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Record Information
Creation Date2006-02-28 17:19:06 UTC
Update Date2016-05-13 22:19:57 UTC
Secondary Accession NumbersNone
Metabolite Identification
Common NameAcetylcysteine
DescriptionAcetylcysteine is the N-acetyl derivative of the amino acid L-cysteine, and is a precursor in the formation of the antioxidant glutathione in the body. The thiol (sulfhydryl) group confers antioxidant effects and is able to reduce free radicals. wikipedia. It is used as a mucolytic agent to reduce the viscosity of mucous secretions. It has also been shown to have antiviral effects in patients with HIV due to inhibition of viral stimulation by reactive oxygen intermediates. -- Pubchem. Acetylcysteine is a pharmacological agent used in the management of paracetamol overdose. For these indications, acetylcysteine is available under the trade names Mucomyst (Bristol-Myers Squibb) and Parvolex (GSK.-- Wikipedia.
(2R)-2-acetylamino-3-Sulfanylpropanoic acidChEBI
(R)-2-acetylamino-3-Mercaptopropanoic acidChEBI
(R)-Mercapturic acidChEBI
L-alpha-acetamido-beta-Mercaptopropionic acidChEBI
Mercapturic acidChEBI
(2R)-2-acetylamino-3-Sulphanylpropanoic acidGenerator
(2R)-2-acetamido-3-Sulphanylpropanoic acidGenerator
(R)-Mercaptic acidGenerator
L-a-acetamido-b-Mercaptopropionic acidGenerator
L-α-acetamido-β-mercaptopropionic acidGenerator
Mercaptic acidGenerator
2-acetylamino-3-mercapto-Propionic acidHMDB
Fluimicil infantilHMDB
Sodium 2-acetamido-3-mercaptopropionateHMDB
Chemical FormulaC5H9NO3S
Average Molecular Weight163.195
Monoisotopic Molecular Weight163.030313849
IUPAC Name(2R)-2-acetamido-3-sulfanylpropanoic acid
Traditional Nameacetylcysteine
CAS Registry Number616-91-1
InChI Identifier
Chemical Taxonomy
DescriptionThis compound belongs to the class of organic compounds known as n-acyl-aliphatic-alpha amino acids. These are alpha amino acids carrying a N-acylated aliphatic chain.
KingdomOrganic compounds
Super ClassOrganic acids and derivatives
ClassCarboxylic acids and derivatives
Sub ClassAmino acids, peptides, and analogues
Direct ParentN-acyl-aliphatic-alpha amino acids
Alternative Parents
  • N-acyl-aliphatic-alpha amino acid
  • N-acyl-l-alpha-amino acid
  • Acetamide
  • Secondary carboxylic acid amide
  • Carboxamide group
  • Monocarboxylic acid or derivatives
  • Carboxylic acid
  • Carboxylic acid amide
  • Alkylthiol
  • Hydrocarbon derivative
  • Organosulfur compound
  • Organooxygen compound
  • Organonitrogen compound
  • Carbonyl group
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External Descriptors
StatusDetected and Quantified
  • Endogenous
  • Anti-oxidant
ApplicationNot Available
Cellular locations
  • Cytoplasm (predicted from logP)
Physical Properties
Experimental Properties
Melting Point109.5 °CNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility5.09 mg/mLALOGPS
pKa (Strongest Acidic)3.82ChemAxon
pKa (Strongest Basic)-1.5ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count3ChemAxon
Polar Surface Area66.4 Å2ChemAxon
Rotatable Bond Count3ChemAxon
Refractivity37.67 m3·mol-1ChemAxon
Polarizability15.34 Å3ChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash Key
GC-MSGC-MS Spectrum - GC-MS (3 TMS)splash10-0i00-2970000000-d817070e3a42f5e63ec5View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-00di-0900000000-b0d92bfcc2536077a6fcView in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-004i-9000000000-f305286cee84e6ae992bView in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-0a4l-9000000000-b10b4a2a6383336db871View in MoNA
1D NMR1H NMR SpectrumNot Available
2D NMR[1H,13C] 2D NMR SpectrumNot Available
Biological Properties
Cellular Locations
  • Cytoplasm (predicted from logP)
Biofluid Locations
  • Blood
  • Urine
Tissue Location
  • Fibroblasts
  • Gut
  • Kidney
  • Liver
  • Myelin
  • Placenta
PathwaysNot Available
Normal Concentrations
BloodDetected and Quantified4.0 (4.29-5.0) uMAdult (>18 years old)BothNormal details
UrineDetected and Quantified0-0.13 umol/mmol creatinineAdult (>18 years old)BothNormal
    • Great Plains Labo...
