马来酸酐 、
(4aS,4bR,8aS,9aR)-2,7-Diisopropenyl-4a,4b,6,8a,9,9a-hexahydro-3H-4,5-dioxa-fluorene 以
乙酸乙酯 为溶剂,
反应 21.0h,
以91%的产率得到(1R,2S,8S,12R,13S,14R,16S,17R,18S,22R)-6,24-dimethyl-3,10,20,27-tetraoxaheptacyclo[14.11.0.02,14.05,13.08,12.017,25.018,22]heptacosa-5,24-diene-9,11,19,21-tetrone