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1.
The in vivo and in vitro antiandrogenic activity of four new progesterone derivatives: 4-bromo-17alpha-(p-fluorobenzoyloxy)-4-pregnene-3,20-dione 1,4-bromo-17alpha-(pchlorobenzoyloxy)-4-pregnene-3,20-dione 2, 4-bromo-17alpha-(p-bromobenzoyloxy)-4-pregnene-3,20-dione 3 and 4-bromo-17alpha-(p-toluoyloxy)-4-pregnene-3, 20-dione 4 was determined. These compounds were evaluated as antiandrogens on gonadectomized hamster prostate and reduced the weight of the prostate glands in gonadectomized hamsters treated with testosterone 5 (T) or dihydrotestosterone 6 (DHT) in a similar manner to that of commercially available finasteride, thus indicating a potent in vivo effect. The in vitro studies showed that steroids 1-4 have a weak inhibitory activity on 5alpha-reductase with IC50 values of: 280 (1), 2.6 (2), 1.6 (3) and 114 microM (4). The presence of Cl and Br atoms in the C-17 benzoyloxy group tends to increase the inhibitory potency of the compounds. The binding efficiency of the synthesized steroids 1-4 to the androgen receptor of the prostate gland is also evaluated. All compounds form a complex with the receptor and this explains the weight reduction of the seminal vesicles in the animals treated with DHT plus steroids 1-4.  相似文献   

2.
A method for the convenient synthesis of the recently isolated allylic gonadal steroids, 3 alpha-hydroxy-4-pregnen-20-one (3 alpha-dihydroprogesterone; 3 alpha-DHP) and 3 alpha-hydroxy-4-androsten-17-one (3 alpha-HA), was developed using 4-pregnene-3,20-dione (progesterone) and 4-androstene-3,17-dione as substrates and potassium trisiamylborohydride (KS-Selectride) as reducing agent. Similar reactions were also used for the reduction of 5 alpha-pregnane-3,20-dione to 3 alpha-hydroxy-5 alpha-pregnan-20-one (3 alpha-HP). The yields were about 15%, 50%, and greater than 90% for 3 alpha-DHP, 3 alpha-HA and 3 alpha-HP, respectively. Structures of the products, including the 3 beta-isomers and the 17 alpha-epimer, formed in these reactions were determined by NMR and mass spectroscopic methods.  相似文献   

3.
A total of fifty steroidal compounds were tested for their inhibition on the binding of muscarinic receptor antagonist, [3H]quinuclidinyl benzilate ([3H](-)QNB), to the hypothalamic membranes prepared from male rats. Among the compounds tested, the active structures (with IC50 values less than or equal to 100 microM in parentheses) are: progesterone (40), 5 beta-pregnane-3,20-dione (40), deoxy-corticosterone (50), 5 beta-pregnane-17 alpha,21-diol-3,20-dione (30), 11-desoxy-17-hydroxycorticosterone (22), 17 alpha-hydroxyprogesterone (20), 5 beta-pregnan-17 alpha-ol-3,20-dione (24), 5 beta-androstane-3,17-dione (100), and 5 beta-dihydrotestosterone (100). By examining all the compounds tested, the following structure-activity relationship became apparent: (a) The ring A-reduced steroidal structures with a 5 beta-conformation were more potent than those with a 5 alpha-conformation; (b) 17 alpha-hydroxylation of the steroidal ring increased the steroid's inhibitory activity; (c) The C3 carbonyl group was essential for activity; (d) Reduction of the C3 carbonyl group or aromatization of the ring A abolished the steroid's inhibitory activity; (e) Oxidation of the C11 position of ring C resulted in a decrease or loss of inhibitory activity; and (f) Different modifications of the side chain of ring D by acetylation resulted in either an increase or a decrease in the inhibitory activity. The structure-activity relationship as revealed in this study might provide an insight for the synthesis of a steroidal molecule with a high affinity for the muscarinic receptor as well as for the search of a more potent and physiologically relevant steroidal metabolite possessing the ability to interact with the muscarinic receptor.  相似文献   

