Synonyms: Ferrate(2-), (3-(4,5-dihydro-4-(2-(2-(hydroxy-kappaO)-5-nitrophenyl)diazenyl-kappaN1)-3-methyl-5-(oxo-kappaO)-1H-pyrazol-1-yl)benzenesulfonamidato(2-))(4-(4,5-dihydro-4-(2-(2-(hydroxy-kappaO)-5-nitrophenyl)diazenyl-kappaN1)-3-methyl-5-(oxo-kappaO)-1H-pyrazol-1-yl)benzenesulfonato(3-))-, sodium (1:2);Ferrate(2-), (3-(4,5-dihydro-4-((2-(hydroxy-kappaO)-5-nitrophenyl)azo-kappaN1)-3-methyl-5-(oxo-kappaO)-1H-pyrazol-1-yl)benzenesulfonamidato(2-))(4-(4,5-dihydro-4-((2-(hydroxy-kappaO)-5-nitrophenyl)azo-kappaN1)-3-methyl-5-(oxo-kappaO)-1H-pyrazol-1-yl)benzenesulfonato(3-))-, disodium;Ferrate(2-), (3-(4,5-dihydro-4-((2-hydroxy-5-nitrophenyl)azo)-3-methyl-5-oxo-1H-pyrazol-1-yl)benzenesulfonamidato(2-))(4-(4,5-dihydro-4-((2-hydroxy-5-nitrophenyl)azo)-3-methyl-5-oxo-1H-pyrazol-1-yl)benzenesulfonato(3-))-, disodium;iron(3+) sodium 4-{3-methyl-4-[(3-nitro-6-oxocyclohexa-2,4-dien-1-ylidene)diazanidyl]-5-oxopyrazol-2-id-1(5H)-yl}benzenesulfonate [(3-{[3-methyl-5-oxo-1-(4-sulfamoylphenyl)-1,5-dihydro-4H-pyrazol-4-ylidene]hydrazinylidene}-4-oxocyclohexa-1,5-dien-1-yl)imino]dioxidanide (1:2:1:1)