96873-68-6 Pyridinium, 1,1'-(sulfonylbis(3,1-phenyleneimino(6-((3-((3-carboxy-4,5-dihydro-5-oxo-1-(4-sulfophenyl)-1H-pyrazol-4-yl)azo)-4-sulfophenyl)amino)-1,3,5-triazine-4,2-diyl)))bis(3-carboxy-, bis(inner salt), tetrasodium salt