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Record Information
StatusDetected and Quantified
Creation Date2005-11-16 15:48:42 UTC
Update Date2020-11-09 23:15:41 UTC
Secondary Accession Numbers
  • HMDB01451
Metabolite Identification
Common Name(R)-Lipoic acid
DescriptionLipoic acid is a vitamin-like antioxidant that acts as a free-radical scavenger. Alpha-lipoic acid is also known as thioctic acid. It is a naturally occurring compound that is synthesized by both plants and animals. Lipoic acid contains two thiol groups which may be either oxidized or reduced. The reduced form is known as dihydrolipoic acid (DHLA). Lipoic acid (Delta E= -0.288) is therefore capable of thiol-disulfide exchange, giving it antioxidant activity. Lipoate is a critical cofactor for aerobic metabolism, participating in the transfer of acyl or methylamine groups via the 2-Oxoacid dehydrogenase (2-OADH) or alpha-ketoglutarate dehydrogenase complex. This enzyme catalyzes the conversion of alpha-ketoglutarate to succinyl CoA. This activity results in the catabolism of the branched chain amino acids (leucine, isoleucine and valine). Lipoic acid also participates in the glycine cleavage system(GCV). The glycine cleavage system is a multi-enzyme complex that catalyzes the oxidation of glycine to form 5,10 methylene tetrahydrofolate, an important cofactor in nucleic acid synthesis. Since Lipoic acid is an essential cofactor for many enzyme complexes, it is essential for aerobic life as we know it. This system is used by many organisms and plays a crucial role in the photosynthetic carbon cycle. Lipoic acid was first postulated to be an effective antioxidant when it was found it prevented vitamin C and vitamin E deficiency. It is able to scavenge reactive oxygen species and reduce other metabolites, such as glutathione or vitamins, maintaining a healthy cellular redox state. Lipoic acid has been shown in cell culture experiments to increase cellular uptake of glucose by recruiting the glucose transporter GLUT4 to the cell membrane, suggesting its use in diabetes. Studies of rat aging have suggested that the use of L-carnitine and lipoic acid results in improved memory performance and delayed structural mitochondrial decay. As a result, it may be helpful for people with Alzheimer's disease or Parkinson's disease. -- Wikipedia .
(+)-alpha-Lipoic acidChEBI, HMDB
(R)-(+)-LipoateChEBI, KEGG
(R)-(+)-Lipoic acidChEBI, Generator
(R)-1,2-Dithiolane-3-pentanoic acidChEBI, HMDB
(R)-1,2-Dithiolane-3-valeric acidChEBI, HMDB
(R)-6,8-Thioctic acidChEBI, HMDB
alpha-Lipoic acidChEBI, HMDB
Lipoic acidChEBI, HMDB
R-(+)-Lipoic acidChEBI, KEGG
Thioctic acidChEBI, HMDB
Thioctic acid D-formChEBI, HMDB
(+)-a-LipoateGenerator, HMDB
(+)-a-Lipoic acidGenerator, HMDB
(+)-alpha-LipoateGenerator, HMDB
(+)-α-lipoateGenerator, HMDB
(+)-α-lipoic acidGenerator, HMDB
(R)-1,2-Dithiolane-3-pentanoateGenerator, HMDB
(R)-1,2-Dithiolane-3-valerateGenerator, HMDB
(R)-6,8-ThioctateGenerator, HMDB
a-LipoateGenerator, HMDB
a-Lipoic acidGenerator, HMDB
alpha-LipoateGenerator, HMDB
α-lipoateGenerator, HMDB
α-Lipoic acidGenerator, HMDB
LipoateGenerator, HMDB
ThioctateGenerator, HMDB
Thioctate D-formGenerator, HMDB
Acid, alpha-lipoicMeSH, HMDB
alpha Lipoic acidMeSH, HMDB
1,2-Dithiolane-3R-pentanoic acidKEGG
(R)-Lipoic acidKEGG
(3R)-1,2-Dithiolane-3-pentanoic acidHMDB
(R)-(+)-1,2-Dithiolane-3-pentanoic acidHMDB
(R)-(+)-alpha-Lipoic acidHMDB
(R)-(+)-α-Lipoic acidHMDB
(R)-alpha-Lipoic acidHMDB
(R)-α-Lipoic acidHMDB
alpha-(+)-Lipoic acidHMDB
α-(+)-Lipoic acidHMDB
1,2-Dithiolane-3-valeric acidHMDB
5-(1,2-Dithiolan-3-yl)pentanoic acidHMDB
5-(1,2-Dithiolan-3-yl)valeric acidHMDB
6,8-Thioctic acidHMDB
6-Thioctic acidHMDB
Chemical FormulaC8H14O2S2
Average Molecular Weight206.326
Monoisotopic Molecular Weight206.043521072
IUPAC Name5-[(3R)-1,2-dithiolan-3-yl]pentanoic acid
Traditional Namelipoic acid
CAS Registry Number1200-22-2
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as lipoic acids and derivatives. Lipoic acids and derivatives are compounds containing a lipoic acid moiety (or a derivative thereof), which consists of a pentanoic acid (or derivative) attached to the C3 carbon atom of a 1,2-dithiolane ring.
