The molecule is an organosulfonate oxoanion resulting from the removal of a proton from both of the sulfo groups of 4-[(2,4-dimethylphenyl)diazenyl]-3-hydroxynaphthalene-2,7-disulfonic acid. It is a conjugate base of a 4-[(2,4-dimethylphenyl)diazenyl]-3-hydroxynaphthalene-2,7-disulfonic acid.
4-[(2,4-dimethylphenyl)diazenyl]-3-hydroxynaphthalene-2,7-disulfonate