5-chloro-3-[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo]-2-hydroxybenzenesulphonic acid

5-Chloro-3-[[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol)-4-yl]azo]-2-hydroxybenzenesulfonic acid