Synonyms: Sodium (4-hydroxy-3-((2-hydroxy-1-naphthyl)azo)benzenesulphonamidato(2-))(4-hydroxy-3-((5-hydroxynaphth(2,1-d)-1,3-oxathiol-4-yl)azo)benzenesulphonamide S,S-dioxidato(2-))cobaltate(1-);Cobaltate(1-), (4-hydroxy-3-((2-hydroxy-1-naphthalenyl)azo)benzenesulfonamidato(2-))(4-hydroxy-3-((5-hydroxynaphth(2,1-d)-1,3-oxathiol-4-yl)azo)benzenesulfonamide S,S-dioxidato(2-))-, sodium