CAS 20583-31-7 appears in our catalog under these names: 3-(4-Nitrophenyl)pyrazole, 98%, 3-(4-Nitrophenyl)-2H-pyrazole, 98%, 3-(4-Nitrophenyl)-1H-pyrazole, 98%, 3-(4-Nitrophenyl)-1H-pyrazole, 97% , 3-(4-Nitrophenyl)-1H-pyrazole, 95%, 95%. Offered by: Combi-blocks, AmBeed, Thermo Scientific (Alfa Aesar), Chemat, Fluorochem. Available pack sizes: 1g, 10g, 5g, 250mg, 100mg, 2g.