The synthesis of derivatives of 1,4,6-benzo[b]triazaphenothiazine, a novel aza-analog of phenothiazine, is described. The parent compound was obtained by base-catalysed condensation of 3-amino-2-mercaptopyridine with 2,3-dichloroquinoxaline in aqueous DMF. Several derivatives were also prepared by using the appropriately substituted aminomercaptopyridines and dichloro-quinoxalines. Nitration with mixed nitric and sulfuric acids gave the corresponding 13-nitro-1,4,6-benzo[b]triazaphenothiazine derivatives. The structures were elucidated by chemical evidence and by a study of their infrared, ultraviolet, pmr and mass spectra.
Journal of Heterocyclic Chemistry 01/1980; 17(1):149 – 153. DOI:10.1002/jhet.5570170130