Synonyms: Cobaltate(2-), [4-[4,5-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-3-methyl-5-oxo-1H-pyrazol-1-yl]benzenesulfonamidato(2-)][3-[4,5-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-3-methyl-5-oxo-1H-pyrazol-1-yl]benzenesulfonato(3-)]-, sodium;Cobaltate(2-), 4-4,5-dihydro-4-(2-hydroxy-5-nitrophenyl)azo-3-methyl-5-oxo-1H-pyrazol-1-ylbenzenesulfonamidato(2-)3-4,5-dihydro-4-(2-hydroxy-5-nitrophenyl)azo-3-methyl-5-oxo-1H-pyrazol-1-ylbenzenesulfonato(3-)-, sodium