4H,9H-Furo[2',3',4':4,5]naphtho[2,1-c]pyran-4,9-dione,1,2,3,3a,5a,6,6a,7,10b,10c-decahydro-7-methoxy-3a,10b-dimethyl-,(3aS,5aR,6aS,7S,10bS,10cR)- (9CI)