tetrasodium 2,2'-[(3,3'-dimethyl[1,1'-biphenyl]-4,4'-diyl)bis[imino[1-(1-hydroxyethylidene)-2-oxo-2,1-ethanediyl]azo]]bis[5-[[[(4-sulphonatophenyl)amino]carbonyl]amino]benzoate]

2,2'-[(3,3'-Dimethyl[1,1'-biphenyl]-4,4'-diyl)bis[imino[1-(1-hydroxyethylidene)-2-oxo-2,1-ethanediyl]azo]]bis[5-[[[[4-(sodiosulfo)phenyl]amino]carbonyl]amino]benzoic acid]disodium salt