{"Abbreviation":["Thr"],"Absorption, Distribution and Excretion":"Although the free amino acids dissolved in the body fluids are only a very small proportion of the body's total mass of amino acids, they are very important for the nutritional and metabolic control of the body's proteins. ... Although the plasma compartment is most easily sampled, the concentration of most amino acids is higher in tissue intracellular pools. Typically, large neutral amino acids, such as leucine and phenylalanine, are essentially in equilibrium with the plasma. Others, notably glutamine, glutamic acid, and glycine, are 10- to 50-fold more concentrated in the intracellular pool. Dietary variations or pathological conditions can result in substantial changes in the concentrations of the individual free amino acids in both the plasma and tissue pools. /Amino acids/","Aliases":["72-19-5","2-amino-3-hydroxybutanoic acid","Threonin","2-amino-3-hydroxybutyric acid","Treonina","2-Amino-3-hydroxybutyric acid","Threoninum","thr","(2S)-threonine","α-Amino-β-hydroxybutyric acid","Fema no. 4710","NSC-16589","NSC-46701","2ZD004190S","Dtxcid0026412","Chebi:16857","(R-(R*,S*))-2-Amino-3-hydroxybutanoic acid","[R-(R*,S*)]-2-Amino-3-hydroxybutanoic acid","l threonine","Threonine High","Threonine 7425","Threonine High 7426","Chebi:26986","200-774-1","2-azaniumyl-3-hydroxybutanoate","H-Thr-OH","Threonine, L-","thre","Mfcd00064270","2-Amino-3-hydroxybutanoic acid, (R-(R*,S*))-","Butanoic acid, 2-amino-3-hydroxy-, (R-(R*,S*))-","6028-28-0","H-DL-Thr-OH","NSC46701","rel-2-Amino-3-hydroxybutanoic acid","M02962","Threonine #","Cas-72-19-5","(R-(R*,S*))-2-Amino-3-hydroxybutanoate","[R-(R*,S*)]-2-Amino-3-hydroxybutanoate","(U-14C)Threonine","Einecs 200-774-1","NSC 16589","NSC 46701","Threonine CRS","HSDB 7797","NSC-206292","Ncgc00164520-01","Ncgc00164520-02","H-Thr","Thr-OH","Threonine, labeled with carbon-14, L-","2-Amino-3-hydroxybutyrate","bmse000049","bmse000810","bmse000859","2-Amino-3-hydroxybutanoate","Schembl1480","Threonine non-animal source","CCRIS 8603","Chembl291747","GTPL4785","orb1304729","orb3025613","orb3029197","orb3140665","Schembl6517407","Schembl28344457","HY-N0658R","MSK1417","α-Amino-β-hydroxybutyrate","Pharmakon1600-01301008","HY-N0658","Einecs 201-300-6","Tox21_112154","AC7878","EBC-26050","NSC760118","s4951","Akos006240505","Akos015840277","Tox21_112154_1","CCG-214540","CS-W020046","DB00156","FT03495","NSC 206292","NSC-760118","T2O2777","7013-32-3","AC-11296","AS-12789","Threonine, BioXtra, \u003e=99.5%","Threonine, p.a., 99.0-101.0%","2-amino-3-hydroxy-butanoic acid","AI3-18477","DB-029984","rel-2-Amino-3-hydroxybutanoicacid","[R-(R*,S*)]-2-amino-3-hydroxy-Butanoate","NS00001961","NS00078877","En300-54609","Threonine, reagent grade, \u003e=98%","C00188","D00041","G76695","Sbi-0633502.0002","T13656","[R-(R*,S*)]-2-amino-3-hydroxy-Butanoic acid","Threonine(Discontinued,SeeCPTD788402)","Q186521","3Dd2e9ad-db9a-460e-8a6b-c01b0f67ac4e","Brd-k75508643-001-02-6","Lysine hydrochloride impurity c","48: PN: WO2004076659 FIGURE: 7 claimed sequence","F8881-8883","Threonine, certified reference material, TraceCERT(R)","Z813019058","Threonine, European Pharmacopoeia (EP) Reference Standard","Threonine, United States Pharmacopeia (USP) Reference Standard","Threonine, Pharmaceutical Secondary Standard; Certified Reference Material","Threonine, from non-animal