Synthesis and Characterization of 6-Carbamoyl-1,2-dihydropurines

Abstract

The aromatic amines react readily with (Z)-N-(2-amino-1,2-dicyanovinyl)formimidate (4) to give the amidines (5a-b), which cyclize in the presence of DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) to give the corresponding 2-(5-Amino-1-phenyl-1H-imidazol-4-yl)-2-iminoacetonitrile (6a-b), which can be isolated. In the presence of aldehyde the formimidoylimidazole lead to novel 6-carbamoyl-1,2-dihydropurines (8a-b). All compounds have been fully characterized by spectroscopic data.