2-{[9-(1-methoxycarbonyl-ethylaminooxalyloxy)-8-(1-methoxycarbonyl-ethylcarbamoyl)-5a,5b,8,11a-tetramethyl-1-(4-methyl-2-oxo-[1,3]dioxolan-4-yl)-eicosahydro-cyclopenta[a]chrysene-3a-carbonyl]-amino}-propionic acid methyl ester 在
氢氧化钾 作用下,
以
甲醇 为溶剂,
以86%的产率得到(S)-2-{[(1R,3aS,5aR,5bR,7aR,8S,9R,11aR,11bR,13aR,13bS)-8-((S)-1-Carboxy-ethylcarbamoyl)-1-(1,2-dihydroxy-1-methyl-ethyl)-9-hydroxy-5a,5b,8,11a-tetramethyl-icosahydro-cyclopenta[a]chrysene-3a-carbonyl]-amino}-propionic acid