Method for preparing ulipristal acetate and key intermediate thereof
申请人:Utopharm(Shanghai) Co., Ltd
公开号:US20140296510A1
公开(公告)日:2014-10-02
A method as well as new intermediates for preparing Ulipristal acetate (a compound I) and a method for preparing the new intermediates are provided. The intermediate in a constitutional formula IV is conductive to reacting with methyl lithium or methyl Grignard reagent, a protective group is easy to be removed after a reaction, side reactions are few, a mid-term treatment is simple, the reagents used are cheap, costs are low and a yield is high, if a compound in a constitutional formula V is obtained by the reaction of a compound in a constitutional formula III and the intermediate in the constitutional formula IV, the yield of a two-step reaction is 75%, a purity is above 98%.
wherein R is defined in the specification.