[(8S,9S,13S,14S)-17-[(3-bromopyridin-2-yl)methylidene]-13-methyl-7,8,9,11,12,14,15,16-octahydro-6H-cyclopenta[a]phenanthren-3-yl]oxy-tert-butyl-dimethylsilane 在
间氯过氧苯甲酸 作用下,
以43%的产率得到[(3'R,8R,9S,13S,14S,17R)-3'-(3-bromopyridin-2-yl)-13-methylspiro[7,8,9,11,12,14,15,16-octahydro-6H-cyclopenta[a]phenanthrene-17,2'-oxirane]-3-yl]oxy-tert-butyl-dimethylsilane