Preparation
2,4-Diaminobenzenesulfonic acid?and?2,4,6-Trichloro-1,3,5-triazine?condensation, its product (2 Moore) diazo, and?5-Oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid?(2 Moore) coupling, and 5-Oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid (2 moles) of the coupling and then with 1,2-Bis(4-amino-2-sulfophenyl)ethene? condensation.
