分枝桿菌(Mycobacterium sp.M12)降解甾醇侧链的研究

分枝杆菌(Mycobacterium sp.M12)能将胆固醇,3β-乙酰氧基胆固醇,谷甾醇以及3β-乙酰氧基谷甾醇降解成△~3-雄甾烯-3,17-二酮(4AD)及少量的△~(1.4)-雄甾烯-3,17-二酮(ADD)。4AD的收率分别为69％,70％,26％,22％。对该菌株降解胆固醇侧链的最适条件进行了研究。     

β-谷甾醇侧链的降解:Δ~4-雄甾烯-3,17-二酮的生成

用牝牛分枝杆菌(Mycobacterium vaccae 209-20)切断β-谷甾醇(Ib)的侧链,获得△~4-雄甾烯-3,17-二酮(Ⅱ)和少量的△~(1.4)-雄甾烯-3,17-二酮(Ⅲ)。产物Ⅱ的收率为32％。     

5α-△~(9(11))-16β-甲基-3β,17α,21-三羟基-孕甾烯-3β,21-双醋酸酯-20酮和5α,17α-甲基-17β-羟基-雄甾-3酮的微生物转化

用诺卡氏菌与节杆菌混合菌种转化从蕃麻皂素制得的中间体5α-△~((?)(11))-16β-甲基-3β,17α,21三羟基孕甾烯-3β,21-双醋酸酯-20酮(Ⅰ)得50％的16β-甲基-△~(1,4,9(11))-孕甾三烯-20酮(Ⅱ)和少量的16β-甲基-9,11α环氧-△~1,4孕甾二烯-20酮(Ⅲ)。另外,又用同样的混合菌种转化从剑麻皂素制得的中间体5α,17α甲基-17β羟基-雄甾-3酮(Ⅳ)得50％17α甲基-17β羟基-△~(1,4)-雄甾二烯-3酮(Ⅴ)。如改变培养基则得3,17β-羟基-17α-甲基-9酮基-9,10开环-1,3,5(10)雄甾三烯化合物。     

睾丸酮对甲苯磺酸酯与醋酸钾在DMF中的反应机理

睾丸酮对甲苯磺酸酯(1b)在二甲基甲酰胺中与醋酸钾回流,可分离得到表睾丸酮(2a),表睾丸酮醋酸酯(2b),17-甲基-18-去甲基雄甾-4,13(17)-二烯-3-酮(3),雄甾-4,16-二烯-3-酮(4)和17-甲基-18-去甲基雄甾-4,13(14)-二烯-3-酮(5)。根据产物推测了此反应的机理。     

科研文摘

作者立体专一性地从雄甾-4-烯-3,17-二酮(Ⅰ)合成了17β-氰基-17α-羟基雄甾-4-烯-3-酮(Ⅱ)。Ⅰ与丙酮合氰化氢反应通常只得到17α-氰醇。如向Ⅰ的甲醇溶液加入过量的氰化钾,室温下滴入醋酸,则95％转化为Ⅱ。再经四步     

甲睾酮的合成

雄甾-4-烯-3,17-二酮经17-氰化、乙二醇保护3-酮基、去17-氰基和格氏反应等步骤得到激素类甾体药物甲睾酮,总收率77%,此路线未见文献报道.     

雄甾-4-烯-3,17-二酮Reformasky反应的试探

利用丰富的天然甾醇资源,经微生物切除17-位边链,能以较好的收率得到雄甾-4-烯-3,17-二酮(4-AD,1)或雄甾-1,4-二烯-3,17-二酮(ADD),因此应用这两个重要中间体合成各种甾体的化学工作受到普遍关注。以4-AD 或 ADD 为原料合成皮质激素的关键是研究一种有效的、适合于工业生产     

应用高速液相层析对甲雄烯诺龙同时进行鉴别、含量测定以及“其他甾体”的检查

鉴于甲雄甾烯诺龙[Methandrostenolone,去氢甲基睾丸素,即17β-羟基-17α甲基-甲基雄甾-1,4-二烯-3酮,(Ⅰ)]由化学或微生物合成过程中常含有与母体化合物相关的杂质[甲基睾丸素即17-β-羟基-17a-甲基雄甾一4一烯-3-酮,(Ⅱ);6d、17B-~-羟基17α-甲基雄甾-1,4-二烯-3-酮,(Ⅲ)和6β,17β-二羟基-17α-甲基雄甾-1,4-二烯-3酮,(Ⅳ)],致使现行的药典方法(英国药典及美国副药典所载多     

药品行政保护品种介绍:甾体药物(四)(续三)

依西美坦片剂 通用名:依西美坦(exemestane).商品名:Aromasin片剂,化学名:6-亚甲基雄甾-1,4-二烯-3,17-二酮.结构式见1.     

