27152-80-3 EINECS 248-267-4 Methanesulfonic acid, ((4-((4-nitrophenyl)azo)phenyl)amino)-, sodium salt Methanesulfonic acid, (p-((p-nitrophenyl)azo)anilino)-, monosodium salt Sodium (4-((4-nitrophenyl)azo)anilino)methanesulphonate