(1R,8S,9S)-3,4,8-trihydroxy-11,11-dimethyl-5-propan-2-yl-16-oxatetracyclo[7.5.2.01,10.02,7]hexadeca-2,4,6-trien-15-one 、
重氮甲烷 生成 (1R,9R,10S)-3,4-dimethoxy-12,12-dimethyl-5-propan-2-ylspiro[17-oxatetracyclo[8.5.2.01,11.02,7]heptadeca-2,4,6-triene-9,2'-oxirane]-16-one