2-Naphthalenesulfonic acid, 6-amino-4-hydroxy-5-((2-(phenoxysulfonyl)phenyl)azo)-, monosodium salt 70209-95-9 EINECS 274-392-9 Sodium 6-amino-4-hydroxy-5-((2-(phenoxysulphonyl)phenyl)azo)naphthalene-2-sulphonate