分枝桿菌(Mycobacterium sp.M12)降解甾醇侧链的研究

分枝杆菌(Mycobacterium sp.M12)能将胆固醇,3β-乙酰氧基胆固醇,谷甾醇以及3β-乙酰氧基谷甾醇降解成△³-雄甾烯-3,17-二酮(4AD)及少量的△^1.4-雄甾烯-3,17-二酮(ADD)。4AD的收率分别为69%,70%,26%,22%。对该菌株降解胆固醇侧链的最适条件进行了研究。     

Interactions of thiol-containing androgens with human placental aromatase

A series of thiol androgens were synthesized and investigated to characterize structural features important for the inhibition of aromatase. Analogues of androstenedione with thiol groups in either the 2 alpha-, 10 beta-, or 19-positions caused time-dependent inhibition of human placental aromatase. When their KI and kcat values were compared with those of 4-hydroxyandrost-4-ene-3,17-dione (4-OHa) and 10 beta-propargylestr-4-ene-3,17-dione (PED), the thiol androgen 10 beta-mercaptoestr-4-ene-3,17-dione (10 beta-SHnorA) proved to be the most potent suicide substrate. However, 19-mercaptoandrost-4-ene-3,17-dione (19-SHA) was the best all-around inhibitor. All compounds except 19-SHA exhibited normal type I P-450 difference spectra with partially purified/solubilized, human placental aromatase. The Ks values for the series of compounds compared qualitatively to the KI values determined from the time and concentration-dependent inhibition experiments. 19-SHA induced split Soret peaks at 380 and 474 nm, which suggested binding of the 19-thiolate directly to the ferric iron of aromatase. This binding could be displaced by aminoglutethimide but not by androstenedione. The inhibitory activity of 19-SHA may be explained by two independent mechanisms: (1) suicide inactivation of aromatase in the ferrous state; and (2) a direct "hyper-type II" binding to the remaining portion of the cytochrome in the ferric state. A free thiol group was necessary for the suicide inhibitory activity of 19-SHA; time-dependent inactivation of aromatase by 19-(acetylthio)androst-4-ene-3,17-dione (19-SAcA) and 19-xanthogenylandrost-4-ene-3,17-dione (19-XanA) could be prevented if the microsomes were preincubated with a carboxyesterase inhibitor. Aromatase previously inactivated by either thiol androgens,4-OHA, or PED could not be reactivated after incubation with the disulfide reducing agent dithiothreitol, which suggests that a disulfide bond may not be involved in aromatase inactivation by these inhibitors.     

Steroid 9alpha-hydroxylation during testosterone degradation by resting rhodococcus equi cells

The conversion pathway of testosterone to androst-4-ene-3,17-dione and 9alpha-hydroxy androstane metabolites, 9alpha-hydroxyandrost-4-ene-3,17-dione and 9alpha,17beta-dihydroxyandrost-4-en-3-one was proposed for the ring degradation in steroids by a minimal liquid medium (NMMP)-dispersed Rhodococcus equi ATCC 14887. The microorganism produced 9alpha-hydroxy androstane metabolites from testosterone at high conversion ratio without the addition of ring degradation inhibitory agents. Several NMMP-based media showed the similar effect on the microbial transformation, in which the respective molar yields of 9alpha-hydroxyandrost-4-ene-3,17-dione and 9alpha,17beta-dihydroxyandrost-4-en-3-one were approx. 3 to 47% and approx. 3 to 11%, respectively, whereas nutrient broth, a rich medium, basically showed no accumulation. On the basis of this evidence, magnesium sulfate and casamino acids among the components of NMMP were found to compromise the determinant for the production of the 9alpha-hydroxy androstane metabolites without appreciable decomposition of the steroid ring system.     

