- Hydroxyl groups at C-3 and at C-17 of the unnatural enantiomer, ent-androsta-5,9(11)-diene-3β,17β-diol are oxidised by cholesterol oxidase from Rhodococcus erythropolis
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The ent-androsta-4,9(11)-diene-3β,17β-diol 1b and ent-androsta-5,9(11)-diene-3β,17β-diol 2b prepared from chiral dione 3, were oxidised by cholesterol oxidase with kinetic parameters close to those of the natural steroids 1a and 2a. In the preparative oxi
- Kitamoto, Dai,Dieth, Serge,Burger, Alain,Tritsch, Denis,Biellmann, Jean-Fran?ois
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- Regio- and stereoselective reduction of 17-oxosteroids to 17β-hydroxysteroids by a yeast strain Zygowilliopsis sp. WY7905
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The reduction of 17-oxosteroids to 17β-hydroxysteroids is one of the important transformations for the preparation of many steroidal drugs and intermediates. The strain Zygowilliopsis sp. WY7905 was found to catalyze the reduction of C-17 carbonyl group of androst-4-ene-3,17-dione (AD) to give testosterone (TS) as the sole product by the constitutive 17β-hydroxysteroid dehydrogenase (17β-HSD). The optimal conditions for the reduction were pH 8.0 and 30 °C with supplementing 10 g/l glucose and 1% Tween 80 (w/v). Under the optimized transformation conditions, 0.75 g/l AD was reduced to a single product TS with >90% yield and >99% diastereomeric excess (de) within 24 h. This strain also reduced other 17-oxosteroids such as estrone, 3β-hydroxyandrost-5-en-17-one and norandrostenedione, to give the corresponding 17β-hydroxysteroids, while the C-3 and C-20 carbonyl groups were intact. The absence of by-products in this microbial 17β-reduction would facilitate the product purification. As such, the strain might serve as a useful biocatalyst for this important transformation.
- Liu, Yuanyuan,Wang, Yu,Chen, Xi,Wu, Qiaqing,Wang, Min,Zhu, Dunming,Ma, Yanhe
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- Synthesis of 11-substituted androstenediones and testosterones as human decidual cell growth inhibitors
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11α-Hydroxytestosterone (1a), 11β-hydroxytestosterone (1b), 11α- methoxytestosterone (1c), 11β-methoxytestosterone (1d), 11-ketotestosterone (1e), and Δ(9(11))-testosterone (1f) were synthesized from hydrocortisone (4b) or 11-epi-hydrocortisone (4a). The six target compounds, together with 11α-methoxyandrostenedione (2c), 11β-methoxyandrostenedione, (2d) and their lead compound, testosterone (1), were found to effectively inhibit the growth and differentiation of human decidual cells in culture. There is no observable binding of these compounds to estrogen receptor of rabbit uterus. The introduction of a polar group (e.g., hydroxyl and carbonyl) to C-11 of androstenes decreases both the relative binding affinities to progesterone receptor and the inhibitory effects on human decidual cell growth, while the methylation of 11-hydroxyl group minimizes these effects. The similar effects of a polar group at C-11 of testosterone (1) on the inhibitory effects on human decidual cell growth and the relative binding affinities to progesterone receptor of rabbit uterus may suggest that one of the mechanisms of human decidual cell growth inhibition by these compounds is the anti- progestational activity of these androgens.
- Zhao, Qinjian,Li, Zhensu
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p. 190 - 195
(2007/10/02)
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- Stereochimie - LXI - Steroides fluores - XII - Rearrangement spinal de l'hydroxy-17β epoxy-9,11α androstene-4 one-3
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Starting from Δ-9(11) dehydro testosterone 7a, it was possible to rearrange the corresponding 9-(11) α epoxide 11 to diketone 5, which incorporates a number of the structural features of euphol 3.By varying the experimental conditions, anhydrous HF treatment of epoxide 11 afforded the rearranged diketone 5, the addition compound, fluorohydrin 12, or the dehydration compound, diene 13 a.
- Audouin, Max,Levisalles, Jacques
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p. 1280 - 1284
(2007/10/02)
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