4.
The aim of this study was to ascertain the inhibitory effect of several progesterone derivatives for 5α-reductase types 1 and 2 isozymes and to determine the binding to the androgen receptor.The 3,20-dioxopregna-4-ene-17α-yl acetate 4 containing an acetoxy group in C-17 and steroid 17α-hydroxypregn-4-ene-3,20-dione 5 having a hydroxyl group in the same position inhibited both isozymes. On the other hand, 17α-hydroxy-4,5-epoxypregnan-3,20-dione 6 with an epoxy function at C-4, inhibited only the type 1 enzyme. Steroid 4-chloro-17α-hydroxypregn-4-ene-3,20-dione 7a and 4-bromo-17α-hydroxypregn-4-ene-3,20-dione 7b having the C-4 conjugated system and a chlorine or a bromine atom at C-4 respectively, inhibited both types of 5α-reductase. These results indicate that an increase in the electronegativity of ring A produces a major inhibitory activity for 5α-reductase type 1; however this increase was not observed for type 2 enzyme. When the free hydroxyl group of 7a or 7b was esterified, compounds 3,20-dioxo-4-chloropregn-4-ene-17α yl-4-ethylbenzoate 8a and 3,20-dioxo-4-bromopregn-4-ene-17α yl-4-ethylbenzoate 8b were obtained; these steroids inhibited only the 5α-reductase type 2 enzyme.Finasteride and steroids 4, 5, 7b, 8a showed a comparable in vivo pharmacological activity, however the IC50 values of these compounds were higher as compared to that of finasteride.These results indicated also that steroids 4, 5, 7a, and 7b bind to the androgen receptor whereas compounds 6, 8a and 8b failed to do so.The overall data from this study showed that steroids 5 and 7b bind to the AR and decreased of the growth of prostate and seminal vesicles. Moreover, 4 decreased also the growth of seminal vesicles.  相似文献   

5.
A blinded cooperative assay of several androstane and pregnane steroid metabolites has been carried out in order to determine whether 5β-H derivatives are as active as testosterone in stimulating in vivo erythropoiesis. The steroids tested were: testosterone, 5-dihvdrotestosterone, 5β-dihydrotestosterone, 5β-pregnane-3,20-dione, 3-dihydroxy-5β-pregnàne-11,20-dione and 3β-hydroxy-5β-pregnan-20-one. The incorporation of radioactive iron into newly formed red cells in exhypoxic polycythemic mice was used to compare the effects of the steroids. Testosterone and 5-dihydrotestosterone both produced significant increases in 59Fe incorporation. 5β-dihydrotestosterone, 5β-pregnane-3,20-dione, 3-hydroxy-5β-pregnane-11,20-dione and 3β-hydroxy-5β-pregnan-20-one were all devoid of significant erythropoietic activity in polycythemic mice in almost all instances. Thus, under the conditions chosen, this study failed to demonstrate that 5β-steroids increase radioactive iron incorporation in red cells of exhypoxic polycythemic mice.  相似文献   

6.
The in vivo and in vitro antiandrogenic activity of four new progesterone derivatives: 4-bromo-17α-(p-fluorobenzoyloxy)-4-pregnene-3,20-dione 1,4-bromo-17α-(p-chlorobenzoyloxy)-4-pregnene-3,20-dione 2, 4-bromo-17α-(p-bromobenzoyloxy)-4-pregnene-3,20-dione 3 and 4-bromo-17α-(p-toluoyloxy)-4-pregnene-3, 20-dione 4 was determined. These compounds were evaluated as antiandrogens on gonadectomized hamster prostate and reduced the weight of the prostate glands in gonadectomized hamsters treated with testosterone 5 (T) or dihydrotestosterone 6 (DHT) in a similar manner to that of commercially available finasteride, thus indicating a potent in vivo effect. The in vitro studies showed that steroids 14 have a weak inhibitory activity on 5α-reductase with IC50 values of: 280 (1), 2.6 (2), 1.6 (3) and 114?μM (4). The presence of Cl and Br atoms in the C-17 benzoyloxy group tends to increase the inhibitory potency of the compounds.

