1-Naphthalenesulfonic acid, 2-((1-(2-chloro-5-sulfophenyl)-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-4-yl)azo)-, disodium salt 6359-95-1 Disodium 2-((1-(2-chloro-5-sulphonatophenyl)-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-4-yl)azo)naphthalene-1-sulphonate EINECS 228-815-9