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Record Information
Creation Date2005-11-16 15:48:42 UTC
Update Date2016-02-11 01:02:13 UTC
Secondary Accession Numbers
  • HMDB01237
  • HMDB31629
Metabolite Identification
Common NamePhenylpyruvic acid
DescriptionPhenylpyruvic acid is a keto-acid that is an intermediate or catabolic byproduct of phenylalanine metabolism. It has a slight honey-like odor. Levels of phenylpyruvate are normally very low in blood or urine. High levels of phenylpyruvic acid can be found in the urine of individuals with phenylketonuria (PKU). PKU is due to lack of the enzyme phenylalanine hydroxylase (PAH), so that phenylalanine is converted not to tyrosine but to phenylpyruvic acid. In particular, excessive phenylalanine can be metabolized into phenylketones through, a transaminase pathway route involving glutamate. Metabolites of this transamination reaction include phenylacetate, phenylpyruvate and phenethylamine. In persons with PKU, dietary phenylalanine either accumulates in the body or some of it is converted to phenylpyruvic acid. Individuals with PKU tend to excrete large quantities of phenylpyruvate, phenylacetate and phenyllactate, along with phenylalanine, in their urine. If untreated, mental retardation effects and microcephaly are evident by the first year along with other symptoms which include: unusual irritability, epileptic seizures and skin lesions. Hyperactivity, EEG abnormalities and seizures, and severe learning disabilities are major clinical problems later in life. A "musty or mousy" odor of skin, hair, sweat and urine (due to phenylacetate accumulation); and a tendency to hypopigmentation and eczema are also observed. The neural-development effects of PKU are primarily due to the disruption of neurotransmitter synthesis. In particular, phenylalanine is a large, neutral amino acid which moves across the blood-brain barrier (BBB) via the large neutral amino acid transporter (LNAAT). Excessive phenylalanine in the blood saturates the transporter. Thus, excessive levels of phenylalanine significantly decrease the levels of other LNAAs in the brain. But since these amino acids are required for protein and neurotransmitter synthesis, phenylalanine accumulation disrupts brain development, leading to mental retardation.
  1. 2-Hydroxy-3-phenyl-2-propenoic acid, 9CI
  2. 2-Oxo-3-phenylpropanoate
  3. 2-Oxo-3-phenylpropanoic acid
  4. 2-Oxo-3-phenylpropanoic acid (Mixture oxo and keto)
  5. 3-Phenyl-2-oxopropanoate
  6. 3-Phenyl-2-oxopropanoic acid
  7. 3-Phenylpyruvate
  8. 3-Phenylpyruvic acid
  9. a-Hydroxycinnamic acid
  10. a-Oxobenzenepropanoic acid, 9CI
  11. alpha-Ketohydrocinnamate
  12. alpha-Ketohydrocinnamic acid
  13. b-Phenylpyruvate
  14. b-Phenylpyruvic acid
  15. beta-Phenylpyruvate
  16. beta-Phenylpyruvic acid
  17. FEMA 3892
  18. Keto-Phenylpyruvate
  19. Phenylpyroracemate
  20. Phenylpyroracemic acid
  21. Phenylpyruvate
Chemical FormulaC9H8O3
Average Molecular Weight164.158
Monoisotopic Molecular Weight164.047344122
IUPAC Name2-oxo-3-phenylpropanoic acid
Traditional Namephenylpyruvic acid
CAS Registry Number156-06-9
InChI Identifier
Chemical Taxonomy
DescriptionThis compound belongs to the class of organic compounds known as phenylpyruvic acid derivatives. These are compounds containing a phenylpyruvic acid moiety, which consists of a phenyl group substituted at the second position by an pyruvic acid.
