4-[(3-Chlorophenyl)Methyl]-2-(hexahydro-1-Methyl-1H-azepin-4-yl)-1(2H)-phthalazinone Azelastine Impuirty Azelastine Impuirty 4 HCl 1(2H)-Phthalazinone, 4-[(3-chlorophenyl)methyl]-2-(hexahydro-1-methyl-1H-azepin-4-yl)- 4-(3-chlorobenzyl)-2-(1-methylazepan-4-yl)phthalazin-1(2H)-one Azelastine Impurity 21 Azelastine 3-chloro isomer hydrochlorideQ: What is Azelastine 3-chloro isomer hydrochloride Q: What is the CAS Number of Azelastine 3-chloro isomer hydrochloride Azelastine 3-Chloro-Isomer