辛辣内酯A

Spiro[furo[2',3':5,6]cyclohepta[1,2-b]pyran-6(2H),6'(1'aH)-[5H]oxireno[4,5]cyclohepta[1,2-b]furan]-2,5'-dione,7-acetyl-2',3,3',3'a,3a,4,4a,6'a,7',7'a,8a,9,10,10a-tetradecahydro-8a-hydroxy-2',9-dimethyl-3-methylene-1'a-[(1E)-3-oxo-1-buten-1-yl]-,(1'aR,2'R,3'aS,3aR,4aR,6R,6'aR,7'aR,8aR,9S,10aR)-