KingdomOrganic compounds
Super ClassBenzenoids
ClassBenzene and substituted derivatives
Sub ClassPhenylpyruvic acid derivatives
Direct ParentPhenylpyruvic acid derivatives
Alternative Parents
  • Phenylpyruvate
  • 3-phenylpropanoic-acid
  • Keto acid
  • Alpha-keto acid
  • Alpha-hydroxy ketone
  • Ketone
  • Monocarboxylic acid or derivatives
  • Carboxylic acid
  • Carboxylic acid derivative
  • Hydrocarbon derivative
  • Organooxygen compound
  • Carbonyl group
  • Aromatic homomonocyclic compound
Molecular FrameworkAromatic homomonocyclic compounds
External Descriptors
StatusDetected and Quantified
  • Endogenous
  • Microbial
  • Component of Novobiocin biosynthesis
  • Component of Phenylalanine metabolism
  • Component of Phenylalanine, tyrosine and tryptophan biosynthesis
  • Component of Tyrosine metabolism
  • Flavoring Agent
Cellular locations
  • Cytoplasm
  • Mitochondria
Physical Properties
Experimental Properties
Melting Point154 °CNot Available
Boiling PointNot AvailableNot Available
Water Solubility112 mg/mLNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility0.93 mg/mLALOGPS
pKa (Strongest Acidic)3.33ChemAxon
pKa (Strongest Basic)-9.8ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area54.37 Å2ChemAxon
Rotatable Bond Count3ChemAxon
Refractivity42.71 m3·mol-1ChemAxon
Polarizability15.75 Å3ChemAxon
Number of Rings1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash Key
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (1 TMS)splash10-zs20000000-1a891469df1de787159bView in MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies)splash10-7z00000000-7dc1a5344d13e4dc19acView in MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies)splash10-1z00000000-bbbc84c54d03c4a14e51View in MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies)splash10-0z00000000-00b547b0371603520b61View in MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (1 TMS; 1 MEOX)splash10-z700000000-fdd48b632e63c8478078View in MoNA
GC-MSGC-MS Spectrum - GC-MS (1 MEOX; 1 TMS)splash10-ze00000000-8cd32f87e04ae0b6d6fbView in MoNA
GC-MSGC-MS Spectrum - GC-MS (1 MEOX; 1 TMS)splash10-zu80000000-7a0b66e6c18ff42ac05eView in MoNA
GC-MSGC-MS Spectrum - GC-MS (2 TMS)splash10-ztn1000000-d94111a7b9babceb265bView in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-0z00000000-ceb2ce23352e0f45ee33View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-z800000000-ed4a6740d574858da982View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-z000000000-c239a9a599daa607e47fView in MoNA
MSMass Spectrum (Electron Ionization)splash10-zc00000000-d1a7d23e7c5270b16883View in MoNA
1D NMR1H NMR SpectrumNot Available
2D NMR[1H,13C] 2D NMR SpectrumNot Available
Biological Properties
Cellular Locations
  • Cytoplasm
  • Mitochondria
Biofluid Locations
  • Blood
  • Urine
Tissue LocationNot Available
Phenylalanine and Tyrosine MetabolismSMP00008map00360
PhenylketonuriaSMP00206Not Available
Tyrosinemia Type 2 (or Richner-Hanhart syndrome)SMP00369Not Available
Tyrosinemia Type 3 (TYRO3)SMP00370Not Available
Normal Concentrations
BloodDetected and Quantified0.5 +/- 0.1 uMAdult (>18 years old)BothNormal details
UrineDetected and Quantified0.17 (0.05-0.67) umol/mmol creatinineAdult (>18 years old)MaleNormal details
UrineDetected and Quantified0.24 (0.10-0.76) umol/mmol creatinineAdult (>18 years old)FemaleNormal details
UrineDetected and Quantified<2 umol/mmol creatinineChildren (1 - 18 years old)Both
    • BC Children's Hos...
