14507-49-4Relevant articles and documents
Preparation method of levonorgestrel intermediate ethyl lithium ammonia
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Paragraph 0028-0057, (2018/05/16)
The invention discloses a preparation method of levonorgestrel intermediate ethyl lithium ammonia. The preparation method includes the steps: (1) taking proton amine to react with alkali metal to prepare a reducing reagent; (2) taking organic solution of 18-methyl-3-methoxy-1, 3, 5 (10), 8-estratetraenol-17 beta-alcohol to react with the reducing reagent below 0 DEG C, and performing quenching, filtering, washing and draining to obtain a wet product; (3) adding the wet product into alcohol, performing refluxing, stirring, pulping and cooling, cooling the product at the temperature of -20 to 10DEG C for 4-24 hours, performing suction filtering, elution and draining, and drying the product at the temperature of 20-60 DEG C to reach constant weight to obtain the levonorgestrel intermediate ethyl lithium ammonia. The reducing reagent formed by proton amine is adopted to perform Birch reduction on 18-methyl-3-methoxy-1, 3, 5 (10), 8-estratetraenol-17 beta-alcohol, so that reaction temperature is increased, reaction difficulty is lowered, reaction yield and product purity are improved effectively, and environmental pollution caused in the reaction process is reduced.
SILICA GEL PROMOTED SELECTIVE HYDROLYSIS OF 3-METHOXY-2,5(10)-DIENE STEROIDS
Lui, Li-Gong,Zhang, Tong,Li, Zhen-Su
, p. 2999 - 3006 (2007/10/03)
Hydrolysis of 3-methoxy-2,5(10)-diene steroids (1a-c) via oxalic acid in the presence of silica gel was developed as a fast selective synthesis method toward corresponding 5(10)-en-3-ones (2a-c) in good yield (51-94percent).This also provided a new method for selective ketalisation of 17-keto over 3-keto (2c).
Total synthesis with a chirogenic opening move demonstrated on steroids with estrane or 18a-homoestrane skeleton
Quinkert,Del Grosso,Doring,Doring,Schenkel,Bauch,Dambacher,Bats,Zimmermann,Durner
, p. 1345 - 1391 (2007/10/02)
A concept of first choice for the synthesis of the title compounds had been proposed by Dane in the late 1930s. It was soon turned down, because the opening move - a chirogenic Diels-Alder reaction - did not work. With Lewis acids as mediators, however, a successful start has been achieved now. With Ti complexes of chelating ligands (Seebach's TADDOLs (= α,α,α',α'-tetraaryl-1,3-dioxolane-4,5-dimethanols)), enantioselective formation of the desired adducts does occur. Efficient total syntheses of 2 and 3a have been accomplished.
Direct Conversion of 13β-Alkylgonatetraenes into 13β-Alkylgon-4-en-3-ones
Bijoy, Panicker,Ramachandran, Uma,Rao, G. S. R. Subba
, p. 2331 - 2334 (2007/10/02)
Birch reduction of 8,9-didehydroestradiol-17β 3-methyl ether 1 or 9(11)-didehydroestradiol-17β 3 methyl ether 2 followed by acid hydrolysis results in a mixture of 19-nortestosterone 8 and 19-nor-9β,10α-testosterone 9 in varying amounts.However, reduction of their acetates with sodium or lithium, tert-butyl alcohol in liquid ammonia and in the presence of aniline affords exclusively 19-nortestosterone.Similarly, 18α-homo-19-nortestosterone 12 is prepared from the acetate of 18α-homoestradiol-17β 3 methyl ether, 10.
Synthesis of gon-4-enes
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, (2008/06/13)
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.
Synthesis of 13-alkyl-gon-4-ones
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, (2008/06/13)
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.
