(R)-4-((3R,5S,7R,8R,9S,10S,12S,13R,14S,17R)-7,12-Bis-benzyloxymethoxy-3-hydroxy-10,13-dimethyl-hexadecahydro-cyclopenta[a]phenanthren-17-yl)-pentanoic acid 2,2,2-trichloro-ethyl ester 、
(R)-4-[(3R,5R,7R,8R,9S,10S,12S,13R,14S,17R)-7,12-Bis-benzyloxymethoxy-3-(tert-butyl-dimethyl-silanyloxy)-10,13-dimethyl-hexadecahydro-cyclopenta[a]phenanthren-17-yl]-pentanoic acid 在
4-二甲氨基吡啶 、
三乙胺 、
2,6-二氯苯甲酰氯 作用下,
以
二氯甲烷 为溶剂,
反应 1.5h,
以65%的产率得到7,12-bis[(benzyloxy)methoxy]-24-oxo-24-(2,2,2-trichloroethoxy)cholan-3-yl 7,12-bis[(benzyloxy)methoxy]-3-tert-butyldimethylsilyloxycholanoate