乙酸酐 、
ixocarpalactone B 在
吡啶 作用下,
以9 mg的产率得到[(1S,2S,3'R,4S,4'R,6S,7S,8R,9R,10S,13S,14R,18S,19S,21R)-7,8-dihydroxy-3',4',8,10,14-pentamethyl-5',15-dioxospiro[5,20-dioxahexacyclo[11.9.0.02,10.04,9.014,19.019,21]docos-16-ene-6,2'-oxolane]-18-yl] acetate