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Record Information
StatusExpected but not Quantified
Creation Date2009-04-06 16:21:20 UTC
Update Date2020-02-26 21:37:09 UTC
Secondary Accession Numbers
  • HMDB12226
Metabolite Identification
Common NameEntacapone
DescriptionEntacapone, also known as comtan or comtess, belongs to the class of organic compounds known as hydroxycinnamic acids and derivatives. Hydroxycinnamic acids and derivatives are compounds containing an cinnamic acid (or a derivative thereof) where the benzene ring is hydroxylated. Entacapone is a drug which is used as an adjunct to levodopa / carbidopa in the symptomatic treatment of patients with idiopathic parkinson's disease who experience the signs and symptoms of end-of-dose "wearing-off". Entacapone is an extremely weak basic (essentially neutral) compound (based on its pKa). Entacapone is a potentially toxic compound. The mechanism of action of entacapone is believed to be through its ability to inhibit COMT in peripheral tissues, altering the plasma pharmacokinetics of levodopa. The function of COMT is the elimination of biologically active catechols and some other hydroxylated metabolites. When entacapone is given in conjunction with levodopa and an aromatic amino acid decarboxylase inhibitor, such as carbidopa, plasma levels of levodopa are greater and more sustained than after administration of levodopa and an aromatic amino acid decarboxylase inhibitor alone. Metabolized via isomerization to the cis-isomer, followed by direct glucuronidation of the parent and cis-isomer. Side effect include increase the occurrence of orthostatic hypotension, severe rhabdomyolysis, dyskinesia, hallucinations, hyperkinesia, hypokinesia, dizziness, fatigu,e gastrointestinal effects including abdominal pain constipation diarrhea nausea.
N,N-Diethyl-2-cyano-3-(3,4-dihydroxy-5-nitrophenyl) acrylamideChEBI
Orion brand OF entacaponeHMDB
Novartis brand OF entacaponeHMDB
Chemical FormulaC14H15N3O5
Average Molecular Weight305.286
Monoisotopic Molecular Weight305.101170605
IUPAC Name(2E)-2-cyano-3-(3,4-dihydroxy-5-nitrophenyl)-N,N-diethylprop-2-enamide
Traditional Nameentacapone
CAS Registry Number130929-57-6
InChI Identifier
Chemical Taxonomy
Description Belongs to the class of organic compounds known as hydroxycinnamic acids and derivatives. Hydroxycinnamic acids and derivatives are compounds containing an cinnamic acid (or a derivative thereof) where the benzene ring is hydroxylated.
KingdomOrganic compounds
Super ClassPhenylpropanoids and polyketides
ClassCinnamic acids and derivatives
Sub ClassHydroxycinnamic acids and derivatives
Direct ParentHydroxycinnamic acids and derivatives
Alternative Parents
  • Hydroxycinnamic acid or derivatives
  • Nitrophenol
  • Nitrobenzene
  • Nitroaromatic compound
  • Catechol
  • 1-hydroxy-4-unsubstituted benzenoid
  • 1-hydroxy-2-unsubstituted benzenoid
  • Phenol
  • Monocyclic benzene moiety
  • Benzenoid
  • Tertiary carboxylic acid amide
  • Carboxamide group
  • C-nitro compound
  • Organic nitro compound
  • Allyl-type 1,3-dipolar organic compound
  • Propargyl-type 1,3-dipolar organic compound
  • Carboxylic acid derivative
  • Carbonitrile
  • Nitrile
  • Organic oxoazanium
  • Organic 1,3-dipolar compound
  • Organic nitrogen compound
  • Organic zwitterion
  • Organic oxide
  • Hydrocarbon derivative
  • Organic oxygen compound
  • Organonitrogen compound
  • Organooxygen compound
  • Carbonyl group
  • Organopnictogen compound
  • Aromatic homomonocyclic compound
Molecular FrameworkAromatic homomonocyclic compounds
External Descriptors
Physiological effect

Health effect:



Route of exposure:


Industrial application:

Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility0.08 g/LALOGPS
pKa (Strongest Acidic)5.68ChemAxon
pKa (Strongest Basic)-0.036ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count6ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area130.38 ŲChemAxon
Rotatable Bond Count5ChemAxon
Refractivity80.51 m³·mol⁻¹ChemAxon
Polarizability29.48 ųChemAxon
Number of Rings1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon


Spectrum TypeDescriptionSplash KeyDeposition DateView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-003r-4190000000-da6b28638ec4920bd58a2017-09-01View Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (2 TMS) - 70eV, Positivesplash10-0059-6004900000-14645ab585cbbed0ca382017-10-06View Spectrum
MSMass Spectrum (Electron Ionization)splash10-003r-4190000000-da6b28638ec4920bd58a2021-09-05View Spectrum