The binding efficiency of the synthesized steroids 14 to the androgen receptor of the prostate gland is also evaluated. All compounds form a complex with the receptor and this explains the weight reduction of the seminal vesicles in the animals treated with DHT plus steroids 14.  相似文献   

7.
中国南海侧扁软柳珊瑚中孕甾烷类化学成分的研究(英文)   总被引:1,自引:0,他引:1  
从南海侧扁软柳珊瑚Subergorgia suberosa的二氯甲烷-甲醇提取物中首次分离鉴定了8个孕甾烷类化合物,经波谱鉴定为3β-O-palmitoyl-pregn-5-ene-20-one-3-ol (1),3β-O-palmitoyl-5α-pregn-20-one-3-ol (2),5α-pregn-1-ene-3,20-dione (3),3β,5α-pregn-20-one-3-ol (4),3β-pregn-5-ene-20-one-3-ol (5),3β,5β-pregn-20-one-3-ol (6),5β-pregn-3,20-dione (7),pregn-4-ene-3,20-dione (8).其中化合物1,2为新化合物.  相似文献   

8.
3beta-Hydroxypregn-5-en-20-one (pregnenolone) and NAD+ were incubated with a solubilized preparation of the coupled enzyme 3beta-hydroxysteroid:NAD(P) oxidoreductase-3-ketosteroid delta4,delta5-isomerase (3beta-hydroxysteroid dehydrogenase: delta5-isomerase) from the mitochondrial fraction of human placenta. Unconverted pregnenolone, pregn-4-ene-3,20-dione (rogesterone), and a small but detectable amount of pregn-5-ene-3,20-dione were isolated from the medium by Sephadex LH-20 chromomatography. The identification of pregn-5-ene-3,20-dione, confirmed by mass fragmentography, has provided the first direct evidence for the formation of the hypothetical delta5,3-ketone intermediate in the conversion of pregnenolone to progesterone. When tritium-labeled pregnenolone and [4-14C]pregnenolone were incubated simultaneously the 3H:14C ratio in isolated pregn-5-ene-3,20-dione was 4.6 times greater than in isolated progesterone and pregnenolone, indicating a kinetic isotope effect in the enzymatic isomerization of tritium-labeled pregn-5-ene-3,20-dione. Exposure of the enzyme to two steroids which inhibit the overall enzyme reaction, 2alpha-cyano-17beta-hydroxy-4,4,17alpha-trimethylandrost-5-en-3-one (cyanoketone) and 3-hydroxyestra-1,3,5(10),6,8-pentaen-17-one (equilenin), increased the relative yield of labeled pregn-5-ene-3,20-dione as well as the recovery of radioactivity remaining as unconverted pregnenolone, suggesting that both the dehydrogenase and isomerase activities were inhibited. Exposure of the enzyme to equilenin increased the ratio of isolated pregn-5-ene-3,20-dione radioactivity to progesterone radioactivity as progesterone synthesis was inhibited. Equilenin also diminished the tritium isotope effect on the isomerase reaction. Both findings suggest that it is possible to inhibit the isomerase to a greater extent than the dehydrogenase. In order to measure the rate of progesterone produced by the coupled enzymes, we have modified a radiochemical method which involves precipitation of pregnenolone by digitonin. Digitonin precipitation proved to be effective in separating unconverted pregnenolone from the steroid products of both enzyme reactions, progesterone and pregn-5-ene-3,20-dione. Neither the steroidal inhibitors nor the kinetic isotope effect altered the accuracy of the method for routine measurement of the overall rate of conversion of delta5,3beta-hydroxysteroid to delta4,3-ketosteroid.  相似文献   

9.
The microbiological reduction of the 20-carbonyl group of steroids has been investigated. Candida pulcherrima IFO 0964 and Sporotrichum gougeroti IFO 5982 converted the following substrates into the corresponding 20β-hydroxy derivatives (yields of the products are indicated in parentheses): Reichstein’s Compound S (60~70%) and 17α,21-dihydroxypregna-l,4-diene- 3,20-dione (40~80%). Rhodotorula glutinis IFO 0395 converted the following substrates into the corresponding 20α-hydroxy derivatives: Reichstein’s Compound S (65%), 17 α,21-dihydroxy- pregna-l,4-diene-3,20-dione (80%), llβ,l7α-dihydroxypregn-4-ene-3,20-dione (45%) and 17α, 19,21 -trihydroxypregn-4-ene-3,20-dione (10%).  相似文献   

