- First synthesis of a C-homosteroid from pregn-4-ene-3,11,20-trione
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(3α,5α)-3-Hydroxy-C-homopregnane-11,20-dione (3) was prepared in eleven steps from the commercially available pregn-4-ene-3,11,20-trione (4) via the 11-oxo-13-formyl-12,13-secopregnane intermediate 11 (Scheme 2). Subjection of this secopregnane to an intramolecular aldol condensation afforded the α,β-unsaturated key intermediate C-homopregn-12-en-11-one 12. Copyright
- Zhang, Zonglei,Wang, Lizhong,Bian, Xiaoqin,Sun, Qian,Xu, Hangxian,Wang, Cunde
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- NEUROACTIVE STEROIDS AND METHODS OF PREPARATION
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Disclosed are neuroactive steroid anaesthetic agents, methods for their preparation and compositions comprising the same. The invention provides scaled up and/or GMP methods for preparing neuroactive steroids, such as alfaxalone, alfadolone and alfadolone acetate.
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- Formation of 5α steroids by biotranformation involving the 5 α-reductase activity of Penicillium decumbens
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The biotransformation of a series of Δ4-3-ketosteroids by the Penicillium decumbens ATCC 10436 has been investigated. Conversion to the 5α-dihydrosteroid was observed substrates of the androsterone and pregne series: the reaction is tolerant of non-polar substituents (Cl and CH3) at C-4 of the substrate, but does not occur in the presence of a 4-hydroxyl group, or with additional unsaturation at the Δ1 or Δ6 positions. A-nor, B-nor, 3-deoxy-, and 3,5-cycloandrostanes are not reduced, but 6-methylenestestosterone is converted to a 6-methylene-5α-dihydro derivative. Several biotransformations are reported which involve oxidoreductase activity at C-3 and/or C-17, either concomitant or independent of Δ4 reduction: the substrate specificity of the oxidoreductase processes has been examined and defined by the use of 3α-hydroxy, 3β-hydroxy, 3-keto, 17β-keto substituted steroids. In this way, the existence in P. decumbens of 3β-hydroxy-3-keto and 17β-hydroxy-17-keto oxidoreductases has been demonstrated.
- Holland, Herbert L.,Dore, Sophia,Xu, Weili,Brown, Frances M.
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p. 642 - 647
(2007/10/02)
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