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Record Information
StatusDetected but not Quantified
Creation Date2006-05-22 15:12:50 UTC
Update Date2020-02-26 21:24:29 UTC
Secondary Accession Numbers
  • HMDB03320
Metabolite Identification
Common NameIndole-3-carboxylic acid
DescriptionIndole-3-carboxylic acid, also known as 3-carboxyindole or 3-indolecarboxylate, belongs to the class of organic compounds known as indolecarboxylic acids and derivatives. Indolecarboxylic acids and derivatives are compounds containing a carboxylic acid group (or a derivative thereof) linked to an indole. Naphthylmethylindoles: Any compound containing a 1H-indol-3-yl-(1-naphthyl)methane structure with substitution at the nitrogen atom of the indole ring by an alkyl, haloalkyl, alkenyl, cycloalkylmethyl, cycloalkylethyl, 1-(N-methyl-2-piperidinyl)methyl, or 2-(4-morpholinyl)ethyl group whether or not further substituted in the indole ring to any extent and whether or not substituted in the naphthyl ring to any extent. Indole-3-carboxylic acid is a weakly acidic compound (based on its pKa). One example given is JWH-250. Outside of the human body, indole-3-carboxylic acid has been detected, but not quantified in, several different foods, such as brassicas, broccoli, pulses, common beets, and barley. This could make indole-3-carboxylic acid a potential biomarker for the consumption of these foods. Notice the pentyl group substituted onto the nitrogen atom of the indole ring. Note that this definition encompasses only those compounds that have OH groups attached to both the phenyl and the cyclohexyl rings, and so does not include compounds such as O-1871 which lacks the cyclohexyl OH group, or compounds such as JWH-337 or JWH-344 which lack the phenolic OH group.
1H-Indole-3-carboxylic acidHMDB
3-Indole carboxylic acidHMDB
3-Indolecarboxylic acidHMDB
3-Indoleformic acidHMDB
3-Indolylcarboxylic acidHMDB
Indole - 3 carboxylateHMDB
Indole - 3 carboxylic acidHMDB
Indole-3-carboxylic acidKEGG
Chemical FormulaC9H7NO2
Average Molecular Weight161.1574
Monoisotopic Molecular Weight161.047678473
IUPAC Name1H-indole-3-carboxylic acid
Traditional Nameindole - 3 carboxylic acid
CAS Registry Number771-50-6
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as indolecarboxylic acids and derivatives. Indolecarboxylic acids and derivatives are compounds containing a carboxylic acid group (or a derivative thereof) linked to an indole.
KingdomOrganic compounds
Super ClassOrganoheterocyclic compounds
ClassIndoles and derivatives
Sub ClassIndolecarboxylic acids and derivatives
Direct ParentIndolecarboxylic acids and derivatives
Alternative Parents
  • Indolecarboxylic acid derivative
  • Indole
  • Pyrrole-3-carboxylic acid
  • Pyrrole-3-carboxylic acid or derivatives
  • Substituted pyrrole
  • Benzenoid
  • Pyrrole
  • Heteroaromatic compound
  • Vinylogous amide
  • Monocarboxylic acid or derivatives
  • Carboxylic acid derivative
  • Carboxylic acid
  • Azacycle
  • Hydrocarbon derivative
  • Organic oxide
  • Organopnictogen compound
  • Organooxygen compound
  • Organonitrogen compound
  • Organic oxygen compound
  • Organic nitrogen compound
  • Aromatic heteropolycyclic compound
Molecular FrameworkAromatic heteropolycyclic compounds
External Descriptors

Route of exposure:


Biological location:

