7H,9H-9a,6a-Propenofuro[3′,4′:5,6]naphth[2,1-c]oxireno[d]pyran-3,6,14(1H,3aH)-trione,1-(3-furanyl)-4b,5,9b,10,11,11a-hexahydro-5-hydroxy-4b,7,7,11a-tetramethyl-,(1S,3aS,4aR,4bS,5S,6aR,9aS,9bR,11aS)- (