(1S,5R,6R)-3-(3-hydroxy-3-methylbut-1-enyl)-5-triethylsilanyloxy-7-oxabicyclo[4.1.0]hept-3-enone 生成 (1S,2S,3R,4R,6S,10S,13R,14S,16R,17R,18S)-13-hydroxy-18-[(E)-3-hydroxy-3-methylbut-1-enyl]-11,11-dimethyl-3,17-bis(triethylsilyloxy)-5,12,15-trioxahexacyclo[8.7.1.02,8.04,6.013,18.014,16]octadec-8-en-7-one