2-Amino-4-methylbenzothiazole → N-(4-methylbenzo[d]thiazol-2-yl)-1H-imidazole-1-carbothioamide

To 4-methylbenzo[d]thiazol-2-amine (1.1 g, 6.7 mmol) in acetonitrile (30 mL) was added 1,1′-thiocarbonyldiimidazole (1.552 g, 8.71 mmol). The reaction mixture was stirred at 50° C. for 18 hours. The reaction was cooled to room temperature and the precipitate was filtered and washed with acetonitrile (2×50 mL). The yellow powder was dried in a vacuum oven (50° C.) for 1 hour to yield N-(4-methylbenzo[d]thiazol-2-yl)-1H-imidazole-1-carbothioamide (900 mg, 3.28 mmol, 49% yield) and then used in the next step without any further purification or characterization.