1,5-Naphthalenedisulfonic acid, 3-((4,5-dihydro-3-methyl-5-oxo-1-(4-sulfophenyl)-1H-pyrazol-4-yl)azo)-, trisodium salt 62609-95-4 EINECS 263-637-5 Trisodium 3-((4,5-dihydro-3-methyl-5-oxo-1-(4-sulphonatophenyl)-1H-pyrazol-4-yl)azo)naphthalene-1,5-disulphonate