United States Pharmacopeia (USP) Reference Standard Synonym(s): 3-[(Dimethylamino)methyl]-9-methyl-1,2,3,9-tetrahydro-4 H -carbazol-4-one hydrochloride; 3-[(Dimethylamino)methyl]-1,2,3,9-tetrahydro-9-methyl-4 H -carbazol-4-one Empirical Formula: C16H20N2O -+ HCl...