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Record Information
StatusDetected but not Quantified
Creation Date2005-11-16 15:48:42 UTC
Update Date2018-05-19 23:09:43 UTC
Secondary Accession Numbers
  • HMDB0001963
  • HMDB00378
  • HMDB01963
Metabolite Identification
Common Name2-Methylbutyroylcarnitine
Description2-Methylbutyroylcarnitine is a member of the class of compounds known as acylcarnitines. Acylcarnitines are organic compounds containing a fatty acid with the carboxylic acid attached to carnitine through an ester bond. Thus, 2-Methylbutyroylcarnitine is considered to be a fatty ester lipid molecule. 2-Methylbutyroylcarnitine is practically insoluble (in water) and a weakly acidic compound (based on its pKa). 2-Methylbutyroylcarnitine can be found in urine. Within the cell, 2-Methylbutyroylcarnitine is primarily located in the membrane (predicted from logP). It can also be found in the extracellular space. Usually not detected in normal individuals, the elevation of 2-methylbutyrylcarnitine suggests a deficiency of a dehydrogenase specific for isobutyryl-CoA, important in the differential diagnosis of branched chain organic acidurias by analysis of urinary organic acids and acylcarnitines in plasma or dried blood spots (The Metabolic and Molecular Bases of Inherited Disease, Chapter 93).
3-[(2-Methylbutanoyl)oxy]-4-(trimethylammonio)butanoic acidGenerator
L-2-Methylbutyrate (3-carboxy-2-hydroxypropyl)trimethyl-hydroxide ammonium inner saltHMDB
Chemical FormulaC12H23NO4
Average Molecular Weight245.3153
Monoisotopic Molecular Weight245.162708229
IUPAC Name3-[(2-methylbutanoyl)oxy]-4-(trimethylazaniumyl)butanoate
Traditional Name2-methylbutyroylcarnitine
CAS Registry Number31023-25-3
InChI Identifier
Chemical Taxonomy
DescriptionThis compound belongs to the class of organic compounds known as acyl carnitines. These are organic compounds containing a fatty acid with the carboxylic acid attached to carnitine through an ester bond.
KingdomOrganic compounds
Super ClassLipids and lipid-like molecules
ClassFatty Acyls
Sub ClassFatty acid esters
Direct ParentAcyl carnitines
Alternative Parents
  • Acyl-carnitine
  • Branched fatty acid
  • Dicarboxylic acid or derivatives
  • Tetraalkylammonium salt
  • Quaternary ammonium salt
  • Carboxylic acid ester
  • Carboxylic acid salt
  • Carboxylic acid derivative
  • Carboxylic acid
  • Organonitrogen compound
  • Hydrocarbon derivative
  • Organic oxide
  • Organopnictogen compound
  • Organic nitrogen compound
  • Carbonyl group
  • Organic oxygen compound
  • Amine
  • Organooxygen compound
  • Organic salt
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External Descriptors

Route of exposure:


Biological location:


Naturally occurring process:


Industrial application:

Biological role:

Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility0.025 g/LALOGPS
pKa (Strongest Acidic)4.34ChemAxon
pKa (Strongest Basic)-7.1ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area66.43 ŲChemAxon
Rotatable Bond Count8ChemAxon
Refractivity86.44 m³·mol⁻¹ChemAxon
Polarizability26.51 ųChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash Key
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-000j-9470000000-b8dda6860bb724ab79a4View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-000i-9000000000-48dbfad44af00725715cView in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-000i-9000000000-5b6022070c8a2794e703View in MoNA
1D NMR1H NMR SpectrumNot AvailableView in JSpectraViewer
2D NMR[1H,13C] 2D NMR SpectrumNot AvailableView in JSpectraViewer
Biological Properties
Cellular Locations
  • Extracellular
  • Membrane
Biospecimen Locations
  • Urine
Tissue LocationsNot Available
Normal Concentrations
UrineDetected but not Quantified Adult (>18 years old)BothNormal details
Abnormal Concentrations
UrineDetected but not Quantified Adult (>18 years old)BothAutosomal dominant polycystic kidney disease (ADPKD) details
Associated Disorders and Diseases
Disease References
Autosomal dominant polycystic kidney disease
  1. Gronwald W, Klein MS, Zeltner R, Schulze BD, Reinhold SW, Deutschmann M, Immervoll AK, Boger CA, Banas B, Eckardt KU, Oefner PJ: Detection of autosomal dominant polycystic kidney disease by NMR spectroscopic fingerprinting of urine. Kidney Int. 2011 Jun;79(11):1244-53. doi: 10.1038/ki.2011.30. Epub 2011 Mar 9. [PubMed:21389975 ]
Associated OMIM IDs
  • 601313 (Autosomal dominant polycystic kidney disease)
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FoodDB IDFDB021996
KNApSAcK IDNot Available
Chemspider ID4932320
KEGG Compound IDNot Available
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkNot Available
PubChem Compound6426901
PDB IDNot Available
ChEBI ID73026
Synthesis ReferenceNakanishi, Toyofumi; Shimizu, Akira; Arimoto, Masao; Kanai, Michiko. Synthesis of acylcarnitines for differential diagnosis of metabolic disorders. Nippon Iyo Masu Supekutoru Gakkai Koenshu (1993), 18 129-32.
Material Safety Data Sheet (MSDS)Not Available
General References
  1. Kidouchi K, Niwa T, Nohara D, Asai K, Sugiyama N, Morishita H, Kobayashi M, Wada Y: Urinary acylcarnitines in a patient with neonatal multiple acyl-CoA dehydrogenation deficiency, quantified by a carboxylic acid analyzer with a reversed-phase column. Clin Chim Acta. 1988 Apr 29;173(3):263-72. [PubMed:3383426 ]
  2. Salamino F, Di Lisa F, Burlina AB, Menabo R, Barbato R, De Tullio R, Siliprandi N: Involvement of erythrocyte calpain in glycine- and carnitine-treated isovaleric acidemia. Pediatr Res. 1994 Aug;36(2):182-6. [PubMed:7970932 ]
  3. Abdenur JE, Chamoles NA, Guinle AE, Schenone AB, Fuertes AN: Diagnosis of isovaleric acidaemia by tandem mass spectrometry: false positive result due to pivaloylcarnitine in a newborn screening programme. J Inherit Metab Dis. 1998 Aug;21(6):624-30. [PubMed:9762597 ]
  4. Fries MH, Rinaldo P, Schmidt-Sommerfeld E, Jurecki E, Packman S: Isovaleric acidemia: response to a leucine load after three weeks of supplementation with glycine, L-carnitine, and combined glycine-carnitine therapy. J Pediatr. 1996 Sep;129(3):449-52. [PubMed:8804338 ]
  5. Millington DS, Roe CR, Maltby DA, Inoue F: Endogenous catabolism is the major source of toxic metabolites in isovaleric acidemia. J Pediatr. 1987 Jan;110(1):56-60. [PubMed:3794887 ]
  6. Minkler PE, Ingalls ST, Hoppel CL: High-performance liquid chromatographic separation of acylcarnitines following derivatization with 4'-bromophenacyl trifluoromethanesulfonate. Anal Biochem. 1990 Feb 15;185(1):29-35. [PubMed:2344045 ]
  7. Chalmers RA, Roe CR, Stacey TE, Hoppel CL: Urinary excretion of l-carnitine and acylcarnitines by patients with disorders of organic acid metabolism: evidence for secondary insufficiency of l-carnitine. Pediatr Res. 1984 Dec;18(12):1325-8. [PubMed:6441143 ]
  8. Roe CR, Millington DS, Maltby DA, Kahler SG, Bohan TP: L-carnitine therapy in isovaleric acidemia. J Clin Invest. 1984 Dec;74(6):2290-5. [PubMed:6549017 ]
  9. Roe CR, Cederbaum SD, Roe DS, Mardach R, Galindo A, Sweetman L: Isolated isobutyryl-CoA dehydrogenase deficiency: an unrecognized defect in human valine metabolism. Mol Genet Metab. 1998 Dec;65(4):264-71. [PubMed:9889013 ]
  10. Sakuma T, Sugiyama N, Ichiki T, Kobayashi M, Wada Y, Nohara D: Analysis of acylcarnitines in maternal urine for prenatal diagnosis of glutaric aciduria type 2. Prenat Diagn. 1991 Feb;11(2):77-82. [PubMed:2062823 ]
  11. Matern D, He M, Berry SA, Rinaldo P, Whitley CB, Madsen PP, van Calcar SC, Lussky RC, Andresen BS, Wolff JA, Vockley J: Prospective diagnosis of 2-methylbutyryl-CoA dehydrogenase deficiency in the Hmong population by newborn screening using tandem mass spectrometry. Pediatrics. 2003 Jul;112(1 Pt 1):74-8. [PubMed:12837870 ]
  12. Pontremoli S, Melloni E, Michetti M, Sparatore B, Salamino F, Siliprandi N, Horecker BL: Isovalerylcarnitine is a specific activator of calpain of human neutrophils. Biochem Biophys Res Commun. 1987 Nov 13;148(3):1189-95. [PubMed:2825678 ]
  13. Ferrara F, Bertelli A, Falchi M: Evaluation of carnitine, acetylcarnitine and isovalerylcarnitine on immune function and apoptosis. Drugs Exp Clin Res. 2005;31(3):109-14. [PubMed:16033249 ]
  14. Bene J, Komlosi K, Havasi V, Talian G, Gasztonyi B, Horvath K, Mozsik G, Hunyady B, Melegh B, Figler M: Changes of plasma fasting carnitine ester profile in patients with ulcerative colitis. World J Gastroenterol. 2006 Jan 7;12(1):110-3. [PubMed:16440427 ]
  15. Fontaine M, Briand G, Vallee L, Ricart G, Degand P, Divry P, Vianey-Saban C, Vamecq J: Acylcarnitine removal in a patient with acyl-CoA beta-oxidation deficiency disorder: effect of L-carnitine therapy and starvation. Clin Chim Acta. 1996 Aug 30;252(2):109-22. [PubMed:8853559 ]
  16. Shigematsu Y, Kikawa Y, Sudo M, Kanaoka H, Fujioka M, Dan M: Prenatal diagnosis of isovaleric acidemia by fast atom bombardment and tandem mass spectrometry. Clin Chim Acta. 1991 Dec 16;203(2-3):369-74. [PubMed:1777996 ]