1,4,8,9-tetraazaspiro[5.5]undeca-2,7,10-triene-11-carboxylic acid, 2,3-dicyano-5-oxo- 2,3-dicyano-5-oxo-1,4,8,9-tetraazaspiro[5.5]undeca-2,7,10-triene-11-carboxylic acid InChI=1/C10H6N6O3/c11-1-6-7(2-12)16-10(9(19)15-6)4-14-13-3-5(10)8(17)18/h3-4,13,16H,(H,15,19)(H,17,18