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Record Information
StatusExpected but not Quantified
Creation Date2013-03-04 20:24:46 UTC
Update Date2019-07-23 07:12:55 UTC
Secondary Accession Numbers
  • HMDB59792
Metabolite Identification
Common NameOpiorphin
DescriptionOpiorphin is an endogenous 5-residue opioid peptide (Gln-Arg-Phe-Ser-Arg) first isolated from human saliva. Initial research with mice shows the compound has a painkilling effect greater than that of morphine. It works by stopping the normal breakdown of enkephalins, natural pain-killing opioids in the spinal cord. Opiorphin originates from the N-terminal region of the protein PROL1 (proline rich, lacrimal 1) and inhibits three proteases: neutral ecto-endopeptidase (MME), ecto-aminopeptidase N (ANPEP) and a dipeptidyl peptidase DPP3. This protease inhibitory action extends the duration of enkephalins, which are natural pain killers that are released in response to specific potentially painful stimuli.
Chemical FormulaC29H48N12O8
Average Molecular Weight692.767
Monoisotopic Molecular Weight692.371806572
IUPAC Name(2S)-2-{[(2S)-2-{[(2S)-2-{[(2S)-2-{[(2S)-2-amino-1-hydroxy-4-(C-hydroxycarbonimidoyl)butylidene]amino}-5-carbamimidamido-1-hydroxypentylidene]amino}-1-hydroxy-3-phenylpropylidene]amino}-1,3-dihydroxypropylidene]amino}-5-carbamimidamidopentanoic acid
Traditional Name(2S)-2-{[(2S)-2-{[(2S)-2-{[(2S)-2-{[(2S)-2-amino-1-hydroxy-4-(C-hydroxycarbonimidoyl)butylidene]amino}-5-carbamimidamido-1-hydroxypentylidene]amino}-1-hydroxy-3-phenylpropylidene]amino}-1,3-dihydroxypropylidene]amino}-5-carbamimidamidopentanoic acid
CAS Registry NumberNot Available
InChI Identifier
Chemical Taxonomy
DescriptionThis compound belongs to the class of organic compounds known as oligopeptides. These are organic compounds containing a sequence of between three and ten alpha-amino acids joined by peptide bonds.
KingdomOrganic compounds
Super ClassOrganic acids and derivatives
ClassCarboxylic acids and derivatives
Sub ClassAmino acids, peptides, and analogues
Direct ParentOligopeptides
Alternative Parents
  • Alpha-oligopeptide
  • Phenylalanine or derivatives
  • Glutamine or derivatives
  • N-acyl-l-alpha-amino acid
  • N-acyl-alpha-amino acid
  • N-acyl-alpha amino acid or derivatives
  • Alpha-amino acid amide
  • Serine or derivatives
  • N-substituted-alpha-amino acid
  • Alpha-amino acid or derivatives
  • Amphetamine or derivatives
  • Monocyclic benzene moiety
  • Fatty amide
  • Fatty acyl
  • N-acyl-amine
  • Benzenoid
  • Amino acid or derivatives
  • Amino acid
  • Carboxamide group
  • Guanidine
  • Primary carboxylic acid amide
  • Secondary carboxylic acid amide
  • Carboximidamide
  • Propargyl-type 1,3-dipolar organic compound
  • Organic 1,3-dipolar compound
  • Monocarboxylic acid or derivatives
  • Carboxylic acid
  • Alcohol
  • Organopnictogen compound
  • Hydrocarbon derivative
  • Primary aliphatic amine
  • Organic oxygen compound
  • Carbonyl group
  • Organic nitrogen compound
  • Organic oxide
  • Organonitrogen compound
  • Organooxygen compound
  • Primary alcohol
  • Primary amine
  • Amine
  • Aromatic homomonocyclic compound
Molecular FrameworkAromatic homomonocyclic compounds
External DescriptorsNot Available
Not Available
Physical Properties
StateNot Available
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility0.12 g/LALOGPS
pKa (Strongest Acidic)3.31ChemAxon
pKa (Strongest Basic)12.3ChemAxon
Physiological Charge3ChemAxon
Hydrogen Acceptor Count20ChemAxon
Hydrogen Donor Count15ChemAxon
Polar Surface Area381.79 ŲChemAxon
Rotatable Bond Count23ChemAxon
Refractivity208.34 m³·mol⁻¹ChemAxon
Polarizability71.52 ųChemAxon
Number of Rings1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash KeyView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0f6x-9240535000-837e548c02bd3266bd2bJSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0729-1520219000-ae63d44cc1d9e984abb4JSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0nt9-4950212000-2fae7176985aec3dbfadJSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-114i-6920000000-3de2c9545a91010bb1a8JSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-05u7-0000009000-8803c4f7c24df02272f6JSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0a59-3100009000-1970d4b1ed57fb79997bJSpectraViewer | MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-052f-9310101000-661b0929abbcf656ed4cJSpectraViewer | MoNA
Biological Properties
Cellular LocationsNot Available
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
FoodDB IDNot Available
KNApSAcK IDNot Available
Chemspider IDNot Available
KEGG Compound IDNot Available
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkNot Available
METLIN IDNot Available
PubChem Compound25195667
PDB IDNot Available
ChEBI IDNot Available
Food Biomarker OntologyNot Available
VMH IDNot Available
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General ReferencesNot Available