KingdomOrganic compounds
Super ClassOrganoheterocyclic compounds
Sub ClassLipoic acids and derivatives
Direct ParentLipoic acids and derivatives
Alternative Parents
  • Lipoic_acid_derivative
  • Medium-chain fatty acid
  • Heterocyclic fatty acid
  • Thia fatty acid
  • Fatty acyl
  • Fatty acid
  • 1,2-dithiolane
  • Organic disulfide
  • Monocarboxylic acid or derivatives
  • Carboxylic acid
  • Carboxylic acid derivative
  • Hydrocarbon derivative
  • Organooxygen compound
  • Organic oxide
  • Organic oxygen compound
  • Carbonyl group
  • Aliphatic heteromonocyclic compound
Molecular FrameworkAliphatic heteromonocyclic compounds
External Descriptors


Biological location:


Naturally occurring process:


Industrial application:

Physical Properties
Experimental Properties
Melting Point60.5 °CNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility0.22 g/LALOGPS
pKa (Strongest Acidic)4.52ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count2ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area37.3 ŲChemAxon
Rotatable Bond Count5ChemAxon
Refractivity54.37 m³·mol⁻¹ChemAxon
Polarizability21.74 ųChemAxon
Number of Rings1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleNoChemAxon
Spectrum TypeDescriptionSplash KeyView
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-0aba-3900000000-46fc1d57abcc26f6720eSpectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-0aba-3900000000-46fc1d57abcc26f6720eSpectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-0aba-3900000000-46fc1d57abcc26f6720eSpectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-0aba-3900000000-46fc1d57abcc26f6720eSpectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0ufu-5900000000-716655e029db4b97efd9Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positivesplash10-0hbi-6920000000-011fb15a0f9ca4513029Spectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-0a4r-0940000000-dead1b29e79e0002da2aSpectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-0f8c-9200000000-b6035bdb4abd0d267297Spectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-0059-9000000000-62e73cabbac1531f5145Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0a4i-1920000000-2b265e3ed116fbc0a2eaSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0ab9-2910000000-9142e84d978f4a481551Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0a4i-9200000000-8bdfe1c35977a8c80985Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0a4r-0940000000-6cecd351951f396a3035Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-08gr-6910000000-f169816d57d2290b0d9eSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0m2c-9700000000-57ae386a681b98208a4bSpectrum
1D NMR1H NMR SpectrumNot AvailableSpectrum
2D NMR[1H,13C] 2D NMR SpectrumNot AvailableSpectrum
Biological Properties
Cellular Locations
  • Cytoplasm
  • Extracellular
  • Membrane (predicted from logP)
Biospecimen Locations
  • Blood
  • Urine
Tissue Locations
  • Kidney
  • Liver
  • Neuron
  • Placenta
  • Skeletal Muscle
Normal Concentrations
BloodDetected but not QuantifiedNot QuantifiedAdult (>18 years old)BothNormal details
BloodDetected and Quantified0.077 +/- 0.017 uMAdult (>18 years old)BothNormal
    • Geigy Scientific ...
