2-Naphthalenesulfonic acid, 8-amino-5-(1-naphthalenylazo)-, monosodium salt 75627-23-5 8-Amino-5-(1-naphthalenylazo)-2-naphthalenesulfonic acid, sodium salt EINECS 278-277-4 Sodium 8-amino-5-(naphthylazo)naphthalene-2-sulphonate