Physical Properties
Experimental Properties
Melting Point206.5 °CNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogP1.99HANSCH,C ET AL. (1995)
Predicted Properties
Water Solubility2.42 g/LALOGPS
pKa (Strongest Acidic)3.52ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count2ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area53.09 ŲChemAxon
Rotatable Bond Count1ChemAxon
Refractivity44.4 m³·mol⁻¹ChemAxon
Polarizability15.96 ųChemAxon
Number of Rings2ChemAxon
Rule of FiveYesChemAxon
Ghose FilterNoChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Spectrum TypeDescriptionSplash KeyView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-03xu-0900000000-cc599488e0b8dc7f1a65Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positivesplash10-00xu-9640000000-dff74635f047e367f224Spectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-03di-0900000000-104208fcdd8732ebadf0Spectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-014l-4900000000-6b0c749e944b64d5385cSpectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-014u-9300000000-0af5d90221e77a572181Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF (UPLC Q-Tof Premier, Waters) , Negativesplash10-014i-0900000000-8c45f845ef01c19b445cSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF (UPLC Q-Tof Premier, Waters) , Positivesplash10-014l-1900000000-1c77378b797771275320Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-qToF , Positivesplash10-0udi-0900000000-946741c676c658f5309fSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , negativesplash10-014i-0900000000-8c45f845ef01c19b445cSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-02t9-0900000000-6053c6788a142676471bSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-014l-1900000000-1995f9dbe32f987d490aSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-014l-9800000000-670cc23cba665a2c274cSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-00ko-9100000000-933c5733f214b898f898Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-03xu-0900000000-3f9d7c7294f2ea5a6c2cSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-014l-0900000000-a2251627ca78c6acb131Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-014l-0900000000-391c26d59d3501f7004cSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-014i-0900000000-9af372afcef18a3b9f32Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-014i-0900000000-265f90afc22f3879b03eSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-014i-0900000000-3e251a670db5df960fd6Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-014i-0900000000-ff43090393a4f119b73aSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-014l-1900000000-1c77378b797771275320Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-03dl-0900000000-bac7fe6d41164b57962aSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0006-0900000000-75aeec0d90802e4f4ce6Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0006-0900000000-4057c3f38ac935f3f96bSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-02t9-0900000000-92711ed9a44b0be75d6bSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-014i-0900000000-4f69556e7cb4da6b44d3Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-014i-0900000000-c48621befefcf6da4d50Spectrum
1D NMR1H NMR SpectrumNot AvailableSpectrum
2D NMR[1H,13C] 2D NMR SpectrumNot AvailableSpectrum
Biological Properties
Cellular LocationsNot Available
Biospecimen Locations
  • Feces
Tissue LocationsNot Available
Normal Concentrations
FecesDetected but not QuantifiedNot QuantifiedAdult (>18 years old)Both
FecesDetected but not QuantifiedNot QuantifiedAdult (>18 years old)Both
FecesDetected but not QuantifiedNot QuantifiedAdult (>18 years old)Both
Abnormal Concentrations
FecesDetected but not QuantifiedNot QuantifiedAdult (>18 years old)Both
Metastatic melanoma
FecesDetected but not QuantifiedNot QuantifiedAdult (>18 years old)Both
Colorectal cancer
FecesDetected but not QuantifiedNot QuantifiedAdult (>18 years old)BothColorectal Cancer details
Associated Disorders and Diseases
Disease References
Colorectal cancer
  1. Brown DG, Rao S, Weir TL, O'Malia J, Bazan M, Brown RJ, Ryan EP: Metabolomics and metabolic pathway networks from human colorectal cancers, adjacent mucosa, and stool. Cancer Metab. 2016 Jun 6;4:11. doi: 10.1186/s40170-016-0151-y. eCollection 2016. [PubMed:27275383 ]
  2. Goedert JJ, Sampson JN, Moore SC, Xiao Q, Xiong X, Hayes RB, Ahn J, Shi J, Sinha R: Fecal metabolomics: assay performance and association with colorectal cancer. Carcinogenesis. 2014 Sep;35(9):2089-96. doi: 10.1093/carcin/bgu131. Epub 2014 Jul 18. [PubMed:25037050 ]
Metastatic melanoma
  1. Frankel AE, Coughlin LA, Kim J, Froehlich TW, Xie Y, Frenkel EP, Koh AY: Metagenomic Shotgun Sequencing and Unbiased Metabolomic Profiling Identify Specific Human Gut Microbiota and Metabolites Associated with Immune Checkpoint Therapy Efficacy in Melanoma Patients. Neoplasia. 2017 Oct;19(10):848-855. doi: 10.1016/j.neo.2017.08.004. Epub 2017 Sep 15. [PubMed:28923537 ]
Associated OMIM IDs
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FooDB IDFDB000935
KNApSAcK IDC00000113
Chemspider ID63063
KEGG Compound IDC19837
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkStructural scheduling of synthetic cannabinoids
PubChem Compound69867
PDB IDNot Available
ChEBI ID24809
Food Biomarker OntologyNot Available
VMH IDNot Available
MarkerDB ID
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Liebich HM, Forst C: Basic profiles of organic acids in urine. J Chromatogr. 1990 Jan 26;525(1):1-14. [PubMed:2338430 ]
  2. HARTMANN F, FREIBERG E, RUGE W: [Indolepatterns in the urine of liver patients]. Klin Wochenschr. 1962 Jul 15;40:721-9. [PubMed:13905029 ]
  3. Byrd DJ, Kochen W, Idzko D, Knorr E: The analysis of indolic tryptophan metabolites in human urine. Thin-layer chromatography and in situ quantitation. J Chromatogr. 1974 Jul 17;94(0):85-106. [PubMed:4844607 ]


General function:
Involved in transferase activity, transferring hexosyl groups
Specific function:
UDPGT is of major importance in the conjugation and subsequent elimination of potentially toxic xenobiotics and endogenous compounds. This isoform glucuronidates bilirubin IX-alpha to form both the IX-alpha-C8 and IX-alpha-C12 monoconjugates and diconjugate. Is also able to catalyze the glucuronidation of 17beta-estradiol, 17alpha-ethinylestradiol, 1-hydroxypyrene, 4-methylumbelliferone, 1-naphthol, paranitrophenol, scopoletin, and umbelliferone.
Gene Name:
Uniprot ID:
Molecular weight:
Indole-3-carboxylic acid → 3,4,5-trihydroxy-6-(1H-indole-3-carbonyloxy)oxane-2-carboxylic aciddetails
General function:
Involved in glycine N-acyltransferase activity
Specific function:
Mitochondrial acyltransferase which transfers an acyl group to the N-terminus of glycine and glutamine, although much less efficiently. Can conjugate numerous substrates to form a variety of N-acylglycines, with a preference for benzoyl-CoA over phenylacetyl-CoA as acyl donors. Thereby detoxify xenobiotics, such as benzoic acid or salicylic acid, and endogenous organic acids, such as isovaleric acid.
Gene Name:
Uniprot ID:
Molecular weight:
Indole-3-carboxylic acid → 2-{[hydroxy(1H-indol-3-yl)methylidene]amino}acetic aciddetails