2-Naphthalenesulfonic acid, 7-amino-4-hydroxy-3-((4-((4-sulfophenyl)azo)phenyl)azo)- 63147-42-2 7-Amino-4-hydroxy-3-((4-((4-sulphophenyl)azo)phenyl)azo)naphthalene-2-sulphonic acid EINECS 263-926-6