2-Naphthalenesulfonic acid, 4-hydroxy-3-((4-methoxy-2-sulfophenyl)azo)-7-(methylamino)- 4-Hydroxy-3-((4-methoxy-2-sulfophenyl)azo)-7-(methylamino)-2-naphthalenesulfonic acid 4-Hydroxy-3-((4-methoxy-2-sulphophenyl)azo)-7-(methylamino)naphthalene-2-sulphonic acid 51838-10-9 EINECS 257-464-4