UrineDetected but not QuantifiedNot QuantifiedAdult (>18 years old)BothNormal details
Abnormal Concentrations
Not Available
Predicted Concentrations
BiospecimenValueOriginal ageOriginal sexOriginal conditionComments
Blood0.000 umol/mmol creatinineAdult (>18 years old)BothNormalPredicted based on drug qualities
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDDB00166
Phenol Explorer Compound IDNot Available
FooDB IDFDB022631
KNApSAcK IDC00000754
Chemspider ID5886
KEGG Compound IDC16241
BiGG ID35801
Wikipedia LinkLipoic_acid
PubChem Compound6112
PDB IDNot Available
ChEBI ID30314
Food Biomarker OntologyNot Available
MarkerDB ID
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Henriksen EJ, Saengsirisuwan V: Exercise training and antioxidants: relief from oxidative stress and insulin resistance. Exerc Sport Sci Rev. 2003 Apr;31(2):79-84. [PubMed:12715971 ]
  2. Arner ES, Nordberg J, Holmgren A: Efficient reduction of lipoamide and lipoic acid by mammalian thioredoxin reductase. Biochem Biophys Res Commun. 1996 Aug 5;225(1):268-74. [PubMed:8769129 ]
  3. Loginov AS, Nilova TV, Bendikov EA, Petrakov AV: [Pharmacokinetics of preparations of lipoic acid and their effect on ATP synthesis, processes of microsomal and cytosol oxidation in hepatocytes in liver damage in man]. Farmakol Toksikol. 1989 Jul-Aug;52(4):78-82. [PubMed:2509239 ]
  4. Baker H, Deangelis B, Baker ER, Hutner SH: A practical assay of lipoate in biologic fluids and liver in health and disease. Free Radic Biol Med. 1998 Sep;25(4-5):473-9. [PubMed:9741583 ]
  5. Konrad D: Utilization of the insulin-signaling network in the metabolic actions of alpha-lipoic acid-reduction or oxidation? Antioxid Redox Signal. 2005 Jul-Aug;7(7-8):1032-9. [PubMed:15998258 ]
  6. Bruggraber SF, Leung PS, Amano K, Quan C, Kurth MJ, Nantz MH, Benson GD, Van de Water J, Luketic V, Roche TE, Ansari AA, Coppel RL, Gershwin ME: Autoreactivity to lipoate and a conjugated form of lipoate in primary biliary cirrhosis. Gastroenterology. 2003 Dec;125(6):1705-13. [PubMed:14724823 ]
  7. Redden PR, Melanson RL, Douglas JA, Dick AJ: Acyloxymethyl acidic drug derivatives: in vitro hydrolytic reactivity. Int J Pharm. 1999 Apr 15;180(2):151-60. [PubMed:10370185 ]
  8. Tankova T, Cherninkova S, Koev D: Treatment for diabetic mononeuropathy with alpha-lipoic acid. Int J Clin Pract. 2005 Jun;59(6):645-50. [PubMed:15924591 ]
  9. Chevion S, Hofmann M, Ziegler R, Chevion M, Nawroth PP: The antioxidant properties of thioctic acid: characterization by cyclic voltammetry. Biochem Mol Biol Int. 1997 Feb;41(2):317-27. [PubMed:9063572 ]
  10. Barbiroli B, Medori R, Tritschler HJ, Klopstock T, Seibel P, Reichmann H, Iotti S, Lodi R, Zaniol P: Lipoic (thioctic) acid increases brain energy availability and skeletal muscle performance as shown by in vivo 31P-MRS in a patient with mitochondrial cytopathy. J Neurol. 1995 Jul;242(7):472-7. [PubMed:7595680 ]
  11. Burke DG, Chilibeck PD, Parise G, Tarnopolsky MA, Candow DG: Effect of alpha-lipoic acid combined with creatine monohydrate on human skeletal muscle creatine and phosphagen concentration. Int J Sport Nutr Exerc Metab. 2003 Sep;13(3):294-302. [PubMed:14669930 ]
  12. Teichert J, Tuemmers T, Achenbach H, Preiss C, Hermann R, Ruus P, Preiss R: Pharmacokinetics of alpha-lipoic acid in subjects with severe kidney damage and end-stage renal disease. J Clin Pharmacol. 2005 Mar;45(3):313-28. [PubMed:15703366 ]
  13. Haj-Yehia AI, Assaf P, Nassar T, Katzhendler J: Determination of lipoic acid and dihydrolipoic acid in human plasma and urine by high-performance liquid chromatography with fluorimetric detection. J Chromatogr A. 2000 Feb 18;870(1-2):381-8. [PubMed:10722093 ]
