反应详情

4.0 g (17.9 mmol) of 2,3-diamino-5-ethoxy-benzoic acid ethyl ester was subjected to a similar cyclization condition as illustrated in intermediate A by using 5.7 g (53.7 mmol) of BrCN in methanol to produce 2-amino-6-ethoxy-1H-benzoimidazole-4-carboxylic acid ethyl ester. LCMS: 250 (M+1)+.