Nโฒ-[(4RS)-1-methylhexahydro-1H-azepin-4-yl]benzohydrazide hydrochloride (as per EP) ; N'-(1-methylazepan-4-yl)benzohydrazide hydrochloride,Nโฒ-[(4RS)-1-methylhexahydro-1H-azepin-4-yl]benzohydrazide hydrochloride (as per EP) ; N'-(1-methylazepan-4-yl)benzohydrazide hydrochloride,Azelastine Impurity