Nitration of 3-substituted-4-hydroxy-2(1H)-quinolones 1 with nitric acid leads either to 3-nitro- 2 or 3-hydroxyquinolinediones 3, depending on the reaction conditions. 3-Substituted-3-hydroxyquinolinediones 3 are also obtained by oxidative hydroxylation with peracetic acid. Amination of 3-substituted-3-chloroquinolinediones 4 with ammonium hydroxide predominantly leads again to 3-substituted-3-hy
N-(α-Ketoacyl)anthranilicacids were prepared by oxidative ring opening of 3-hydroxyquinoline-2,4(1H,3H)-diones by using paraperiodic acid (H5IO6) or sodium periodate (NaIO4). The optimisation of the reaction conditions is described as well as the utilisation of N-(α-ketoacyl)anthranilicacids in the preparation of anthranilicacid hydrochlorides.