4-溴苯甲酸 、
(2R)-2-[(3S,5S,6S,8S,10S,13S,14S,17S)-3,6-dihydroxy-10,13-dimethyl-2,3,4,5,6,7,8,12,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-17-yl]-2-hydroxy-6-methylheptan-3-one 在
4-二甲氨基吡啶 、
盐酸-N-乙基-Nˊ-(3-二甲氨基丙基)碳二亚胺 、
N,N-二异丙基乙胺 作用下,
以
二氯甲烷 为溶剂,
反应 2.0h,
以84%的产率得到(3S,5S,6S,8S,10S,13S,14S,17S)-17-((R)-2-hydroxy-6-methyl-3-oxoheptan-2-yl)-10,13-dimethyl-2,3,4,5,6,7,8,10,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthrene-3,6-diyl bis(4-bromobenzoate)