ethyl (-)-(E)-4-{(3aS,4S,7R,7aS)-7-hydroxy-7-[(4R,5S,E)-4-methyl-5-(triethylsilyloxy)hex-2-enyl]tetrahydro-3aH-spiro[[1,3]dioxolo[4,5-c]pyran-2,1'-cyclohexan]-4-yl}-3-methylbut-2-enoate 在
dowex 作用下,
以
甲醇 为溶剂,
反应 120.0h,
以80%的产率得到ethyl (+)-(E)-3-methyl-4-[(2S,3R,4S,5R)-3,4,5-trihydroxy-5-((4R,5S,E)-5-hydroxy-4-methylhex-2enyl)tetrahydro-2H-pyran-2-yl]but-2-enoate