Condensed isoquinolines 23. Reaction of <Emphasis Type="Italic">o</Emphasis>-bromomethylphenyl-acetonitrile with anthranilic acids: Synthesis of 6H, 12H,17H-dibenzo[3,4:6,7][1,8]-naphthyridino[1,8-<Emphasis Type="Italic">ab</Emphasis>]quinazoline-6,17-diones

The direction of the reaction of anthranilic acids with o-bromomethylphenylacetonitrile upon fusion depends on the temperature and nature of the substituent in the anthranilic acid. The reaction may lead to three types of products: Derivatives of 7,12-dihydro-5H-isoquino2,3-a]quinazolin-5-ones below 150°C and to 6,11-dihydro-13H-isoquino3,2-b]quinazolin-13-one or derivatives of 6H,12H,17H-dibenzo3,4:6,7]1,8]naphthyridino1,8-ab]quinazoline-6,17-diones above 150°C depending on the nature of the substituent in the anthranilic acid. A study was carried out on the mechanism for the formation of 6H,12H,17H-dibenzo3,4:6,7]1,8]naphthyridino1,8-ab]quinazoline-6,17-diones, which permitted the preparation of 6-(4-methylphenyl)-6,12-dihydro-5H-isoquino2,3-a]quinazolin-5-one. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1059–1067, July, 2007.