source, meets EP, JP, USP testing specifications, suitable for cell culture, 99.0-101.0%"],"CAS":"80-68-2","Chemical Classes":"Biological Agents -\u003e Amino Acids and Derivatives","ChemicalClasses":["amino acid"],"Chirality":"achiral","ChiralityAminoAcid":true,"Color/Form":"Colorless crystals","DTXSID":"2046412","Decomposition":"When heated to decomposition it emits toxic fumes of /nitric oxide/.","Drug Indication":"L-Threonine makes up collagen, elastin, and enamel protein. It aids proper fat metabolism in the liver, helps the digestive and intestinal tracts function more smoothly, and assists in metabolism and assimilation.","Drug Warnings":"... In this placebo-controlled crossover study, the effect of supplemental oral threonine (THR) on the plasma amino acid concentrations of 12 patients with hyperphenylalaninemia was investigated. Before starting the first treatment period of this cross-over study, the patients were randomly assigned to one of two groups supplemented either with approximately 50 mg THR/kg per day or with a similar amount of maltodextrin as placebo. After a feeding period of 8 weeks and a wash-out period of 8 weeks, the supplements were crossed over and the study continued for an additional 8 weeks. Blood was obtained at the start and the end of each supplementation period.  Dietary THR supplementation of approximately 50 mg/kg per day resulted in a significant decrease of plasma phenylalanine (PHE) levels ( P = 0.0234). There was a close positive correlation between plasma and urinary PHE concentrations ( P \u003c 0.001) indicating that the lower plasma PHE levels in the THR supplemented patients were not caused by higher urinary excretion of PHE. CONCLUSIONS: The data of the present study show that oral THR supplementation has a clear plasma-PHE-reducing effect but they do not allow any conclusion about the mechanisms responsible for the observed effect. Although it seems attractive on the basis of the present data to use THR supplementation in patients with hyperphenylalaninemia, the mechanism of the observed effect should be clarified before introduction of such a treatment in these patients.","Druglikeness":{"Lipinski":{"Passes":true,"Violations":0}},"Erowid Experience Reports":[],"Esters":[],"European Community (EC) Number":"200-774-1","Formating":[],"HMDB ID":"HMDB0000167","HeavyAtomCount":8,"IUPACName":"(2S,3R)-2-amino-3-hydroxybutanoic acid","InChI":"InChI=1S/C4H9NO3/c1-2(6)3(5)4(7)8/h2-3,6H,5H2,1H3,(H,7,8)/t2-,3+/m1/s1","InChIKey":"AYFVYJQAPQTCCC-GBXIJSLDSA-N","Interactions":"A methionine-threonine-supplemented low (8.5%) casein diet (8.5CMT) reduced symptoms such as proteinuria in nephritic rats without severe protein malnutrition. ... This study ...  examined whether or not L-arginine supplementation to 8.5CMT would exacerbate proteinuria and other symptoms in nephritic rats. Male Wistar rats with glomerulonephritis induced by a single intravenous injection of nephrotoxic serum were fed either a 20% casein diet (control), 8.5% casein diet, 8.5CMT, or L-arginine-supplemented 8.5CMT (8.5CMTA) for 16 days. The 8.5CMTA, as compared with the 8.5CMT, aggravated proteinuria and glomerulonephritis. Administration of L-N(G)-nitroarginine methyl ester, an inhibitor of nitric oxide synthase, to 8.5CMTA-fed nephritic rats by drinking water for 14 days canceled the adverse effect of L-arginine on proteinuria