74398-68-8 Benzenesulfonic acid, 2,5-bis((4-((3-methyl-5-oxo-1-(4-sulfophenyl)-4-pyrazolidinyl)azo)benzoyl)amino)-, trisodium salt Benzenesulfonic acid, 2,5-bis((4-((4,5-dihydro-3-methyl-5-oxo-1-(4-sulfophenyl)-1H-pyrazol-4-yl)azo)benzoyl)amino)-, trisodium salt