CAS 5990-63-6 appears in our catalog under these names: rel-(2R,3S)-2,3-Dihydroxysuccinic acid hydrate/ 99.86% (existing batch purity), rel–(2R,3S)–2,3–Dihydroxysuccinic acid hydrate, meso-Tartaric acid monohydrate, Mesotartaric Acid Monohydrate, >90.0%(HPLC), MESO-TARTARIC ACID MONOHYDRATE, >=97%. Offered by: TargetMol, GLPBio, Biosynth, TCI, Sigma-Aldrich. Available pack sizes: 100mg, 200mg, 500mg, 1g, 25g, 5g, 250mg, 100 mg.