Naphthyridine studies. 15. 2-Styrylquinoline-3-carboxamides and their cyclization to 3-aryl-1-oxo-1,2,3,4-tetrahydrobenzo[b][1,6]naphthyridines

Condensation of 2-methylquinoline-3-carboxamides or the acid nitrile with benzaldehydes gave 2-styrylquinoline-3-carboxamides or the nitrile. It was shown that these compounds cyclize to the 2-substituted 3-aryl-1-oxo-1,2,3,4-tetrahydrobenzob]1,6]naphthyridines using pofyphosphoric acid or sulfuric acid.For Communication 14, see 1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 92–94, January, 1992.