and histopathological damage in glomeruli. These results suggest that the supplementation of L-arginine makes exacerbation via nitric oxide production in glomerulonephritis.","MeSH Headers":[{"Id":"M0021415","Link":"https://id.nlm.nih.gov/mesh/M0021415.html","Name":"Threonine","Ref":194},{"Id":"DescTree","Link":"https://www.nlm.nih.gov/mesh/meshhome.html","Name":"MeSH Tree","Ref":196},{"Id":"PubMed from MeSH","Link":"https://www.nlm.nih.gov/mesh/meshhome.html","Name":null,"Ref":223}],"Mechanism of Action":"L-Threonine is a precursor to the amino acids glycine and serine. It acts as a lipotropic in controlling fat build-up in the liver. May help combat mental illness and may be very useful in indigestion and intestinal malfunctions. Also, threonine prevents excessive liver fat. Nutrients are more readily absorbed when threonine is present.","Melting Point":"256 °C","Metabolism/Metabolites":"Hepatic","MolecularFormula":"C\u003csub\u003e4\u003c/sub\u003eH\u003csub\u003e9\u003c/sub\u003eNO\u003csub\u003e3\u003c/sub\u003e","MolecularWeight":"119.12 g/mol","Non-Human Toxicity Values":"LD50 rat ip 3098 mg/kg","Opticalactivity":"( + / - )","Passes":true,"Pharmacodynamics":"L-Threonine is an essential amino acid that helps to maintain the proper protein balance in the body. It is important for the formation of collagen, elastin, and tooth enamel, and aids liver and lipotropic function when combined with aspartic acid and methionine.","Physical Description":"Solid; [Merck Index]","PubChemId":6288,"PubChemTitle":"L-Threonine","Records":{"UNII":{"Impurities":[]}},"RefChem":"9314","RefCount":3,"RefCur":"","References":[{"Name":"Wikipedia","Urls":[{"Link":"https://en.wikipedia.org/wiki/Threonine","Name":"Threonine","Sub":false}]},{"Name":"DrugBank","Urls":[{"Link":"https://go.drugbank.com/DB00156","Name":"Threonine","Sub":false}]},{"Name":"PubChem","Urls":[{"Link":"https://pubchem.ncbi.nlm.nih.gov/compound/6288","Name":"Threonine","Sub":false}]},{"Name":"Common Chemistry","Urls":[{"Link":"https://commonchemistry.cas.org/detail?cas_rn=80-68-2","Name":"Threonine","Sub":false}]},{"Name":"HMDB","Urls":[{"Link":"https://hmdb.ca/metabolites/HMDB0000167","Name":"Threonine","Sub":false}]},{"Name":"KEGG","Urls":[{"Link":"https://www.kegg.jp/entry/C00188","Name":"Threonine","Sub":false}]},{"Name":"UNII","Urls":[{"Link":"https://gsrs.ncats.nih.gov/ginas/app/ui/substances/TFM6DU5S6A","Name":"Threonine","Sub":false}]},{"Name":"EPA DSSTox","Urls":[{"Link":"https://comptox.epa.gov/dashboard/chemical/details/DTXSID2046412","Name":"Threonine","Sub":false}]}],"Refs":["National Center for Biotechnology Information. PubChem Compound Summary for CID 6288, Threonine. Accessed June 13, 2026. \u003ca href=https://pubchem.ncbi.nlm.nih.gov/compound/6288\u003ehttps://pubchem.ncbi.nlm.nih.gov/compound/6288\u003c/a\u003e","U.S. Food and Drug Administration; National Center for Advancing Translational Sciences. Threonine. UNII: TFM6DU5S6A. Global Substance Registration System. Accessed June 13, 2026. \u003ca href=https://gsrs.ncats.nih.gov/ginas/app/beta/substances/TFM6DU5S6A\u003ehttps://gsrs.ncats.nih.gov/ginas/app/beta/substances/TFM6DU5S6A\u003c/a\u003e"],"SMILES":"C[C@H]([C@@H](C(=O)O)N)O","SaltData":[],"Salts":[],"Solubility":"Insoluble in ethanol, ethyl ether, chloroform","StereoisomerData":[],"Stereoisomers":[],"Structure":"\u003csvg