Altered regulation of cytochrome P-450 enzymes in choline-deficient cirrhotic male rat liver: impaired regulation and activity of the male-specific androst-4-ene-3,17-dione 16 alpha-hydroxylase, cytochrome P-450UT-A, in hepatic cirrhosis

Total microsomal cytochrome P-450 levels were decreased, to about 50% of control, in liver of male rats made cirrhotic by the prolonged intake of a choline-deficient diet. We have suggested previously that this decrease in cytochrome P-450 levels is not a generalized one, but is selective for certain forms of the enzyme. In the present study, levels of six cytochrome P-450 forms including the sex-specific cytochrome P-450 forms, P-450UT-A, P-450PCN-E, and P-450UT-l, were quantitated immunochemically in hepatic microsomes prepared from control and cirrhotic male rats and were related to changes in the regioselectivity of cytochrome P-450-mediated androst-4-ene-3,17-dione hydroxylation in these fractions. The principal finding of this study was that the male-specific androst-4-ene-3,17-dione 16 alpha-hydroxylase was decreased in cirrhotic microsomes to about 20% of control. The content of P-450UT-A decreased concurrently from about 0.40 to less than 0.01 nmol/mg of microsomal protein. Other pathways of androst-4-ene-3,17-dione hydroxylation were also affected, but to different extents than the 16 alpha-hydroxylase. 6 beta-Hydroxylation decreased in cirrhotic microsomes to about 45% of control, despite a marked decrease in P-450PCN-E from 0.27 to less than 0.002 nmol/mg of microsomal protein. The rate of androst-4-ene-3,17-dione 7 alpha-hydroxylation underwent a less pronounced reduction in cirrhosis to about two-thirds of control microsomal activity, and levels of the cytochrome P-450 associated with this activity, P-450UT-F, were decreased in proportion with the decrease in total microsomal cytochrome P-450. 16 beta-Hydroxylase activity was unaffected by the cirrhotogenic process. From spectral binding studies it was apparent that androst-4-ene-3,17-dione elicited a high affinity type I interaction in control microsomal fractions (Ks = 4.5 microM), whereas no interaction was apparent in cirrhotic liver microsomes. Levels of three other forms of cytochrome P-450--P-450PB-C (a constitutive form inducible by phenobarbital), P-450ISF-G (a major isosafrole-inducible form), and P-450UT-I (the major female sexually-differentiated isozyme)--were apparently unaltered in cirrhosis. These findings are consistent with the assertion that specific forms of cytochrome P-450 are subject to altered regulation in hepatic cirrhosis.     

脱氢诺龙醋酸酯的合成工艺研究

目的研究脱氢诺龙醋酸酯的合成工艺。方法以雌甾-4-烯-3,17-二酮为起始原料,经醋酸酐酯化、硼氢化钠还原、醋酸酐再酯化、N-溴代丁二酰亚胺(NBS)溴代、脱溴化氢5步反应合成脱氢诺龙醋酸酯。结果与结论目标化合物的结构经1H-NMR、IR谱等确证,总收率由文献报道的51%提高到68.1%。改进后的工艺路线反应条件温和、操作简便、收率高、成本低廉,有利于工业化生产。     

Photochemische Studien, 52. Mitt.: Untersuchungen zur Photostabilität von Testosteron und Methyltestosteron im kristallinen Zustand

Photochemical Studies LII: Investigation on the Photostability of Testosterone and Methyltestosterone in the Solid State Irradiation of testosterone in the solid state yields 4-androstene-3,17-dione and 5α-androstane-3,17-dione, while that of methyltestosterone leads to 17-methyl-13,17-seco-androst-4-ene-3,17-dione. For these light-induced transformations disproportionations are proposed as mechanism.     