UrineDetected and Quantified0.25 +/- 0.43 umol/mmol creatinineInfant (0-1 year old)BothNormal details
Abnormal Concentrations
BloodDetected and Quantified50.0 (40.0-60.0) uMNewborn (0-30 days old)BothPhenylketonuria details
BloodDetected and Quantified1.4 +/- 0.2 uMAdult (>18 years old)BothPrimary biliary cirrhosis details
UrineDetected and Quantified2.00 (0.00-4.00) umol/mmol creatinineAdult (>18 years old)BothPhenylketonuria details
UrineDetected and Quantified650.00 (300.00-1000.00) umol/mmol creatinineNewborn (0-30 days old)BothPhenylketonuria details
UrineDetected and Quantified146.6 +/- 244.6 umol/mmol creatinineNewborn (0-30 days old)BothPhenylketonuria details
Associated Disorders and Diseases
Disease References
  1. Langenbeck U, Behbehani A, Luthe H: Renal transport of aromatic acids in patients with phenylketonuria. J Inherit Metab Dis. 1981;4(2):69-70. [6790852 ]
  2. Monch E, Kneer J, Jakobs C, Arnold M, Diehl H, Batzler U: Examination of urine metabolites in the newborn period and during protein loading tests at 6 months of age--Part 1. Eur J Pediatr. 1990;149 Suppl 1:S17-24. [2091926 ]
  3. MetaGene [Link]
Primary biliary cirrhosis
  1. Turchany JM, Leung PS, Iwayama T, Jefferson DM, Ishida J, Yamaguchi M, Munoz S, Danner DJ, Dickson ER, Gershwin ME: Comparative metabolism and structure of BCKD-E2 in primary biliary cirrhosis. J Autoimmun. 1993 Aug;6(4):459-66. [8216688 ]
Associated OMIM IDs
DrugBank IDNot Available
DrugBank Metabolite IDNot Available
Phenol Explorer Compound IDNot Available
Phenol Explorer Metabolite IDNot Available
FoodDB IDFDB020197
KNApSAcK IDC00000751
Chemspider ID972
KEGG Compound IDC00166
BiGG ID34111
Wikipedia LinkNot Available
NuGOwiki LinkHMDB00205
Metagene LinkHMDB00205
PubChem Compound997
ChEBI ID30851
Synthesis ReferenceLi, Hongbin; Luo, Yuzhong. Preparation of phenyl-pyruvic acid by dicarbonylation of benzyl halide. Faming Zhuanli Shenqing Gongkai Shuomingshu (1996), 5 pp.
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Shoemaker JD, Elliott WH: Automated screening of urine samples for carbohydrates, organic and amino acids after treatment with urease. J Chromatogr. 1991 Jan 2;562(1-2):125-38. [2026685 ]
  2. Lee SH, Kim SO, Chung BC: Gas chromatographic-mass spectrometric determination of urinary oxoacids using O-(2,3,4,5,6-pentafluorobenzyl)oxime-trimethylsilyl ester derivatization and cation-exchange chromatography. J Chromatogr B Biomed Sci Appl. 1998 Nov 20;719(1-2):1-7. [9869358 ]
  3. Boulat O, Gradwohl M, Matos V, Guignard JP, Bachmann C: Organic acids in the second morning urine in a healthy Swiss paediatric population. Clin Chem Lab Med. 2003 Dec;41(12):1642-58. [14708889 ]
  4. Lasala JM, Coscia CJ: Accumulation of a tetrahydroisoquinoline in phenylketonuria. Science. 1979 Jan 19;203(4377):283-4. [153583 ]
  5. Cassidei L, Dell'atti A, Sciacovelli O: Improvement of the FeCl3 test for phenylpyruvic acid. Clin Chim Acta. 1978 Dec 1;90(2):121-7. [719897 ]
  6. Michals K, Matalon R: Phenylalanine metabolites, attention span and hyperactivity. Am J Clin Nutr. 1985 Aug;42(2):361-5. [4025205 ]
  7. Nakahara T, Ishida J, Yamaguchi M, Nakamura M: Determination of alpha-keto acids including phenylpyruvic acid in human plasma by high-performance liquid chromatography with chemiluminescence detection. Anal Biochem. 1990 Nov 1;190(2):309-13. [2291475 ]
  8. Yannai, Shmuel. (2004) Dictionary of food compounds with CD-ROM: Additives, flavors, and ingredients. Boca Raton: Chapman & Hall/CRC.