10.
Sertoli cells isolated from 17 day old rats were maintained in culture and incubated with [14C]-progesterone for 20 h. The cells and media were extracted with ether/chloroform and the extracts chromatographed two-dimensionally on TLC and the radioactive metabolites visualized by autoradiography. Nine of the metabolites (constituting about 88% of total metabolite radioactivity) were identified by relative mobilities of the compounds and their derivatives in TLC and GC systems and by recrystallizations with authentic steroids as the following: 20α-hydroxypregn-4-en-3-one, 3α-hydroxy-5α-pregnan-20-one, 5α-pregnane3α,20α-diol, 17β-hydroxy-5α-androstan-3-one, 5α-pregnane-3,20-dione, 17-hydroxypregn-4-ene-3,20-dione, testosterone, 5α-androstane-3α,17β-diol and androst-4-ene-3,17-dione. Over 71% of the metabolite radioactivity was due to 20α-hydroxypregn-4-en-3-one, the major metabolite. 5α-reduced pregnanes constituted about 12% and C19 steroids comprised about 2.9% of the radioactivity of the metabolites. Calculation of relative steroidogenic enzyme activities from initial reaction rates suggested the following activities in μunits/mg Sertoli cell protein: 20α-hydroxysteroid oxidoreductase (20α-HS0; 7.71), 5α-reductase (4.77), 3α-HS0 (3.57), 17α-hydroxylase (0.93), 17β-HS0 (0.34) and C17-C20 lyase (0.34). The relatively high rate of steroidogenic enzyme activities in the Sertoli cells of young rats may indicate that Sertoli cells are less dependent on Leydig cell steroidogenesis than has been assumed. Since nearly all the metabolites of progesterone and testosterone are now identified, it is possible to construct a picture of Sertoli cell steroidogenic activity.  相似文献   

11.
3 alpha-Hydroxy-17-acetoxy-6 alpha-methyl-5 beta-pregnan-20-one (IIIa) has been isolated from urine of patients receiving medroxyprogesterone acetate (MPA). It was characterized by partial synthesis from MPA by catalytic reduction with palladium-charcoal to 17-acetoxy-6 alpha-methyl-5 beta-pregnan-3,20-dione (IV) and reduction of the latter with sodium borohydride. The isolation of 6 beta, 17,21-trihydroxy-6 alpha-methyl-pregn-4-ene-3,20-dione (IIc) is reported for the first time. The 17- and 21-monoacetates of this compound have been isolated and characterized earlier by other investigators. 7 alpha-3H-Medroxyprogesterone acetate was administered to 4 subjects by intravenous and intramuscular injections and by mouth. The ring A saturated metabolite IIIa was excreted in 0.1% to 4.0% of the administered dose; the highest excretion was after the intravenous dose and lowest after oral ingestion. 6 beta, 17,21-Trihydroxy-6 alpha-methylpregn-4-ene-3,20-dione (IIc) and its 17- and 21-monoacetates were excreted in about 5% of the doses in all subjects. No increase in 6 beta-hydroxylation was observed in the patient treated with o,p'-DDD,2,2-bis(2-chlorophenyl, 4'-chlorophenyl)-l,1-dichloroethane.  相似文献   

