Colorimetric determination of some hydrazone derivatives

ABSTRACT

A simple and rapid colorimetric method was described for the determination of isocarboxazid, iproniazid phosphate and phenylhydrazine hydrochloride. The method depended on the use of 2-iodoxybenzoic acid, as an oxidant in 50% w/v orthophosphoric acid to oxidize chlorpromazine HCl to chlorpromazine free radical, which absorbs at 530 mm. This red free radical was rapidly and quantitatively reduced by the investigated compounds to the colorless chlorpromazine. The decrease in absorbance was found to be directly proportional to the quantity of each compound studied, and this forms the basis for the quantitative estimation of micro-quantities of the investigated compounds