Ondansetron Hydrochloride Dihydrate Standard

9-Methyl-3-((2-methyl-1H-imidazol-1-yl)methyl)-1,2,3,9-tetrahydro-4H-carbazol-4-one Hydrochloride Dihydrate; GR 38032F; 4H-Carbazol-4-one,1,2,3,9-tetrahydro-9-methyl-3-(2-methyl-1H-imidazol-1-yl)methyl-, Monohydrochloride,(±)-,Dihydrate; (±)-2,3-Dihydro-9-methyl-3-(2-methylimidazol-1-yl)methylcarbazol-4(1H)-one Monohydrochloride Dihydrate (USP);