3,14,19-triacetylandrographolide 、
silver(I) acetate 在
碘 、
溶剂黄146 作用下,
反应 6.5h,
以72%的产率得到[(1S,4aS,5R,6R,8aS)-6-acetyloxy-5-(acetyloxymethyl)-1-[(2E)-2-[(4S)-4-acetyloxy-2-oxooxolan-3-ylidene]ethyl]-5,8a-dimethyl-1,4,4a,6,7,8-hexahydronaphthalen-2-yl]methyl acetate