10H-Benzo(4,5)cyclohepta(1,2-b)thiophen-10-one, 4,9-dihydro-4-(1-methyl-4-piperidinylidene)-,(E)-2-butenedioate(1:1)
4-(1-Methyl-4-piperidylidene)-4H-benzo[4,5]cyclohepta[1,2-b] thiophen-10(9H)-one hydrogen fumarate