A general method for the synthesis of benzimidazole-4-sulfonamides

A general method for the synthesis of benzimidazole-4-stilfonamides is described. This methodology employs commercially available benzothiadiazole-4-sulfonyl chloride as a benzimidazole equivalent. Reaction with a variety of amines followed by highly chemoselective reductive desulfurization gives intermediate 1,2-phenylenediamines, which may then react with aryl, heteroanyl, and alkyl aldehydes to provide substituted benzimidazole sulfonamides. (C) 2009 Elsevier Ltd. All rights reserved.