1,2,3,4-Tetrahydro-6,7-dimethoxyisoquinoline hydrochloride 1745-07-9 2328-12-3 6,7-Dimethoxy-1,2,3,4-tetrahydroisoquinoline hydrochloride Heliamine hydrochloride ISOQUINOLINE, 1,2,3,4-TETRAHYDRO-6,7-DIMETHOXY-, HYDROCHLORIDE Isoquinoline, 6,7-dimethoxy-1,2,3,4-tetrahydro-, hydrochloride NSC 18443