Development of methodologies for synthesis of 4-hydroxy-[1,5]naphthyridine-3-carbonitriles

4-Hydroxy-[1], [5] naphthyridine-3-carbonitrile derivatives were synthesized using two different eco-friendly methods, one of which is microwave assisted. Six derivatives were prepared using these methods and achieved good yields. 3-Aminopyridine and ester derivative are the starting materials required for the synthesis. In Method-A, microwave irradiation helps in achieving the reaction with a limited quantity of solvent and catalyst. Method-B is a conventional method wherein Dowtherm-A helps to attain high temperature required for the reaction. Both methods are found to be convenient, but the yield obtained through Method A (microwave assistance) is greater.