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDDB06151
DrugBank Metabolite IDNot Available
Phenol Explorer Compound IDNot Available
Phenol Explorer Metabolite IDNot Available
FoodDB IDFDB002281
KNApSAcK IDNot Available
Chemspider ID11540
KEGG Compound IDC06809
BioCyc IDCPD-9175
BiGG IDNot Available
Wikipedia LinkAcetylcysteine
NuGOwiki LinkHMDB01890
Metagene LinkHMDB01890
PubChem Compound12035
ChEBI ID28939
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Faucet-Marquis V, Pont F, Stormer FC, Rizk T, Castegnaro M, Pfohl-Leszkowicz A: Evidence of a new dechlorinated ochratoxin A derivative formed in opossum kidney cell cultures after pretreatment by modulators of glutathione pathways: correlation with DNA-adduct formation. Mol Nutr Food Res. 2006 May;50(6):530-42. [16671059 ]
  2. Wilkes JM, Clark LE, Herrera JL: Acetaminophen overdose in pregnancy. South Med J. 2005 Nov;98(11):1118-22. [16351032 ]
  3. Weigand MA, Plachky J, Thies JC, Spies-Martin D, Otto G, Martin E, Bardenheuer HJ: N-acetylcysteine attenuates the increase in alpha-glutathione S-transferase and circulating ICAM-1 and VCAM-1 after reperfusion in humans undergoing liver transplantation. Transplantation. 2001 Aug 27;72(4):694-8. [11544433 ]
  4. Soheili Majd E, Goldberg M, Stanislawski L: In vitro effects of ascorbate and Trolox on the biocompatibility of dental restorative materials. Biomaterials. 2003 Jan;24(1):3-9. [12417172 ]
  5. Cereser C, Boget S, Parvaz P, Revol A: Thiram-induced cytotoxicity is accompanied by a rapid and drastic oxidation of reduced glutathione with consecutive lipid peroxidation and cell death. Toxicology. 2001 Jun 21;163(2-3):153-62. [11516525 ]
  6. Hein OV, Ohring R, Schilling A, Oellerich M, Armstrong VW, Kox WJ, Spies C: N-acetylcysteine decreases lactate signal intensities in liver tissue and improves liver function in septic shock patients, as shown by magnetic resonance spectroscopy: extended case report. Crit Care. 2004 Apr;8(2):R66-71. Epub 2004 Jan 22. [15025780 ]
  7. Kramers C, Jansman FG, Droogleever Fortuyn H: [A patient who refused treatment after self-poisoning with paracetamol] Ned Tijdschr Geneeskd. 2006 Jul 22;150(29):1601-4. [16901061 ]
  8. Lucena MI, Lopez-Torres E, Verge C, Andrade RJ, Puche MJ, Seoane J, de la Cuesta FS: The administration of N-acetylcysteine causes a decrease in prothrombin time in patients with paracetamol overdose but without evidence of liver impairment. Eur J Gastroenterol Hepatol. 2005 Jan;17(1):59-63. [15647642 ]
  9. Langman M, Boyle P: Chemoprevention of colorectal cancer. Gut. 1998 Oct;43(4):578-85. [9824590 ]
  10. Alscher DM, Braun N, Biegger D, Stuelten C, Gawronski K, Murdter TE, Kuhlmann U, Fritz P: Induction of metallothionein in proximal tubular cells by zinc and its potential as an endogenous antioxidant. Kidney Blood Press Res. 2005;28(3):127-33. Epub 2005 Apr 5. [15812196 ]
