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Record Information
StatusExpected but not Quantified
Creation Date2019-06-27 17:24:11 UTC
Update Date2019-10-24 17:45:44 UTC
Secondary Accession NumbersNone
Metabolite Identification
Common NameRactopamine
DescriptionRactopamine (CAS: 97825-25-7) is a beta-agonist livestock feed additive used to increase lean muscle mass. Pharmacologically, ractopamine is a TAAR1 agonist and beta adrenoreceptor agonist that stimulates beta1 and beta2 adrenergic receptors (PMID: 24799633 ). In clinical use, beta-agonists relax the smooth muscles of airways, thereby resulting in bronchodilation (i.e. widened airways) and easier breathing. In livestock feed, these compounds are able to alter the ratio in which dietary energy intake is distributed between lean and fat tissue. Increasing protein synthesis results in increased muscle fibre size. Ractopamine is banned in over 160 countries including the member nations of the European Union, China, and Russia. Countries such as the United States and South Korea still permit ractopamine use (PMID: 26761809 ). Serious side effects, including mortality, have been attributed to beta-agonists (e.g. ractopamine and zilpaterol) in cattle and swine. Cooking is not able to completely degrade ractopamine, therefore human exposure to ractopamine is expected in countries where the feed additive is permitted. In humans, beta-agonists containing phenolic hydroxyl groups, are metabolized in the liver and intestine through glucuronidation and sulfation by UDP-glucuronosyltransferase (UGT) 1A6 and 1A9 and sulfotransferase (SULT1A3). Ractopamine is eliminated in urine mostly as its monoglucuronide and monosulfate conjugates (PMID: 27641640 ). Butopamine, the R,R diastereoisomer, is the most active of ractopamine's four diastereoisomers and is responsible for most of the leanness-enhancing effects.
(R)-p-Hydroxy-alpha-((((R)-3-(p-hydroxyphenyl)-1-methylpropyl)amino)methyl)benzyl alcoholChEBI
LY 131126ChEBI
(R)-p-Hydroxy-a-((((R)-3-(p-hydroxyphenyl)-1-methylpropyl)amino)methyl)benzyl alcoholGenerator
(R)-p-Hydroxy-α-((((R)-3-(p-hydroxyphenyl)-1-methylpropyl)amino)methyl)benzyl alcoholGenerator
p-Hydroxy-alpha-(((-3-(p-hydroxyphenyl)-1-methylpropyl)amino)methyl)benzyl alcoholHMDB
Chemical FormulaC18H23NO3
Average Molecular Weight301.386
Monoisotopic Molecular Weight301.167793605
IUPAC Name4-[(1R)-1-hydroxy-2-{[(2R)-4-(4-hydroxyphenyl)butan-2-yl]amino}ethyl]phenol
Traditional Name4-[(1R)-1-hydroxy-2-{[(2R)-4-(4-hydroxyphenyl)butan-2-yl]amino}ethyl]phenol
CAS Registry Number66734-12-1
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as 1-hydroxy-2-unsubstituted benzenoids. These are phenols that are unsubstituted at the 2-position.
KingdomOrganic compounds
Super ClassBenzenoids
Sub Class1-hydroxy-2-unsubstituted benzenoids
Direct Parent1-hydroxy-2-unsubstituted benzenoids
Alternative Parents
  • 1-hydroxy-2-unsubstituted benzenoid
  • Aralkylamine
  • Monocyclic benzene moiety
  • 1,2-aminoalcohol
  • Secondary alcohol
  • Secondary amine
  • Secondary aliphatic amine
  • Organic oxygen compound
  • Aromatic alcohol
  • Alcohol
  • Organooxygen compound
  • Organonitrogen compound
  • Organic nitrogen compound
  • Amine
  • Hydrocarbon derivative
  • Organopnictogen compound
  • Aromatic homomonocyclic compound
Molecular FrameworkAromatic homomonocyclic compounds
External Descriptors
  • 4-(1-hydroxy-2-\{[4-(4-hydroxyphenyl)butan-2-yl]amino\}ethyl)phenol (CHEBI:82648 )

Industrial application:

Physical Properties
StateNot Available
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
pKa (Strongest Acidic)9.19ChemAxon
pKa (Strongest Basic)9.89ChemAxon
Physiological Charge1ChemAxon
Hydrogen Acceptor Count4ChemAxon
Hydrogen Donor Count4ChemAxon
Polar Surface Area72.72 ŲChemAxon
Rotatable Bond Count7ChemAxon
Refractivity87.62 m³·mol⁻¹ChemAxon
Polarizability34.41 ųChemAxon
Number of Rings2ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Not Available
Biological Properties
Cellular LocationsNot Available
Biospecimen Locations
  • Urine
Tissue LocationsNot Available
Normal Concentrations
UrineExpected but not Quantified Not SpecifiedNot Available
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FoodDB IDNot Available
KNApSAcK IDNot Available
Chemspider ID61830
KEGG Compound IDNot Available
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkRactopamine
METLIN IDNot Available
PubChem Compound68556
PDB IDNot Available
ChEBI ID82648
Food Biomarker OntologyNot Available
VMH IDNot Available
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General References
  1. Liu X, Grandy DK, Janowsky A: Ractopamine, a livestock feed additive, is a full agonist at trace amine-associated receptor 1. J Pharmacol Exp Ther. 2014 Jul;350(1):124-9. doi: 10.1124/jpet.114.213116. Epub 2014 May 5. [PubMed:24799633 ]
  2. Sung IK, Park SJ, Kang K, Kim MY, Cho S: Development and Application of a Method for Rapid and Simultaneous Determination of Three beta-agonists (Clenbuterol, Ractopamine, and Zilpaterol) using Liquid Chromatography-tandem Mass Spectrometry. Korean J Food Sci Anim Resour. 2015;35(1):121-9. doi: 10.5851/kosfa.2015.35.1.121. Epub 2015 Feb 28. [PubMed:26761809 ]
  3. Cheng TD, Shelver WL, Hong CC, McCann SE, Davis W, Zhang Y, Ambrosone CB, Smith DJ: Urinary Excretion of the beta-Adrenergic Feed Additives Ractopamine and Zilpaterol in Breast and Lung Cancer Patients. J Agric Food Chem. 2016 Oct 12;64(40):7632-7639. doi: 10.1021/acs.jafc.6b02723. Epub 2016 Sep 27. [PubMed:27641640 ]