General function:
Involved in cell surface binding
Specific function:
Pro-inflammatory cytokine. Involved in the innate immune response to bacterial pathogens. The expression of MIF at sites of inflammation suggests a role as mediator in regulating the function of macrophages in host defense. Counteracts the anti-inflammatory activity of glucocorticoids. Has phenylpyruvate tautomerase and dopachrome tautomerase activity (in vitro), but the physiological substrate is not known. It is not clear whether the tautomerase activity has any physiological relevance, and whether it is important for cytokine activity.
Gene Name:
Uniprot ID:
Molecular weight:
Phenylpyruvic acid → Enol-phenylpyruvatedetails
Phenylpyruvic acid → Enol-phenylpyruvatedetails
General function:
Involved in 1-aminocyclopropane-1-carboxylate synthase activity
Specific function:
Transaminase involved in tyrosine breakdown. Converts tyrosine to p-hydroxyphenylpyruvate. Can catalyze the reverse reaction, using glutamic acid, with 2-oxoglutarate as cosubstrate (in vitro). Has much lower affinity and transaminase activity towards phenylalanine.
Gene Name:
Uniprot ID:
Molecular weight:
L-Phenylalanine + Oxoglutaric acid → Phenylpyruvic acid + L-Glutamic aciddetails
General function:
Involved in transferase activity, transferring nitrogenous groups
Specific function:
Plays a key role in amino acid metabolism (By similarity).
Gene Name:
Uniprot ID:
Molecular weight:
L-Phenylalanine + Oxoglutaric acid → Phenylpyruvic acid + L-Glutamic aciddetails
General function:
Involved in transferase activity, transferring nitrogenous groups
Specific function:
Catalyzes the irreversible transamination of the L-tryptophan metabolite L-kynurenine to form kynurenic acid (KA). Plays a key role in amino acid metabolism. Important for metabolite exchange between mitochondria and cytosol. Facilitates cellular uptake of long-chain free fatty acids.
Gene Name:
Uniprot ID:
Molecular weight:
L-Phenylalanine + Oxoglutaric acid → Phenylpyruvic acid + L-Glutamic aciddetails
General function:
Involved in 1-aminocyclopropane-1-carboxylate synthase activity
Specific function:
Catalyzes the irreversible transamination of the L-tryptophan metabolite L-kynurenine to form kynurenic acid (KA). Metabolizes the cysteine conjugates of certain halogenated alkenes and alkanes to form reactive metabolites. Catalyzes the beta-elimination of S-conjugates and Se-conjugates of L-(seleno)cysteine, resulting in the cleavage of the C-S or C-Se bond.
Gene Name:
Uniprot ID:
Molecular weight:
L-Glutamine + Phenylpyruvic acid → 2-Keto-glutaramic acid + L-Phenylalaninedetails
General function:
Involved in 4-hydroxyphenylpyruvate dioxygenase activity
Specific function:
Key enzyme in the degradation of tyrosine.
Gene Name:
Uniprot ID:
Molecular weight:
Phenylpyruvic acid + Oxygen → Ortho-Hydroxyphenylacetic acid + Carbon dioxidedetails
General function:
Involved in oxidoreductase activity
Specific function:
Lysosomal L-amino-acid oxidase with highest specific activity with phenylalanine. May play a role in lysosomal antigen processing and presentation (By similarity).
Gene Name:
Uniprot ID:
Molecular weight:
L-Phenylalanine + Water + Oxygen → Phenylpyruvic acid + Ammonia + Hydrogen peroxidedetails