1-(3,4-Diethoxybenzylidene)-6,7-diethoxy-1,2,3,4-tetrahydroisoquinoline 1-Benzyl-3',4',6,7-tetraethoxy-1,2,3,4-tetrahydroisoquinoline 14009-24-6 985-12-6 DROTAVERINE HYDROCHLORIDE Drotaverin Drotaverina [INN-Spanish] Drotaverine [INN] Drotaverinum [INN-Latin]