CAS 16504-56-6 appears in our catalog under these names: (R)–3–Amino–4–hydroxybutanoic acid, L-beta-Homoserine, H-β-HoSer-OH 98%, (R)-3-Amino-4-hydroxybutanoic acid, 97%, 97%, (R)-3-Amino-4-hydroxybutanoic acid, 97.0%. Offered by: GLPBio, Biosynth, Ambeed, Chemat, MedChemExpress. Available pack sizes: 1g, 5g, 250mg, 100mg, 1 g, 250 mg, 100 mg.