Thiol-containing androgens as suicide substrates of aromatase

The thiol-containing androgens 17 beta-hydroxy-10 beta-mercaptoestr-4-en-3-one and 19-mercaptoandrost-4-ene-3,17-dione were synthesized and tested in human placental microsomes for their ability to suicide inhibit aromatase. Both compounds showed time-dependent, pseudo-first-order rates of inactivation of aromatase with Ki's of 106 and 34 nM and kcat's of 3.2 X 10(-3) and 1.2 X 10(-3) s-1 respectively for 1 and 2 at 30 degrees C. Diffusion dialysis failed to reactivate aromatase previously inactivated by either compound, and both compounds required that NADPH and O2 be present for the time-dependent inactivation of the enzyme. The presence of the substrate, androst-4-ene-3,17-dione (5.0 microM), protected the enzyme from inactivation while cysteine (1.0 mM) failed to protect aromatase from inactivation by either compound. The above evidence demonstrates that both compounds are potent suicide inhibitors of aromatase.     

唐古特山莨菪毛状根对去氢表雄酮的生物转化

目的通过生物转化对去氢表雄酮进行结构修饰，以期获得更有意义的转化产物。方法利用唐古特山莨菪毛状根液体悬浮培养体系对去氢表雄酮进行生物转化，通过柱色谱及制备薄层色谱进行分离纯化，利用核磁共振、ESI-MS等光谱鉴定结构。结果分离得到了5个转化产物，即：androst-4-ene-3,17-dione ( I)； 6α-hydroxyandrost-4-ene-3, 17-dione (II)；6α,17β-dihydroxyandrost-4-ene-3-one(III)； androst-4-ene-3,6,17-trione (IV)；17β-hydroxyandrost-4-ene-3-one (V)。结论所得到的5个化合物均为首次通过植物组织培养生物转化的方法从唐古特山莨菪毛状根液体培养体系中分离得到。     

Effect of 4-hydroxyandrost-4-ene-3,17-dione (formestane) on the bile secretion and metabolism of 4-(14)C-cholesterol to bile acids

4-Hydroxyandrost-4-ene-3,17-dione (formestane) is a selective aromatase inhibitor. It is indicated for postmenopausal patients with advanced breast cancer. The aim of the present study was to investigate the effect of 4-hydroxyandrost-4-ene-3,17-dione on the bile secretion and metabolism of 4-(14)C-cholesterol to bile acid. The experiments were carried out in the ovariectomized and sham-operated female Wistar rats. Formestane (20 mg/kg, i.m., daily) was administered to animals for 2 weeks. Twenty four hours after the last drug administration, rats were anesthetized with ethyl urethane. 4-(14)C-cholesterol (740 kBq/kg, s.a. 2.28 GBq/mmol) was infused for 1 min by catheter inserted into the jugular vein. Bile samples were assayed for total 14C radioactivity 14C-bile acids were determined in bile (after thin-layer chromatographic separation) by the use of isotopic technique with liquid scintillator. Previous studies showed that systemic adverse effects occurred in about 12% of patients following intramuscular drug administration. Many of them such as hot flushes, vaginal spotting and emotional lability were related to the mechanism of action of formestane i.e. estrogen suppression. Lethargy, rash, nausea, dizziness, indigestion, ataxia, cramps and facial swelling have also been reported. The results of the present study have shown that formestane administered to the female ovariectomized rats decreased the bile secretion and diminished conversion of 4-(14)C-cholesterol to trihydroxy bile acids. The decreased synthesis of trihydroxy bile acids and increased concentrations of cholesterol and litocholic acid in bile may be associated with increased risk of gallstone formation.     

Inhibition of rat liver microsomal cytochrome P-450 steroid hydroxylase reactions by imidazole antimycotic agents

The imidazole antimycotic agents ketoconazole, miconazole and clotrimazole were tested for their abilities to inhibit the reactions involved in the oxidative metabolism of androst-4-ene-3,17-dione by rat liver microsomal cytochromes P-450. All three compounds were found to function as potent inhibitors of steroid hydroxylase reactions, producing 50% inhibition of 6 beta-, 16 beta-, and 16 alpha-hydroxylase activities at concentrations between 10(-7) and 10(-5) M. The antimycotic agents, when added to liver microsomes, bound to cytochrome P-450 with high affinity to produce a "type II" spectral complex. These agents showed differential inhibition of the various steroid hydroxylases and were found not to affect the activities of the liver microsomal steroid 5 alpha-reductase or the androst-4-ene-3,17-dione 17-oxidoreductase. The results presented demonstrate an interaction of these imidazole antimycotic agents with the various cytochromes P-450 of liver microsomes, resulting in selective inhibition of monooxygenase activity.