CAS 1020721-61-2 appears in our catalog under these names: 1-Methyl-1H-pyrazole-5-sulfonyl chloride, 95%, 1-Methyl-1H-pyrazole-5-sulfonyl chloride, 97% , 1-Methyl-1H-pyrazole-5-sulfonyl chloride, 98%, 1-Methyl-1H-pyrazole-5-sulfonyl chloride, 95.0%. Offered by: Combi-blocks, Thermo Scientific, Ambeed, BLDpharm, Fluorochem. Available pack sizes: 250mg, 1g, 5g, 10g, 100mg.