反应详情

0.9 g (3.75 mmol) of 2,3-diamino-5-ethylsulfanyl-benzoic acid ethyl ester was subjected to a similar cyclization condition as illustrated in intermediate A by using 1.2 g (11.3 mmol) of BrCN in methanol to produce 0.9 g (3.4 mmol, 90%) of 2-amino-6-ethylsulfanyl-1H-benzoimidazole-4-carboxylic acid ethyl ester. LCMS: 266 (M+1)+.