Synonyms: disodium 4-[(2,4-diaminophenyl)azo]-4'-[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo][1,1'-biphenyl]-2,2'-disulphonate;4-[(2,4-Diaminophenyl)azo]-4'-[[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol)-4-yl]azo]-1,1'-biphenyl-2,2'-disulfonic acid disodium salt;Disodium 4-((2,4-diaminophenyl)azo)-4'-((4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo)(1,1'-biphenyl)-2,2'-disulphonate;Einecs 282-348-5