- Preparation method of levonorgestrel
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The invention discloses a preparation method of levonorgestrel, and belongs to the technical field of medicine preparation and processing. According to the method, 18-methylestra-2,5(10)-diene-3-methoxy-17-ketone is used as an initial raw material, and the levonorgestrel disclosed by the invention is prepared by virtue of two steps of ethynylation and hydrolysis. According to the preparation method of the levonorgestrel, the defects of a traditional process are overcome and reaction conditions are mild; the method is high in overall conversion rate, easy and convenient to operate, suitable forindustrial production and wide in market prospect.
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Paragraph 0025-0026; 0028-0029; 0031-0032
(2020/09/20)
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- PROCESS FOR PREPARATION OF LEVONORGESTREL
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The present invention provides an improved process for preparation of levonorgestrel (3) which comprises of hydrolysis of 13β-ethyl-3-methoxy-17α-ethynyl-gona-2,5(10)-dien-17β-ol (2) with an acid in aprotic solvent. The present invention also provides a novel process for purification of crude levonorgestrel (3) by recrystallization from N,N-dimethyl formamide-water; methanol-water mixture.
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Paragraph 0047
(2014/01/07)
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- AN IMPROVED PROCESS FOR PREPARATION OF LEVONORGESTREL
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The present invention provides an improved process for preparation of levonorgestrel (3) which comprises of hydrolysis of 13 β-ethyl-3-methoxy-17α-ethynyl-gona-2,5(10)-dien-17β- o1 (2) with an acid in aprotic solvent. The present invention also provides a novel process for purification of crude levonorgestrel (3) by recrystallization from N,N-dimethyl formamide- water; methanol-water mixture.
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Page/Page column 9
(2012/09/10)
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- Synthesis of gon-4-enes
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1. A therapeutic composition having progestational activity comprising as active ingredient a 17-aliphatic carboxylic acid ester of 17α-ethynyl-18-methyl-19-nortestosterone and a pharmaceutical carrier for said compound.
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- Synthesis of 13-alkyl-gon-4-ones
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The preparation of 13-methylgon-4-enes and novel 13-polycarbonalkylgon-4-enes by a new total synthesis is described. 13-Alkylgon-4-enes having progestational, anabolic and androgenic activities are prepared by forming a tetracylic gonane structure unsaturated in the 1,3,5(10),9(11) and 14-positions, selectively reducing in the B- and C-rings, and converting the aromatic A-ring compounds so-produced to gon-4-enes by Birch reduction and hydrolysis.
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