Pyrolysis of appropriate derivatives of 8-nitropyridotetrazole brought about the formation of 5- methyl-, 5-carboxy-and 5-carbomethoxy-2, 3-~-dinitrosopyridine. Hydroxylamine in diethylamine or in triethanolamine reduced+ o-dinitrosobenzene to a dioxime (presumably amphi) of o-benzquinone. Similar treatment of 5-methyl-2, 3-(~-dinitrosopyridine brought about reduction together with amination. The product appeared to be a dioxime of 3-aza-4 ...