  14. Nagamatsu M, Nickander KK, Schmelzer JD, Raya A, Wittrock DA, Tritschler H, Low PA: Lipoic acid improves nerve blood flow, reduces oxidative stress, and improves distal nerve conduction in experimental diabetic neuropathy. Diabetes Care. 1995 Aug;18(8):1160-7. [PubMed:7587852 ]
  15. Steinmann B, Gitzelmann R: Strychnine treatment attempted in newborn twins with severe nonketotic hyperglycinemia. Helv Paediatr Acta. 1979;34(6):589-99. [PubMed:541222 ]
  16. Lee WJ, Lee IK, Kim HS, Kim YM, Koh EH, Won JC, Han SM, Kim MS, Jo I, Oh GT, Park IS, Youn JH, Park SW, Lee KU, Park JY: Alpha-lipoic acid prevents endothelial dysfunction in obese rats via activation of AMP-activated protein kinase. Arterioscler Thromb Vasc Biol. 2005 Dec;25(12):2488-94. Epub 2005 Oct 13. [PubMed:16224049 ]
  17. McCormick DB: A trail of research on cofactors: an odyssey with friends. J Nutr. 2000 Feb;130(2S Suppl):323S-330S. [PubMed:10721897 ]
  18. Semenova TV, Azhitskii GIu, Sarnatskaia VV, Nikolaev VG: [Effect of various specific agents on the heat stability of human serum albumin]. Ukr Biokhim Zh (1978). 1993 Sep-Oct;65(5):26-30. [PubMed:8160293 ]


General function:
Involved in acyltransferase activity
Specific function:
Required for anchoring dihydrolipoamide dehydrogenase (E3) to the dihydrolipoamide transacetylase (E2) core of the pyruvate dehydrogenase complexes of eukaryotes. This specific binding is essential for a functional PDH complex
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in acyltransferase activity
Specific function:
The pyruvate dehydrogenase complex catalyzes the overall conversion of pyruvate to acetyl-CoA and CO(2), and thereby links the glycolytic pathway to the tricarboxylic cycle.
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in oxidoreductase activity
Specific function:
This enzyme is required for electron transfer from NADP to cytochrome P450 in microsomes. It can also provide electron transfer to heme oxygenase and cytochrome B5.
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in acyltransferase activity
Specific function:
The 2-oxoglutarate dehydrogenase complex catalyzes the overall conversion of 2-oxoglutarate to succinyl-CoA and CO(2). It contains multiple copies of 3 enzymatic components: 2-oxoglutarate dehydrogenase (E1), dihydrolipoamide succinyltransferase (E2) and lipoamide dehydrogenase (E3).
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in glycine catabolic process
Specific function:
The glycine cleavage system catalyzes the degradation of glycine. The H protein shuttles the methylamine group of glycine from the P protein to the T protein.
Gene Name:
Uniprot ID:
Molecular weight:
Not Available
General function:
Involved in acyltransferase activity
Specific function:
The branched-chain alpha-keto dehydrogenase complex catalyzes the overall conversion of alpha-keto acids to acyl-CoA and CO(2). It contains multiple copies of three enzymatic components: branched-chain alpha-keto acid decarboxylase (E1), lipoamide acyltransferase (E2) and lipoamide dehydrogenase (E3).
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in catalytic activity
Specific function:
May play a role in the biosynthesis of lipoic acid as well as longer chain fatty acids required for optimal mitochondrial function.
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in catalytic activity
Specific function:
Catalyzes the transfer of the lipoyl group from lipoyl-AMP to the specific lysine residue of lipoyl domains of lipoate-dependent enzymes (By similarity).
Gene Name:
Uniprot ID:
Molecular weight: