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Record Information
StatusExpected but not Quantified
Creation Date2012-09-11 17:45:57 UTC
Update Date2019-07-23 06:09:40 UTC
Secondary Accession Numbers
  • HMDB31849
Metabolite Identification
Common Name2-Ethylpyrazine
Description2-Ethylpyrazine, also known as fema 3281 or moldin, belongs to the class of organic compounds known as pyrazines. Pyrazines are compounds containing a pyrazine ring, which is a six-member aromatic heterocycle, that consists of two nitrogen atoms (at positions 1 and 4) and four carbon atoms. 2-Ethylpyrazine is a moderately basic compound (based on its pKa). 2-Ethylpyrazine is a bitter, cocoa, and musty tasting compound. Outside of the human body, 2-Ethylpyrazine has been detected, but not quantified in, several different foods, such as asparagus, pulses, cocoa and cocoa products, cereals and cereal products, and tortilla chips. This could make 2-ethylpyrazine a potential biomarker for the consumption of these foods.
FEMA no. 3281ChEBI
Chemical FormulaC6H8N2
Average Molecular Weight108.1411
Monoisotopic Molecular Weight108.068748266
IUPAC Name2-ethylpyrazine
Traditional Name2-ethyl pyrazine
CAS Registry Number13925-00-3
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as pyrazines. Pyrazines are compounds containing a pyrazine ring, which is a six-member aromatic heterocycle, that consists of two nitrogen atoms (at positions 1 and 4) and four carbon atoms.
KingdomOrganic compounds
Super ClassOrganoheterocyclic compounds
Sub ClassPyrazines
Direct ParentPyrazines
Alternative Parents
  • Pyrazine
  • Heteroaromatic compound
  • Azacycle
  • Organic nitrogen compound
  • Organopnictogen compound
  • Hydrocarbon derivative
  • Organonitrogen compound
  • Aromatic heteromonocyclic compound
Molecular FrameworkAromatic heteromonocyclic compounds
External Descriptors

Route of exposure:


Biological location:


Industrial application:

