Methyl 3-aminothiophene-2-carboxylate (I) is acylated by 3-chlorobenzenesulfonyl chloride (II) to produce sulfonamide (III). After alkaline hydrolysis of the methyl ester group of (III), the resultant carboxylic acid (IV) is chlorinated by means of oxalyl chloride to furnish acid chloride (V). Finally, coupling of acid chloride (V) with 6-amino-2-methylbenzothiazole (VI) yields the title carboxamide.