Abstract The imidazo [1, 2-a] pyridine system was investigated as a synthon for the building of very attractive fused triazines, a planar, angular tri-heterocycle with potential biological activity. Thus ethyl 3-nitroimidazo [1, 2-a] pyridine-2-carboxylate was treated with ammonia or with an excess of primary amines to generate the corresponding substituted nitro carboxamidoimidazopyridines. The nitro substituent in the latter products, was reduced to ...