Physical Properties
StateNot Available
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogP0.69Not Available
Predicted Properties
Water Solubility206 g/LALOGPS
pKa (Strongest Basic)1.27ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count2ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area25.78 ŲChemAxon
Rotatable Bond Count1ChemAxon
Refractivity30.96 m³·mol⁻¹ChemAxon
Polarizability11.66 ųChemAxon
Number of Rings1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterNoChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleNoChemAxon
Spectrum TypeDescriptionSplash KeyView
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-0a4i-9700000000-f6a542b90b45a0c8ac2dSpectrum
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-0a4i-9700000000-f6a542b90b45a0c8ac2dSpectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0apl-9200000000-25b4ee3d8e2ba3fc07ccSpectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 2V, positivesplash10-0a4i-0900000000-73c19aad05b8b627b079Spectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 2V, positivesplash10-0a4i-0900000000-9dbcc965c21302f00ad8Spectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 3V, positivesplash10-0a4i-3900000000-ff310f3a4ddde4509fafSpectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 4V, positivesplash10-0a4l-9700000000-73ee1cfd06dee0f717a7Spectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 4V, positivesplash10-0006-9200000000-8af6806d15845b24ac0cSpectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 6V, positivesplash10-0006-9000000000-22d67cc4f9c8b5956971Spectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 7V, positivesplash10-0006-9000000000-e60227e8966ba4acab5bSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0a4i-0900000000-3524228f918635f67c86Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0a4i-2900000000-21aac0dee54f62a0c194Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0udl-9000000000-272487c72d5e01923b92Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0a4i-0900000000-c5a08a210c001d84b6faSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0a4i-1900000000-d64b8d4f12c29a9cfab6Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0zi0-9100000000-3323ef05a3b140f4267dSpectrum
MSMass Spectrum (Electron Ionization)splash10-0a4i-8900000000-2b2fb4b75d5a265c3701Spectrum
1D NMR1H NMR SpectrumNot AvailableSpectrum
1D NMR13C NMR SpectrumNot AvailableSpectrum
Biological Properties
Cellular Locations
  • Cytoplasm
  • Extracellular
Biospecimen LocationsNot Available
Tissue LocationsNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FooDB IDFDB008533
KNApSAcK IDNot Available
Chemspider ID24533
KEGG Compound IDNot Available
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkNot Available
METLIN IDNot Available
PubChem Compound26331
PDB IDNot Available
ChEBI ID73232
Food Biomarker OntologyNot Available
VMH IDNot Available
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General References
  1. Rappert S, Li R, Kokova M, Antholz M, Nagorny S, Francke W, Muller R: Degradation of 2,5-dimethylpyrazine by Rhodococcus erythropolis strain DP-45 isolated from a waste gas treatment plant of a fishmeal processing company. Biodegradation. 2007 Oct;18(5):585-96. Epub 2006 Nov 22. [PubMed:17120096 ]
  2. Melkonian G, Eckelhoefer H, Wu M, Wang Y, Tong C, Riveles K, Talbot P: Growth and angiogenesis are inhibited in vivo in developing tissues by pyrazine and its derivatives. Toxicol Sci. 2003 Oct;75(2):393-401. Epub 2003 May 28. [PubMed:12773771 ]
  3. Fan W, Qian MC: Characterization of aroma compounds of chinese "Wuliangye" and "Jiannanchun" liquors by aroma extract dilution analysis. J Agric Food Chem. 2006 Apr 5;54(7):2695-704. [PubMed:16569063 ]
  4. Shu CK: Pyrazine formation from serine and threonine. J Agric Food Chem. 1999 Oct;47(10):4332-5. [PubMed:10552811 ]
  5. Jung MY, Bock JY, Baik SO, Lee JH, Lee TK: Effects of roasting on pyrazine contents and oxidative stability of red pepper seed oil prior to its extraction. J Agric Food Chem. 1999 Apr;47(4):1700-4. [PubMed:10564041 ]
  6. Jess I, Nather C: Investigations on the synthesis, structures, and properties of new copper(I) 2,3-dimethylpyrazine coordination compounds. Inorg Chem. 2006 Sep 4;45(18):7446-54. [PubMed:16933949 ]
  7. Counet C, Callemien D, Ouwerx C, Collin S: Use of gas chromatography-olfactometry to identify key odorant compounds in dark chocolate. Comparison of samples before and after conching. J Agric Food Chem. 2002 Apr 10;50(8):2385-91. [PubMed:11929301 ]
  8. Montague SA, Mathew D, Carlson JR: Similar odorants elicit different behavioral and physiological responses, some supersustained. J Neurosci. 2011 May 25;31(21):7891-9. doi: 10.1523/JNEUROSCI.6254-10.2011. [PubMed:21613503 ]
  9. Piccone P, Lonzarich V, Navarini L, Fusella G, Pittia P: Effect of sugars on liquid-vapour partition of volatile compounds in ready-to-drink coffee beverages. J Mass Spectrom. 2012 Sep;47(9):1120-31. doi: 10.1002/jms.3073. [PubMed:22972780 ]
  10. Qian M, Reineccius G: Identification of aroma compounds in Parmigiano-Reggiano cheese by gas chromatography/olfactometry. J Dairy Sci. 2002 Jun;85(6):1362-9. [PubMed:12146465 ]
  11. Le Guen S, Prost C, Demaimay M: Critical comparison of three olfactometric methods for the identification of the most potent odorants in cooked mussels (Mytilus edulis). J Agric Food Chem. 2000 Apr;48(4):1307-14. [PubMed:10775390 ]
  12. Morais VM, Miranda MS, Matos MA: Thermochemical study of the ethylpyridine and ethylpyrazine isomers. Org Biomol Chem. 2003 Dec 7;1(23):4329-34. Epub 2003 Oct 27. [PubMed:14685337 ]
  13. (). Yannai, Shmuel. (2004) Dictionary of food compounds with CD-ROM: Additives, flavors, and ingredients. Boca Raton: Chapman & Hall/CRC.. .