1-Amino-7-(2-carboxyphenylazo)-8-naphthol-3,6-disulfonic acid 2-[2-(8-Amino-1-hydroxy-3,6-disulfo-2-naphthalenyl)diazenyl]benzoic acid 8-Amino-1-hydroxy-2-(2′-carboxyphenylazo)naphthalene-3,6-disulfonic acid Benzoic acid, 2-[(8-amino-1-hydroxy-3,6-disulfo-2-naphthalenyl)azo]- Benzoic acid, 2-[2-(8-amino-1-hydroxy-3,6-disulfo-2-naphthalenyl)diazenyl]- Benzoic acid, o-(8-amino-1-hydroxy-3,6-disulfo-2-naphthylazo)-