Synthesis of 4-Amino-1H-pyrrolopyridine (1,7-Dideazaadenine) and 1H-Pyrrolopyridin-4-ol (1,7-Dideazahypoxanthine)

Article abstract of DOI:10.1021/jo01308a021

4-Amino-1H-pyrrolo<2,3-b>pyridine (1,7-dideazaadenine) (5) has been synthesized by the iron and acetic acid reduction of 4-nitro-1H-pyrrolo<2,3-b>pyridine 7-oxide (13), obtained by nitration of 1H-pyrrolo<2,3-b>pyridine-3-carboxamide 7-oxide (17).Other nitration reactions in the 1H-pyrrolo<2,3-b>pyridine 7-oxide series are disclosed.The preparation of 1H-pyrrolo<2,3-b>pyridin-4-ol (1,7-dideazahypoxanthine) (6) began with the hydrolysis of ethyl 1-benzyl-3-cyano-4-oxo-4,7-dihydro-1H-pyrrolo<2,3-b>pyridine-5-carboxylate (21) to the 3,5-dicarboxylic acid derivative of 1-benzyl-4-oxo-4,7-dihydro-1H-pyrrolo<2,3-b>pyridine (22).Decarboxylation of 22 with subsequent debenzylation formed 6.