  11. Hook GE, Gilmore LB, Talley FA: Dissolution and reassembly of tubular myelin-like multilamellated structures from the lungs of patients with pulmonary alveolar proteinosis. Lab Invest. 1986 Aug;55(2):194-208. [3755483 ]
  12. Dawson AH, Henry DA, McEwen J: Adverse reactions to N-acetylcysteine during treatment for paracetamol poisoning. Med J Aust. 1989 Mar 20;150(6):329-31. [2716644 ]
  13. Bailey B, McGuigan MA: Management of anaphylactoid reactions to intravenous N-acetylcysteine. Ann Emerg Med. 1998 Jun;31(6):710-5. [9624310 ]
  14. Jones AL: Mechanism of action and value of N-acetylcysteine in the treatment of early and late acetaminophen poisoning: a critical review. J Toxicol Clin Toxicol. 1998;36(4):277-85. [9711192 ]
  15. Breitkreutz R, Pittack N, Nebe CT, Schuster D, Brust J, Beichert M, Hack V, Daniel V, Edler L, Droge W: Improvement of immune functions in HIV infection by sulfur supplementation: two randomized trials. J Mol Med (Berl). 2000;78(1):55-62. [10759030 ]
  16. Fulghesu AM, Ciampelli M, Muzj G, Belosi C, Selvaggi L, Ayala GF, Lanzone A: N-acetyl-cysteine treatment improves insulin sensitivity in women with polycystic ovary syndrome. Fertil Steril. 2002 Jun;77(6):1128-35. [12057717 ]
  17. Bachert C, Hormann K, Mosges R, Rasp G, Riechelmann H, Muller R, Luckhaupt H, Stuck BA, Rudack C: An update on the diagnosis and treatment of sinusitis and nasal polyposis. Allergy. 2003 Mar;58(3):176-91. [12653791 ]


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:
General function:
Involved in glycine N-acyltransferase activity
Specific function:
Acyltransferase which transfers an acyl group to the N-terminus of glutamine. Can use phenylacetyl-CoA as an acyl donor.
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in glycine N-acyltransferase activity
Specific function:
Mitochondrial acyltransferase which transfers the acyl group to the N-terminus of glycine. Conjugates numerous substrates, such as arachidonoyl-CoA and saturated medium and long-chain acyl-CoAs ranging from chain-length C8:0-CoA to C18:0-CoA, to form a variety of N-acylglycines. Shows a preference for monounsaturated fatty acid oleoyl-CoA (C18:1-CoA) as an acyl donor. Does not exhibit any activity toward C22:6-CoA and chenodeoxycholoyl-CoA, nor toward serine or alanine.
Gene Name:
Uniprot ID:
Molecular weight:


General function:
Involved in transporter activity
Specific function:
Mediates the Na(+)-independent transport of organic anions such as pravastatin, taurocholate, methotrexate, dehydroepiandrosterone sulfate, 17-beta-glucuronosyl estradiol, estrone sulfate, prostaglandin E2, thromboxane B2, leukotriene C3, leukotriene E4, thyroxine and triiodothyronine. May play an important role in the clearance of bile acids and organic anions from the liver
Gene Name:
Uniprot ID:
Molecular weight:
  1. Daily A, Monks NR, Leggas M, Moscow JA: Abrogation of microcystin cytotoxicity by MAP kinase inhibitors and N-acetyl cysteine is confounded by OATPIB1 uptake activity inhibition. Toxicon. 2010 Apr 1;55(4):827-37. Epub 2009 Nov 24. [19944114 ]