4-chloro-3-[4-[(3-formylphenyl)azo]-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl]benzenesulphonic acid

4-Chloro-3-[[4-[(3-formylphenyl)azo]-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol]-1-yl]benzenesulfonic acid