(R)-4-[(3S,5R,7R,8R,9S,10S,12S,13R,14S,17R)-7,12-Dihydroxy-3-(5-hydroxy-pentyloxy)-10,13-dimethyl-hexadecahydro-cyclopenta[a]phenanthren-17-yl]-pentanoic acid 在
高氯酸 吡啶 、
sodium hydroxide 、
氯化亚砜 作用下,
以
甲苯 为溶剂,
生成
(R)-4-[(3S,5R,7R,8R,9S,10S,12S,13R,14S,17R)-7,12-Dihydroxy-3-(5-hydroxy-pentyloxy)-10,13-dimethyl-hexadecahydro-cyclopenta[a]phenanthren-17-yl]-pentanoic acid tert-butyl ester