2,7-Naphthalenedisulfonic acid, 4-amino-3-((2,5-dichlorophenyl)azo)-5-hydroxy-6-(1-naphthalenylazo)-, disodium salt 5850-34-0 Disodium 4-amino-3-((2,5-dichlorophenyl)azo)-5-hydroxy-6-(1-naphthylazo)naphthalene-2,7-disulphonate EINECS 227-448-1