xmlns=\"http://www.w3.org/2000/svg\" preserveAspectRatio=\"none\" style=\"display:block\" viewBox=\"0 0 61.154 45.84\"\u003e\u003crect width=\"100%\" height=\"100%\" fill=\"#fff\"/\u003e\u003cdesc\u003eGenerated by the Chemistry Development Kit (http://github.com/cdk)\u003c/desc\u003e\u003cg fill=\"#ff0d0d\" stroke=\"#000\" stroke-linecap=\"round\" stroke-linejoin=\"round\" stroke-width=\".8\"\u003e\u003cpath fill=\"#fff\" stroke=\"none\" d=\"M0 0h62v46H0z\"/\u003e\u003cg class=\"mol\"\u003e\u003cpath d=\"m1.106 26.013 13.199-7.62M14.305 18.393l13.198 7.62M27.503 26.013l13.198-7.62\" class=\"bond\"/\u003e\u003cg class=\"bond\"\u003e\u003cpath d=\"M39.482 19.096V7.345M41.92 19.096V7.345\"/\u003e\u003cpath stroke=\"#ff0d0d\" d=\"M39.482 7.345v5.875M41.92 7.345v5.875\" class=\"hi\"/\u003e\u003c/g\u003e\u003cpath d=\"m40.701 18.393 9.59 5.537\" class=\"bond\"/\u003e\u003cpath fill=\"#000\" stroke=\"none\" d=\"M27.903 26.013h-.8l-1.462 11.139h3.724zM13.905 18.393h.8l1.45-11.048h-3.7z\" class=\"bond\"/\u003e\u003cpath stroke=\"none\" d=\"M40.704 1.108q-.738 0-1.173.553-.428.548-.428 1.495 0 .946.428 1.494.435.547 1.173.547t1.167-.547q.429-.548.429-1.494 0-.947-.429-1.495-.429-.553-1.167-.553m0-.548q1.054 0 1.679.708.631.703.631 1.888 0 1.178-.631 1.887-.625.702-1.679.702t-1.685-.702q-.631-.703-.631-1.887t.631-1.888Q39.65.56 40.704.56\" class=\"atom\"/\u003e\u003cg stroke=\"none\" class=\"atom\"\u003e\u003cpath d=\"M53.902 23.968q-.738 0-1.172.553-.429.548-.429 1.495 0 .946.429 1.494.434.547 1.172.547.739 0 1.167-.547.429-.548.429-1.494 0-.947-.429-1.495-.428-.553-1.167-.553m0-.548q1.054 0 1.679.708.631.703.631 1.888 0 1.178-.631 1.887-.625.702-1.679.702-1.053 0-1.684-.702-.631-.703-.631-1.887t.631-1.888q.631-.708 1.684-.708M56.784 23.509h.678v2.048h2.459v-2.048h.673v5.001h-.673v-2.381h-2.459v2.381h-.678z\"/\u003e\u003c/g\u003e\u003cg fill=\"#3050f8\" stroke=\"none\" class=\"atom\"\u003e\u003cpath d=\"M25.61 38.752h.911l2.214 4.185v-4.185h.661v5.001h-.911l-2.22-4.185v4.185h-.655zM29.968 38.752h.678V40.8h2.459v-2.048h.673v5.001h-.673v-2.381h-2.459v2.381h-.678zM34.838 44.937h1.418v.343h-1.907v-.343q.232-.239.629-.639.4-.404.503-.522.197-.218.272-.368.078-.153.078-.3 0-.239-.168-.389-.167-.15-.435-.15-.193 0-.404.068-.211.064-.454.196v-.407q.247-.1.458-.15.214-.05.389-.05.468 0 .743.232.279.232.279.625 0 .182-.072.35-.068.165-.25.39-.05.057-.321.335-.268.279-.758.779\"/\u003e\u003c/g\u003e\u003cg stroke=\"none\" class=\"atom\"\u003e\u003cpath d=\"M14.308 1.108q-.739 0-1.173.553-.429.548-.429 1.495 0 .946.429 1.494.434.547 1.173.547.738 0 1.166-.547.429-.548.429-1.494 0-.947-.429-1.495-.428-.553-1.166-.553m0-.548q1.053 0 1.678.708.631.703.631 1.888 0 1.178-.631 1.887-.625.702-1.678.702-1.054 0-1.685-.702-.631-.703-.631-1.887t.631-1.888Q13.254.56 14.308.56M17.189.649h.679v2.048h2.458V.649h.673V5.65h-.673V3.269h-2.458V5.65h-.679z\"/\u003e\u003c/g\u003e\u003cpath stroke=\"#ff0d0d\" d=\"m50.291 23.93-4.795-2.768M50.291 23.93l-4.795-2.768\" class=\"hi\"/\u003e\u003c/g\u003e\u003c/g\u003e\u003c/svg\u003e","Therapeutic Uses":"L-threonine has been used clinically with the aim of increasing glycine concentrations in the cerebral spinal fluid of patients with spasticity. When given in amounts of 4.5 to 6.0 g/day for 14 days, no adverse clinical effects were noted in such patients.","Title":"Threonine","UNII":"TFM6DU5S6A","Violations":0,"Wikipedia":"Threonine","XLogP":-2.9}