Synonyms: Cobaltate(1-),[2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)][1-[(2-hydroxy-4-nitrophenyl)azo]-2-naphthalenolato(2-)]-,hydrogen; Cobaltate(1-), [2,4-dihydro-4-[[2-(hydroxy-kO)-5-nitrophenyl]azo-kN1]-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)-kO3][1-[[2-(hydroxy-kO)-4-nitrophenyl]azo-kN1]-2-naphthalenolato(2-)-kO]-, hydrogen (9CI);2-Naphthalenol, 1-[(2-hydroxy-4-nitrophenyl)azo]-, cobalt complex; 3H-Pyrazol-3-one,2,4-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-5-methyl-2-phenyl-, cobalt complex