Synthesis and Structure of 4-Indolyl-5-(thieno[3,2- b]pyrrol-6-yl)imidazoles.

A procedure was proposed for regioselective acylation of methyl 2-methyl-4 H-thieno[3,2- b]-pyrrole-5-carboxylate with 2-(3-indolyl)-2-oxoacetyl chloride. Reactions of the resulting methyl 6-[2-(3-indolyl)-1,2-dioxoethyl]-2-methyl-4 H-thieno[3,2- b]pyrrole-5-carboxylate with aromatic aldehydes and ammonium acetate in acetic acid afforded the corresponding methyl 6-[2-aryl-4-(3-indolyl)imidazol-5-yl]-2-methyl-4 H-thieno[3,2- b]pyrrole-5-carboxylates. The structure of methyl 6-[2-(4-chlorophenyl)-4-(3-indolyl)imidazol-5-yl]-2-methyl-4 H-thieno[3,2- b]pyrrole-5-carboxylate was studied by X-ray analysis. [ABSTRACT FROM AUTHOR]