(-)-Isomethadone hydrochloride 3-Hexanone, 6-(dimethylamino)-4,4-diphenyl-5-methyl-, hydrochloride, (S)- 3-Hexanone, 6-(dimethylamino)-5-methyl-4,4-diphenyl-, hydrochloride, (-)- 6-(Dimethylamino)-4,4-diphenyl-5-methyl-3-hexanone hydrochloride (S)- 7487-81-2 Isomethadone l-form hydrochloride Levoisomethadone hydrochloride NIH 2961 l-Isomethadone hydrochloride