172701-51-8 1H-Pyrazole-3-carboxylic acid, 1-(3-chlorophenyl)-4-methoxy-5-((4-nitrophenyl)azo)-, ethyl ester Ethyl 1-(3-chlorophenyl)-4-methoxy-5-((4-nitrophenyl)azo)-1H-pyrazole-3-carboxylate