12.
In pregnant rock hyraxes isolated leucocytes metabolise both [3H]pregnenolone and [3H]progesterone while whole blood, erythrocytes and an erythrocyte/leucocyte mixture only metabolised [3H]progesterone. Plasma displayed no tendency to metabolically convert any one of these two steroids. In whole blood [3H]progesterone appears to be converted to 5alpha-pregnane-3,20-dione and a compound with chromatographic properties similar to that of 5alpha-pregnan-3alpha-ol-20-one. 5Alpha-pregnane-3,20-dione exhibited a high relative binding affinity for the uterine progesterone eceptor (94%), but 5alpha-pregnan-3alpha-ol-20-one displayed very little affinity for the same receptor (0.4%). 5Alpha-pregnane-3,20-dione may therefore aid in the maintenance of pregnancy. Corpora lutea metabolised progesterone to 17alpha-hydroxyprogesterone, a compound exhibiting no progestational function because of its low relative binding affinity for the uterine progesterone receptor (2%). Progesterone appears to be the main product of the corpus luteum. However, 5alpha-pregnane-3,20-dione circulated at concentrations approximately 8.5 times higher than progesterone, probably due to the metabolic conversion of progesterone to 5alpha-pregnane-3,20-dione by the blood. We conclude that in the hyrax progesterone, produced by the corpora lutea, enters the circulation, where it is reduced to 5alpha-pregnanes. 5Alpha-pregane-3,20-dione may then be transported to the uterus where it binds to the progesterone receptor to assist in the maintenance of pregnancy. This mechanism appears to be analogous to that of the African elephant which is phylogenetically related to the hyrax, except that in the elephant the 5alpha-reduced metabolites are produced by luteal tissue and not the blood.  相似文献   

13.
Several new 4,19-substituted steroids and previously synthesized corticosteroids were assayed for affinity to type 1 receptors in human mononuclear leukocytes. 11 beta,19-epoxy-4,21-dihydroxypregn-4-ene-3,20-dione (2) was hydrogenated with Pd-C to yield a mixture of all four dihydro derivatives 5, accompanied by 4,21-diacetoxy-11 beta,19-epoxy-3-hydroxypregnan-20-one (6) and 21-acetoxy-11 beta,19-epoxy-4-hydroxypregnane-3,20-dione (7). With hot acetic + p-toluenesulfonic acid 5 underwent rearrangement to 21-acetoxy-11 beta,19-epoxypregn-5-ene-4,20-dione (8) Pd-C hydrogenation of 3,21-diacetoxy-5 beta,19-cyclopregna-2,9(11)-diene-4,20-dione (10) gave 3,21-diacetoxy-5 beta,19-cyclopregn-5-ene-4,20-dione (11) and the 9,11-dihydro derivative of the latter. Treatment of 10 with warm HCl furnished 19-chloro-4,21-dihydroxypregna-4,9(11)-diene-3,20-dione (13). Pd-C hydrogenation of its diacetate 14 afforded the 4,5-dihydro derivative 18, 19-chloro-21-acetoxypregn-9(11)-en-20-one (15), its 4-acetoxy derivative 16 and the 3,4-diacetoxy derivative 17. When tested in a radioreceptor assay in human mononuclear leukocytes the synthesized compounds showed only low relative binding affinities (RBA) to type 1 receptor, the highest being 0.72% for 13 (aldosterone = 100%). For comparison, other RBA in this system were: 19-noraldosterone, 20%; 18-deoxyaldosterone, 5.8%; 18-deoxy-19-noraldosterone, 4.7%; 18,21-anhydroaldosterone, 0.37%; 17-isoaldosterone, 7.6% and apoaldosterone, 4.3%  相似文献   

14.
R A Auel  R W Freerksen  D S Watt 《Steroids》1978,31(3):367-374
In order to test the potential biological activity of 18-substituted progesterones, 3,20-dioxo-4-pregene-18-carbonitrile (ld approximately) was converted to 3,20-dioxo-4-pregnene-18-carboxylic acid (lb approximately) and methyl 3,20-dioxo-4-pregnene-18-carboxylate (ld approximately) via a sequence of reactions involving an intramolecular hydrolysis of the 18--arbonitrile. Lithium aluminum hydride reduction of the bisethylene ketal derived from la approximately furnished 18-aminomethyl-5-pregnene-3,20-dione 3,20-bisethylene ketal (8 approximately). Acetylation and hydrolysis furnished 18-acetamidomethyl-4-pregnene-3,20-dione (lf approximately) and simple hydrolysis of 8 approximately furnished 3'alpha H-5' 6'-dihydro-2',19 beta-dimethyl-3-oxo-4-goneno [13,17-c]pyridine (9 approximately). None of the compounds exhibited any activity in Clauberg or anti-Clauberg tests.  相似文献   

15.
Mimosine, a plant amino acid which is toxic in mammals, was shown to be a potent inhibitor of incorporation of [3H]thymidine in mouse bone marrow cells in liquid culture (is greater than 70% inhibition at a concentration of 2 x 10(-4) M). To determine the parts of the molecule responsible for the inhibitory mechanism the effects of 13 chemically related compounds were examined in this system. The structural features necessary for inhibitory activity of the 4(1H)-pyridones were (1) the 3-hydroxyl-4-oxo function of the pyridone ring together with (2) an alpha-alanine or a 2-aminoethyl side chain. Compounds based on several other hydroxy heterocyclic functions were either weakly active or inactive. 3-Hydroxy-4(1H)-pyridone, the goitrogen to which mimosine is converted in ruminants, was only slightly inhibitory. These results are compared with published information on the effects of some of these compounds on other types of mammalian cells in vitro. The mouse bone marrow system in which inhibition of incorporation of [3H]thymidine is used as an index of cytotoxicity was shown to be sensitive and reproducible, and could be useful for structure-activity investigations of other cytotoxic compounds.  相似文献   

16.
Either [3H] progesterone (0.5 or 5 nmol/5 muCi), 5alpha-[3H] pregnane-3,20-dione (5 nmol/5 muCi) or [14C] progesterone (6.6 nmol/0.2 muCi) plus 5alpha-[3H]-pregnane-3,20-dione (1 or 6.6 nmol/0.6 muCi), suspended in 0.05 ml of physiological saline solution, was injected into each testis of 32- and 90-day-old rats. Following injection, radioactive metabolites in testis and spermatic vein blood were extracted, isolated, measured and identified by column and paper chromatographies, with derivative formation and recrystallization to constant specific activity. In the blood and testis of older prepubertal rats, major 17-OH-C21 and C19 metabolites of progesterone were 5alpha-reduced steroids such as 3alpha, 17alpha-dihydroxy-5alpha-pregnan-20-one, 5alpha-androstane-3alpha,17beta-diol and androsterone. Following injection of [14C] progesterone plus 5alpha-[3H] pregnane-3,20-dione into 32-day-old rat testis, no significant augmentation of the isotope from progesterone was observed in 5alpha-reduced C19 steroids as compared with 5alpha-reduced 17-OH-C21 steroids, indicating that 5alpha-reduced C19 steroids were mainly formed from 5alpha-reduced 17-OH-C21 steroids in older prepubertal testis. In the blood and testis of adult rats, small amounts of 5alpha-reduced metabolites were shown to be produced from progesterone, while active 17alpha-hydroxylation of 5alpha-pregnane-3,20-dione followed by C17-C20-lyase reaction was demonstrated. These findings seem to indicate that formation of 5alpha-reduced C19 steroids from progesterone by the 5alpha-reduced pathway is a major pathway of androgen biosynthesis in older prepubertal rat testis in vivo.  相似文献   

17.
3-Imine formation between primary amines and 3-oxo-4-ene-steroids, followed by hydrolysis of the imines (either spontaneously during work up or induced by acetic acid) has been shown to cause 6-oxygenation of the steroids tested (17 beta-hydroxy-4-androsten-3-one, 4-androstene-3,17-dione, 4-pregnene-3,20-dione and 4-cholesten-3-one). The main products are the 6 beta-hydroxy- and the 6-oxo-derivatives of the respective steroid. These derivatives were identified by chromatographic mobilities and by gas chromatography-mass spectrometry. The formation of 6 beta-hydroperoxy-derivatives is suggested and these derivatives were tentatively identified. The highest yields of 6-oxygenated products (30-50%) were found when cadaverine and spermine were reacted with the steroids. The addition of reduced glutathione during hydrolysis of the steroid 3-imines of cadaverine, hexylamine and ethanolamine as well as addition of ascorbic acid during the hydrolysis of the steroid 3-imines of cadaverine substantially reduced the 6-oxygenation. Steroid 3-imine formation and hydrolysis which yields 6-oxygenated derivatives has also been shown to occur during work up (evaporation) of organic solvent extracts of rat liver microsomes (105,000 g sediments) to which 17 beta-hydroxy-4-androsten-3-one, 4-androstene-3,17-dione, 4-pregnene-3,20-dione or 4-cholesten-3-one respectively had been added. It is concluded that there is a risk that these organic reactions are mistaken for enzymatic conversions during in vitro investigations of 3-oxo-4-ene-steroids.  相似文献   