Spectrum TypeDescriptionSplash KeyDeposition DateView
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-qTof , Positivesplash10-0a4i-0329000000-8d20a5650e9c1b1c82752017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - , positivesplash10-0a4i-0329000000-8d20a5650e9c1b1c82752017-09-14View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0a4i-0009000000-6e08b463d5af436175172016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0udr-1069000000-5075a6f93c2b72c3483a2016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0fkc-9240000000-27e088a40b83e29661e02016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0udi-0009000000-29c32f9a04e379fce5fe2016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0udi-2009000000-6d53b89d8a9ecd3b180e2016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-00dl-9100000000-5f330d3ad8cb0af17a9a2016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0a4i-0009000000-62e9f24f62db1840e2e02021-09-08View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-001i-1292000000-28b9a09056bdc465cd192021-09-08View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0a4i-1590000000-58fe447bc05aa84201882021-09-08View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0udi-0039000000-85f49c3b07fd9b1dd7bd2021-09-08View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0pb9-1693000000-bf7093c3dc0b31a75e5d2021-09-08View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0a4j-5910000000-658aee735015de149a672021-09-08View Spectrum
Biological Properties
Cellular LocationsNot Available
Biospecimen LocationsNot Available
Tissue LocationsNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
Predicted Concentrations
BiospecimenValueOriginal ageOriginal sexOriginal conditionComments
Blood0.000 uMAdult (>18 years old)BothNormalPredicted based on drug qualities
Blood0.000 umol/mmol creatinineAdult (>18 years old)BothNormalPredicted based on drug qualities
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDDB00494
Phenol Explorer Compound IDNot Available
FooDB IDFDB028870
KNApSAcK IDNot Available
Chemspider ID4444537
KEGG Compound IDC07943
BioCyc IDCPD-7662
BiGG IDNot Available
Wikipedia LinkEntacapone
METLIN IDNot Available
PubChem Compound5281081
PDB IDNot Available
ChEBI ID4798
Food Biomarker OntologyNot Available
VMH IDNot Available
MarkerDB IDNot Available
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General References
  1. Durif F, Devaux I, Pere JJ, Delumeau JC, Bourdeix I: Efficacy and tolerability of entacapone as adjunctive therapy to levodopa in patients with Parkinson's disease and end-of-dose deterioration in daily medical practice: an open, multicenter study. Eur Neurol. 2001;45(2):111-8. [PubMed:11244274 ]
  2. Factor SA, Molho ES, Feustel PJ, Brown DL, Evans SM: Long-term comparative experience with tolcapone and entacapone in advanced Parkinson's disease. Clin Neuropharmacol. 2001 Sep-Oct;24(5):295-9. [PubMed:11586115 ]
  3. Leppanen J, Savolainen J, Nevalainen T, Forsberg M, Huuskonen J, Taipale H, Gynther J, Mannisto PT, Jarvinen T: Synthesis and in-vitro/in-vivo evaluation of orally administered entacapone prodrugs. J Pharm Pharmacol. 2001 Nov;53(11):1489-98. [PubMed:11732751 ]
  4. Authors unspecified: Entacapone/levodopa/carbidopa combination tablet: Stalevo. Drugs R D. 2003;4(5):310-1. [PubMed:12952501 ]
  5. Authors unspecified: Levodopa + carbidopa + entacapone. Entacapone: a second look: new preparations. Parkinson's disease: a modest effect. Prescrire Int. 2005 Apr;14(76):51-4. [PubMed:15875340 ]
  6. Valkovic P, Benetin J, Blazicek P, Valkovicova L, Gmitterova K, Kukumberg P: Reduced plasma homocysteine levels in levodopa/entacapone treated Parkinson patients. Parkinsonism Relat Disord. 2005 Jun;11(4):253-6. Epub 2005 Apr 20. [PubMed:15878587 ]
  7. Gottwald MD: Entacapone, a catechol-O-methyltransferase inhibitor for treating Parkinson's disease: review and current status. Expert Opin Investig Drugs. 1999 Apr;8(4):453-62. [PubMed:15992091 ]
  8. Kinnings SL, Liu N, Buchmeier N, Tonge PJ, Xie L, Bourne PE: Drug discovery using chemical systems biology: repositioning the safe medicine Comtan to treat multi-drug and extensively drug resistant tuberculosis. PLoS Comput Biol. 2009 Jul;5(7):e1000423. doi: 10.1371/journal.pcbi.1000423. Epub 2009 Jul 3. [PubMed:19578428 ]
  9. Hamaue N, Ogata A, Terado M, Tsuchida S, Yabe I, Sasaki H, Hirafuji M, Togashi H, Aoki T: Entacapone, a catechol-O-methyltransferase inhibitor, improves the motor activity and dopamine content of basal ganglia in a rat model of Parkinson's disease induced by Japanese encephalitis virus. Brain Res. 2010 Jan 14;1309:110-5. doi: 10.1016/j.brainres.2009.10.055. Epub 2009 Oct 29. [PubMed:19879254 ]


General function:
Involved in oxidoreductase activity
Specific function:
Catalyzes the oxidative deamination of biogenic and xenobiotic amines and has important functions in the metabolism of neuroactive and vasoactive amines in the central nervous system and peripheral tissues. MAOB preferentially degrades benzylamine and phenylethylamine.
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in magnesium ion binding
Specific function:
Catalyzes the O-methylation, and thereby the inactivation, of catecholamine neurotransmitters and catechol hormones. Also shortens the biological half-lives of certain neuroactive drugs, like L-DOPA, alpha-methyl DOPA and isoproterenol.
Gene Name:
Uniprot ID:
Molecular weight:
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 has specificity for phenols.
Gene Name:
Uniprot ID:
Molecular weight: