(1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bS)-9-(4-(tert-butoxycarbonyl)phenyl)-5a,5b,8,8,11a-pentamethyl-1-(3-(methylamino)prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysene-3a-carboxylic acid 、
N,N-二异丙基乙胺 、
丁二酸单甲酯酰氯 在
4-二甲氨基吡啶 二氯甲烷 、
Sodium sulfate-III 、 expected product 作用下,
以
1,2-二氯乙烷 、
水 、
盐酸 为溶剂,
反应 3.0h,
以to give the expected product as a white solid (0.047 g, 0.062 mmol, 50% yield)的产率得到(1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bS)-9-(4-(tert-butoxycarbonyl)phenyl)-1-(3-(4-methoxy-N-methyl-4-oxobutanamido)prop-1-en-2-yl)-5a,5b,8,8,11a-pentamethyl-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysene-3a-carboxylic acid