3-乙酰氧基胆甾-5-烯-19-羟基-24-酮的制备与表征

Preparation and Structural Elucidation of 3β- acetoxy-19-hydroxy Cholest-5-en -24-one

通过3β-乙酰氧基-5-烯胆甾-24-酮(2)与N-溴代乙酰胺(NBA)反应得到3β-乙酰氧基-5α-溴-6β羟基胆甾-24-酮(3),(3)通过光环化反应后不经分离直接通过锌粉/乙酸水解得到52％产率的化合物3-乙酰氧基胆甾-5-烯-19羟基-24-酮(5)。缩短了合成天然多羟基甾醇24-亚甲基胆甾-5-烯-3β,7β,19-三醇(1)的时间并减少中间过程的物损耗,进一步提高了反应产率。

3β-acetoxy-19-hydroxy cholest-5-en-24-one (5) is an intermediate used for the synthesis of 24-methylenecholest-5-en-3β, 7β, 19-triol (1), a cytotoxic natural sterol from the marine organism. (5) was prepared in 52 % yield by the photocyclization and hydrolysis of 3β-acetoxy-5α-bromo-6βb-hydroxycholestane-24-one (3) which was obtained by the reaction of 3β-acetoxycholest-5-en-24-one (2) with N-bromoacetamide (NBA) .