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Record Information
StatusDetected and Quantified
Creation Date2006-05-22 15:12:12 UTC
Update Date2017-12-07 01:54:37 UTC
Secondary Accession Numbers
  • HMDB04988
Metabolite Identification
Common NamePi-Methylimidazoleacetic acid
DescriptionPi-methylimidazoleacetic acid, also known as 1-methyl-imidazole-5-acetate or P-miaa, belongs to imidazolyl carboxylic acids and derivatives class of compounds. Those are organic compounds containing a carboxylic acid chain (of at least 2 carbon atoms) linked to an imidazole ring. Pi-methylimidazoleacetic acid is slightly soluble (in water) and a weakly acidic compound (based on its pKa). Pi-methylimidazoleacetic acid can be found primarily in blood, cerebrospinal fluid (CSF), and urine, as well as in human brain tissue. Within the cell, pi-methylimidazoleacetic acid is primarily located in the cytoplasm (predicted from logP). Although pi-Methylimidazoleacetic acid's isomer (1,4-Methylimidazoleacetic acid) is a known metabolite of Histamine, the origin of N pi-methylimidazoleacetic acid is not certain (PMID 7130180 )..
1-Methyl-imidazole-5-acetic acidChEBI
pros-Methylimidazoleacetic acidChEBI
1-Methyl-5-imidazoleacetic acidHMDB
Chemical FormulaC6H8N2O2
Average Molecular Weight140.1399
Monoisotopic Molecular Weight140.05857751
IUPAC Name2-(1-methyl-1H-imidazol-5-yl)acetic acid
Traditional NameP-miaa
CAS Registry Number4200-48-0
InChI Identifier
Chemical Taxonomy
DescriptionThis compound belongs to the class of organic compounds known as imidazolyl carboxylic acids and derivatives. These are organic compounds containing a carboxylic acid chain (of at least 2 carbon atoms) linked to an imidazole ring.
KingdomOrganic compounds
Super ClassOrganoheterocyclic compounds
Sub ClassImidazoles
Direct ParentImidazolyl carboxylic acids and derivatives
Alternative Parents
  • Imidazolyl carboxylic acid derivative
  • N-substituted imidazole
  • Heteroaromatic compound
  • Carboxylic acid derivative
  • Carboxylic acid
  • Monocarboxylic acid or derivatives
  • Azacycle
  • Carbonyl group
  • Organooxygen compound
  • Organonitrogen compound
  • Hydrocarbon derivative
  • Organic oxide
  • Organopnictogen compound
  • Organic oxygen compound
  • Organic nitrogen compound
  • Aromatic heteromonocyclic compound
Molecular FrameworkAromatic heteromonocyclic compounds
External Descriptors
  • Endogenous
  • Protein synthesis, amino acid biosynthesis
ApplicationNot Available
Cellular locations
  • Cytoplasm (predicted from logP)
Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility5.89 g/LALOGPS
pKa (Strongest Acidic)3.81ChemAxon
pKa (Strongest Basic)6.63ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area55.12 ŲChemAxon
Rotatable Bond Count2ChemAxon
Refractivity35.09 m³·mol⁻¹ChemAxon
Polarizability13.38 ųChemAxon
Number of Rings1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash Key
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0005-9400000000-03c4a0f73e55903dba95View in MoNA
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positivesplash10-009b-9200000000-7ced1cd26056a3e5788cView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-006x-0900000000-c71712049d7a61a77210View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-00dl-2900000000-1ecc98b5be58e80b8b90View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0jca-9200000000-f020fb0ff4ee468b3cd9View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-000i-3900000000-5a1f08ae8e10686a8019View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-000j-8900000000-fed7fbafe3182a1f7952View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-00b9-9300000000-7a7de3567ca8cd3454ebView in MoNA
Biological Properties
Cellular Locations
  • Cytoplasm (predicted from logP)
Biofluid Locations
  • Blood
  • Cerebrospinal Fluid (CSF)
  • Urine
Tissue Location
  • Brain
PathwaysNot Available
Normal Concentrations
BloodDetected and Quantified0.073 +/- 0.014 uMAdult (>18 years old)Not SpecifiedNormal details
Cerebrospinal Fluid (CSF)Detected and Quantified0.08 +/- 0.018 uMAdult (>18 years old)Not SpecifiedNormal details
UrineDetected and Quantified1.131 (0.170-2.149) umol/mmol creatinineAdult (>18 years old)BothNormal details
UrineDetected and Quantified1.7 (0.26-3.35) umol/mmol creatinineAdult (>18 years old)BothNormal
    • Geigy Scientific ...
UrineDetected and Quantified8.25 +/- 4.3 umol/mmol creatinineAdult (>18 years old)BothNormal details
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FoodDB IDFDB023572
KNApSAcK IDNot Available
Chemspider ID4954265
KEGG Compound IDNot Available
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkNot Available
PubChem Compound6451814
PDB IDNot Available
ChEBI ID70966
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General References
  1. Tsuruta Y, Tomida H, Kohashi K, Ohkura Y: Simultaneous determination of imidazoleacetic acid and N tau- and N pi-methylimidazoleacetic acids in human urine by high-performance liquid chromatography with fluorescence detection. J Chromatogr. 1987 Apr 24;416(1):63-9. [PubMed:3597642 ]
  2. Khandelwal JK, Hough LB, Pazhenchevsky B, Morrishow AM, Green JP: Presence and measurement of methylimidazoleacetic acids in brain and body fluids. J Biol Chem. 1982 Nov 10;257(21):12815-9. [PubMed:7130180 ]
  3. Yocum MW, Butterfield JH, Gharib H: Increased plasma calcitonin levels in systemic mast cell disease. Mayo Clin Proc. 1994 Oct;69(10):987-90. [PubMed:7934197 ]
  4. Prell GD, Green JP, Kaufmann CA, Khandelwal JK, Morrishow AM, Kirch DG, Linnoila M, Wyatt RJ: Histamine metabolites in cerebrospinal fluid of patients with chronic schizophrenia: their relationships to levels of other aminergic transmitters and ratings of symptoms. Schizophr Res. 1995 Jan;14(2):93-104. [PubMed:7711000 ]
  5. Granerus G, Roupe G, Swanbeck G: Decreased urinary histamine metabolite after successful PUVA treatment of urticaria pigmentosa. J Invest Dermatol. 1981 Jan;76(1):1-3. [PubMed:7462662 ]