bipinnatin B

2-[(1S,2S,4R,5R,10S,12R,14S,15S)-2,5-Bis(acetyloxy)-7,12-dimethyl-17-oxo-11,16,18,19-tetraoxapentacyclo[12.2.2.16,9.01,15.010,12]nonadeca-6,8-dien-4-yl]acrylaldehyde