position of the 17-keto substrate (2) toward molecular oxygen under basic conditions. 相似文献
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W Ferrari A Bertolini P Mucci E Sternieri 《Bollettino della Società italiana di biologia sperimentale》1968,44(16):1310-1313
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Extracts of squirrel plasma have been chromatographed on partition columns (using a hydrophilic stationary phase) at atmospheric pressure (Celite support) and a reversed phase system at high pressure (HPLC). Both methods effectively separated testosterone, 17 beta-hydroxy-5 alpha-androstan-3-one (DHT) and 4-androstene-3,17-dione; they gave elution patterns that differed considerably. Chromatographic mobility of the three androgens on the two systems was identical with that of fractions of squirrel plasma extracts that gave responses measured by appropriate androgen radioimmunoassays; good evidence for the occurrence of these androgens in squirrel plasma is thus provided. Plasma testosterone levels were 300 pmol/l in juvenile males, 800-7000 pmol/l in sexually-active males but undetectable (less than 50 pmol/l) in sexually-regressed males. Plasma DHT levels were also high in sexually-active males, but undetectable in other males except for one regressed individual. Plasma androstenedione was higher in juvenile males than in adult males, in which it was similar whether or not they were sexually regressed. Plasma testosterone and DHT, unlike androstenedione, were totally dependent on the presence of the testes. In females testosterone and DHT were undetectable in plasma but androstenedione levels were high, especially at oestrus. Androstenedione was dependent on the presence of the ovaries. 相似文献
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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
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Synthetic routes leading to 19E and 7Z O-(carboxymethyl)oximes derived from 16alpha-hydroxydehydroepiandrosterone were developed using two independent methods for introduction of the 16alpha-hydroxy group. Firstly, the oxime moiety was built, and then, either epoxidation of the enol acetate followed by the boron trifluoride mediated rearrangement or alkaline hydrolysis of the corresponding alpha-bromide in aqueous N,N-dimethylformamide were employed. The last step in both methods was removal of the protecting groups, which consisted of acid deprotection of the acetates and gentle alkaline hydrolysis of the methyl ester. Final haptens were designed as components for immunoanalytical kits. 相似文献
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The urinary excretion of 3beta,16beta-dihydroxy-5-androsten-17-one (16beta-OH-DHEA) is increased in patients with low renin essential hypertension. This steroid and its isomer 3beta,17beta-dihydroxy-5-androsten-16-one (16-oxo-A) have also been reported to have mineralocorticoid activity in adrenalectomized rats. These findings have led to the postulate that excessive secretion of 16beta-OH-DHEA may be responsible for the production of low renin essential hypertension. In this study unilaterally nephrectomized salt loaded rats injected once a week with 30 mg of 11-desoxycorticosterone acetate per/kg of body weight for 2 month periods developed hypertension. Rats given similar amounts of 16beta-OH-DHEA or 16-oxo-A and rats given no steroids did not develop hypertension. We conclude that it is unlikely that 16beta-OH-DHEA and 16-oxo-A are direct causative factors in the production of low renin essential hypertension. 相似文献
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J R Pasqualini R Castellet M C Portois J L Hill F A Kincl J Cortes-Prieto 《Reproducción》1975,2(3-4):197-205
The experiment conditions for the evaluation of Norethindrone (17 alpha-Ethynyl-17 beta-hydroxy-4-estren-3-one, NET) and Ethynyl-estradiol (17 alpha-ethynyl-1, 3, 5 (10) estratrien-3, 17 beta-diol, EE) by radioimmunoassay are described. A minimal quantity of 25 pg of these two steroids could be evaluated using different reduced metabolites of NET, very little cross reaction is observed with 200 pg of these metabolites. No effect was observed with estradiol for the EE-antiserum. The NET-antiserum was used to evaluate this steroid and ethynodiol diacetate after oral administration to female volunteers. Maximal values in the plasma (2-3% of the administered dose) was found between 1-3 h after administration and at 24 h a concentration of 0.1-0.3% still remained in the plasma. 相似文献
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W Ferrari A Bertolini P Mucci E Sternieri 《Bollettino della Società italiana di biologia sperimentale》1968,44(16):1309-1310
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This study investigates the efficiency of BOMT as an androgen antagonist within the central nervous system. The efficiency of BOMT in suppressing neural receptor binding of testosterone, and the ability of this antiandrogen to block the feedback loop of testosterone onto the central nervous system, as evidenced by plasma testosterone levels, is reported. BOMT was found to be unable to open the feedback loop of testosterone onto the central nervous system, which was correlated with the low competing efficiency of this antiandrogen for receptor sites in vitro within the hypothalamic-preoptic area of the brain - a region known to be involved in gonadotrophin secretion. The observed divergence in the degree of antiandrogenicity of BOMT between peripheral and central target tissues of testosterone is discussed. 相似文献
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An efficient one-pot procedure for the preparation of 10beta,17beta-dihydroxyestra-1,4-dien-3-one (p-quinol, 1, 75%) is reported, involving oxidation of 17beta-estradiol with potassium permanganate. Similar treatment of 17beta-estradiol with sodium chlorite led to 10beta-chloro-17beta-hydroxyestra-1,4-dien-3-one (2) in 44% yield along with smaller amounts 4-chloro-10beta,17beta-dihydroxyestra-1,4-dien-3-one (3), 2,10beta-dichloro-17beta-hydroxyestra-1,4-dien-3-one (4), and 4,10beta-dichloro-17beta-hydroxyestra-1,4-dien-3-one (5). 相似文献
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The effects of a new synthetic steroid, 17 beta-hydroxy-11 beta-4-dimethyl-aminophenyl-17 alpha-propynyl-estra-4,9-dien-3-one, classified under reference R38486 in the Roussel-Uclaf nomenclature [1], were investigated in two established rat hepatoma cell lines in order to gain information on the mechanism of action. The induction of tyrosine aminotransferase (TAT) and alanine aminotransferase (AAT) was totally abolished when R38486 was added with dexamethasone either on a 1-1 basis or on a 10-fold excess depending on the differentiation state of the cell. Binding studies showed a high affinity for the glucocorticoid receptor; however our "whole cell" study with [3H] R38486 indicates that only a low amount of antagonist-receptor complexes was translocated into the nucleus. Nuclear fractionation experiments showed that R38486, like the other antagonists studied, was located in the chromatin fraction where it may exert some definite role. Our observations based on whole cell experiments using physiological doses of glucocorticoid analogs indicate that the binding of activated antiglucocorticoid-receptor complexes to nuclear acceptor sites represents a physiologically significant process. Moreover the differences in the nuclear binding of antagonist-receptor- as compared to agonist-receptor-complexes may set off the machinery of antagonistic action. 相似文献