1H-Pyrazole-3-carboxylic acid, 4,5-dihydro-5-oxo-1-(4-sulfophenyl)-4-((4-sulfophenyl)azo)-, reaction products with guanidine hydrochloride N,N'-bis(mixed Ph, tolyl and xylyl) derivs. 71077-14-0 EINECS 275-170-4