劳森试剂 、 3β,28-diacetoxylup-20(29)-en-30-al 以
甲苯 为溶剂,
反应 4.0h,
以40%的产率得到[(1R,3aS,5aR,5bR,7aR,9S,11aR,11bR,13aR,13bS)-9-acetyloxy-1-[(2R)-2-(4-methoxyphenyl)-2-sulfanylidene-4H-1,3,2lambda5-oxathiaphosphinin-5-yl]-5a,5b,8,8,11a-pentamethyl-1,2,3,4,5,6,7,7a,9,10,11,11b,12,13,13a,13b-hexadecahydrocyclopenta[a]chrysen-3a-yl]methyl acetate