CAS 5963-77-9 appears in our catalog under these names: Pent–2–ynoic acid, 2-Pentynoic acid, 97% , 2-Pentynoic acid, 2-Pentynoic acid 95%, 2-PENTYNOIC ACID, 97%. Offered by: GLPBio, Thermo Scientific (Alfa Aesar), Biosynth, Ambeed, Sigma-Aldrich. Available pack sizes: 1g, 5g, 25g, 10g, 250mg, 100g.