1-[2-Methyl-3-sulfo-5-(3,6-dichloro-4-pyridazinylcarbonylamino)phenyl]-4-(2-sulfophenylazo)-4,5-dihydro-5-oxo-1H-pyrazole-3-carboxylic acid

1-[5-[[(3,6-Dichloropyridazin-4-yl)carbonyl]amino]-2-methyl-3-sulfophenyl]-4,5-dihydro-5-oxo-4-[(2-sulfophenyl)azo]-1H-pyrazole-3-carboxylic acid

1-[5-[[(3,6-dichloropyridazin-4-yl)carbonyl]amino]-2-methyl-3-sulphophenyl]-4,5-dihydro-5-oxo-4-[(2-sulphophenyl)azo]-1H-pyrazole-3-carboxylic acid