CAS 137-44-0 appears in our catalog under these names: 1H–Pyrazol–5(4H)–one, 5-Pyrazolone, >98.0%(GC), 1H-Pyrazol-5(4H)-one 95%, 1H-Pyrazol-5(4H)-one, 97%, 97%, 1H-Pyrazol-5(4H)-one, 97%. Offered by: GLPBio, TCI, Ambeed, Chemat, Fluorochem. Available pack sizes: 1g, 25g, 5g, 200mg, 250mg, 10g, 100g.