18.
2 alpha-Hydroxyprogesterone (2 alpha-hydroxy-4-pregnene-3,20-dione) was identified in human late pregnancy urine by liquid-gel chromatography, GLC and GC-MS. In addition, the following 2-hydroxylated C21 steroids were found and identified as 2 zeta-hydroxy-5 zeta-pregnane-3,20-dione, 2 zeta,20 zeta-dihydroxy-4-pregnen-3-one, 2 alpha,3 alpha-dihydroxy-5 alpha- (and 5 beta)-pregnan-20-one, two isomers of pregnane-2,3,20-triol and 2 zeta,3 zeta,16 zeta-trihydroxy-5 zeta-pregnan-20-one.  相似文献   

19.
A total of 58 cultures, tentatively identified as species of the genus Cephalosporium, were screened in flask fermentations for their ability to effect conversions of progesterone (Delta(4)-pregnene-3,20-dione) and Reichstein's Substance S (Delta(4)-pregnene-17alpha,21-diol-3,20-dione). A large number of transformations were observed by means of a series of five paper chromatography systems rated for analysis of steroid compounds ranging in polarity from progesterone to polyhydroxylated steroids. Five different transformation products were selected for isolation and identification. For purposes of recovery, conversions were conducted under submerged conditions in either 4- or 200-liter fermentors in which the broth was agitated and aerated. The steroid substrate was dissolved in acetone and added aseptically to the growing culture in a final concentration of 0.025%. After the conversions were effected, the whole broth was extracted with chloroform, and the transformation products were recovered, either by direct crystallization from solvents or through the use of silica gel columns. It was determined that C. ciferrii 21C converted progesterone to Delta(4)-androstene-3,17-dione. Kendall's Compound F (Delta(4)-pregnene-11beta,17alpha,21-triol-3,20-dione) was converted to its 20beta-ol analogue by Geotrichum sp. 51C (during these studies, a number of cultures were taxonomically reclassified). Cephalosporium sp. 27C formed the Delta(1)-analogue of Reichstein's Substance S, and Cephalosporium sclerotigenum 31C and Verticillium aphidum both converted Substance S to the 6beta-hydroxy derivative. Paecilomyces persicinus 22C converted Substance S to a product believed to be a dihydroxylated derivative.  相似文献   

20.
The aim of this study was to determine the capacity of some progesterone derivatives, to inhibit the conversion of labeled androstenedione ([(3)H] 4-dione) to [(3)H]dihydrotestosterone ([(3)H]DHT) in prostate nuclear membrane fractions, where the 5α-reductase activity is present. The enzyme 5α-reductase catalyzes the 5α-reduction of 4-dione whereas the 17β-hydroxysteroid dehydrogenase catalyzes the transformation of 4-dione to testosterone or 5α-dione to dihydrotestosterone (DHT). Moreover, we also investigated the role of unlabeled 5α-dione in these pathways. In order to determine the inhibitory effect of different concentrations of the progesterone derivatives in the conversion of [(3)H] 4-dione to [(3)H]DHT, homogenates of human prostate were incubated with [(3)H] 4-dione, NADPH and increasing concentrations of non-labeled 5α-dione. The incubating mixture was extracted and purified using thin layer chromatography. The fraction of the chromatogram corresponding to the standard of DHT was separated and the radioactivity determined. The results showed that the presence of [(3)H] 4-dione plus unlabelled 5α-dione produced similar levels of DHT as compared to [(3)H] 4-dione. On the other hand, the results indicated that 17α-hydroxypregn-4-ene-3,20-dione 5 and 4-bromo-17α-hydroxypregn-4-ene-3,20-dione 7b, were the most potent steroids to inhibit the conversion of [(3)H] 4-dione to [(3)H]DHT, showing IC(50) values of 2 and 1.6?nM, respectively.  相似文献   

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