5-[(E,3R)-3-[(1R,3aS,4E,7aR)-4-[(2Z)-2-[(3S,4S,5R)-3,5-bis[[tert-butyl(dimethyl)silyl]oxy]-4-methyl-2-methylidenecyclohexylidene]ethylidene]-7a-methyl-2,3,3a,5,6,7-hexahydro-1H-inden-1-yl]but-1-enyl]-3-methylideneoxolan-2-one 在
lithium tetrafluoroborate 、
硫酸 作用下,
以
二氯甲烷 、
乙腈 为溶剂,
反应 3.0h,
生成 2(S)-methyl-20(R)-(2-(tetrahydro-3-vinylidene-2-furanon-5-yl)-1(E)-ethenyl)-9,10-secopregna-5(Z),7(E),10(19)-triene-1(S),3(R)-diol 、 2(S)-methyl-20(R)-(2-(tetrahydro-3-vinylidene-2-furanon-5-yl)-1(E)-ethenyl)-9,10-secopregna-5(Z),7(E),10(19)-triene-1(S),3(R)-diol