2,7-Naphthalenedisulfonic acid, 5-((4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo)-4-hydroxy-3-((2-hydroxy-3-nitro-5-sulfophenyl)azo)-, trisodium salt 72152-58-0 EINECS 276-411-6 Trisodium 5-((4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo)-4-hydroxy-3-((2-hydroxy-3-nitro-5-sulphonatophenyl)azo)naphthalene-2,7-disulphonate