Acitazanolast can be obtained by two related procedures: 1) By condensation of 3-(1H-tetrazol-5-yl)aniline (I) with oxalyl chloride (II) in dimethoxyethane. 2) By condensation of the aniline (I) with ethyl oxalyl chloride (III) by means of triethylamine in DMF to the corresponding ethyl ester (IV), which is then hydrolyzed with base (KOH or NaOH) in ethanol.