A simple and efficient procedure has been described for the synthesis of 12-
methyl-7-phenylbenzo[h]naphtho[b][1,6]naphthyridin-8-ones 3a-g by the multicomponent reaction of 4-hydroxy-6-methylquinolin-2(1H)-one 1 with 1-naphthylamine 2
and a variety of aldehydes under microwave irradiation condition. The structures of the
newly synthesized compounds were confirmed by analytical and spectral (IR, NMR, and
Mass) data.