4,5-Dihydro-4-[4-[2-(sulfooxy)ethylsulfonyl]phenylazo]-5-oxo-1-(4-sulfophenyl)-1H-pyrazole-3-carboxylic acid

4,5-dihydro-5-oxo-4-[[4-[[2-(sulphooxy)ethyl]sulphonyl]phenyl]azo]-1-(4-sulphophenyl)-1H-pyrazole-3-carboxylic acid