Abstract Some 3-substituted-5, 6-dihydro [1, 8] naphthyrido [3, 2-c][1, 8] naphthyridines (V) were obtained by the condensation of 7-substituted-2, 3-dihydro-1, 8-naphthyridin-4-(1H) ones (IV) with 2-aminonicotinaldehyde. All of the 5, 6-dihydro derivatives V were transformed into the fully aromatic compounds VI by refluxing with nitrobenzene.
[Laungani, Andy C.; Keller, Manfred; Slattery, John M.; Krossing, Ingo; Breit, Bernhard Chemistry - A European Journal, 2009 , vol. 15, # 40 p. 10405 - 10422]
