A compound that exhibits agonist activity at the mu-opioid receptor.
| Member | Definition | Class |
|---|
| 3-methylfentanyl | The monocarboxylic acid amide resulting from the formal condensation of the aryl amino group of 3-methyl-N-phenyl-1-(2-phenylethyl)piperidin-4-amine with propanoic acid. | 3-methylfentanyl |
| alfentanil | A member of the class of piperidines that is piperidine having a 2-(4-ethyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)ethyl group at the 1-position as well as N-phenylpropanamido- and methoxymethyl groups at the 4-position. | alfentanil |
| buprenorphine | A morphinane alkaloid that is 7,8-dihydromorphine 6-O-methyl ether in which positions 6 and 14 are joined by a -CH2CH2- bridge, one of the hydrogens of the N-methyl group is substituted by cyclopropyl, and a hydrogen at position 7 is substituted by a 2-hydroxy-3,3-dimethylbutan-2-yl group. It is highly effective for the treatment of opioid use disorder and is also increasingly being used in the treatment of chronic pain. | buprenorphine |
| butorphanol | Levorphanol in which a hydrogen at position 14 of the morphinan skeleton is substituted by hydroxy and one of the hydrogens of the N-methyl group is substituted by cyclopropyl. A semi-synthetic opioid agonist-antagonist analgesic, it is used as its (S,S)-tartaric acid salt for relief or moderate to severe pain. | butorphanol |
| carfentanil | A monocarboxylic acid amide resulting from the formal condensation of the aryl amino group of methyl 4-anilino-1-(2-phenylethyl)piperidine-4-carboxylate with propanoic acid. | carfentanil |
| dextropropoxyphene | The (1S,2R)-(+)-diastereoisomer of propoxyphene. | dextropropoxyphene |
| eluxadoline | An amino acid amide obtained by the formal condensation of the carboxy group of 4-carbamoyl-2,6-dimethyl-L-phenylalanine with the secondary amino group of 2-methoxy-5-({[(1S)-1-(4-phenylimidazol-2-yl)ethyl]amino}methyl)benzoic acid. It has mixed opioid receptor activity and is used for treatment of irritable bowel syndrome with diarrhoea. | eluxadoline |
| enkephalin, leucine | A pentapeptide comprising L-tyrosine, glycine, glycine, L-phenylalanine and L-leucine residues joined in sequence by peptide linkages. It is an endogenous opioid peptide produced in vertebrate species, including rodents, primates and humans that results from decomposition of proenkephalin or dynorphin and exhibits antinociceptive properties. | Leu-enkephalin zwitterion; Leu-enkephalin |
| enkephalin, methionine | A pentapeptide comprising L-tyrosine, glycine, glycine, L-phenylalanine and L-methionine residues joined in sequence by peptide linkages. It is an endogenous opioid peptide with antitumor, analgesic, and immune-boosting properties. | Met-enkephalin zwitterion; Met-enkephalin |
| fentanyl | A monocarboxylic acid amide resulting from the formal condensation of the aryl amino group of N-phenyl-1-(2-phenylethyl)piperidin-4-amine with propanoic acid. | fentanyl |
| fentanyl citrate | The citric acid salt of fentanyl, comprising equimolar amounts of citric acid and fentanyl. A mu-opioid receptor agonist, it is a potent opioid analgesic used in the management of labour pain, postoperative pain, and chronic intractable cancer pain. It is also widely used as the analgesic component of balanced anaesthesia. | fentanyl citrate |
| heroin | A morphinane alkaloid that is morphine bearing two acetyl substituents on the O-3 and O-6 positions. As with other opioids, heroin is used as both an analgesic and a recreational drug. Frequent and regular administration is associated with tolerance and physical dependence, which may develop into addiction. Its use includes treatment for acute pain, such as in severe physical trauma, myocardial infarction, post-surgical pain, and chronic pain, including end-stage cancer and other terminal illnesses. | heroin |
| hydrocodone | A morphinane-like compound that is a semi-synthetic opioid synthesized from codeine. | hydrocodone |
| hydromorphone | A morphinane alkaloid that is a hydrogenated ketone derivative of morphine. A semi-synthetic drug, it is a centrally acting pain medication of the opioid class. | hydromorphone |
| levomethadone | A 6-(dimethylamino)-4,4-diphenylheptan-3-one that has (R)-configuration. It is the active enantiomer of methadone and its hydrochloride salt is used to treat adults who are addicted to drugs such as heroin and morphine. | levomethadone |
| lofentanil | The carboxamide resulting from the formal condensation of the aryl amino group of methyl 4-anilino-3-methyl-1-(2-phenylethyl)piperidine-4-carboxylate with propanoic acid. | lofentanyl |
| loperamide | A synthetic piperidine derivative, effective against diarrhoea resulting from gastroenteritis or inflammatory bowel disease. | loperamide |
| loperamide hydrochloride | A hydrochloride obtained by combining loperamide with one equivalent of hydrochloric acid. Used for treatment of diarrhoea resulting from gastroenteritis or inflammatory bowel disease. | loperamide hydrochloride |
| meperidine | A piperidinecarboxylate ester that is piperidine which is substituted by a methyl group at position 1 and by phenyl and ethoxycarbonyl groups at position 4. It is an analgesic which is used for the treatment of moderate to severe pain, including postoperative pain and labour pain. | pethidine |
| meperidine hydrochloride | The hydrochloride salt of pethidine. An analgesic used for the treatment of postoperative and labour pain. | pethidine hydrochloride |
| morphine | A morphinane alkaloid that is a highly potent opiate analgesic psychoactive drug. Morphine acts directly on the central nervous system (CNS) to relieve pain but has a high potential for addiction, with tolerance and both physical and psychological dependence developing rapidly. Morphine is the most abundant opiate found in Papaver somniferum (the opium poppy). | morphine |
| oxycodone | A semisynthetic opioid of formula C18H21NO4 that is derived from thebaine. It is a moderately potent opioid analgesic, generally used for relief of moderate to severe pain. | oxycodone |
| pholcodine | A morphinane alkaloid that is a derivative of morphine with a 2-morpholinoethyl group at the 3-position. | pholcodine |
| remifentanil | A piperidinecarboxylate ester that is methyl piperidine-4-carboxylate in which the hydrogen attached to the nitrogen is substituted by a 3-methoxy-3-oxopropyl group and the hydrogen at position 4 is substituted the nitrogen of N-propanoylaniline. | remifentanil |
| sufentanil | An anilide resulting from the formal condensation of the aryl amino group of 4-(methoxymethyl)-N-phenyl-1-[2-(2-thienyl)ethyl]piperidin-4-amine with propanoic acid. | sufentanil |
| tramadol | A 2-[(dimethylamino)methyl]-1-(3-methoxyphenyl)cyclohexanol in which both stereocentres have R-configuration; the (R,R)-enantiomer of the racemic opioid analgesic tramadol, it exhibits ten-fold higher analgesic potency than the (S,S)-enantiomer. | (R,R)-tramadol |
| tramadol hydrochloride | A hydrochloride resulting from the reaction of (R,R)-tramadol with 1 molar equivalent of hydrogen chloride; the (R,R)-enantiomer of the racemic opioid analgesic tramadol hydrochloride, it exhibits ten-fold higher analgesic potency than the (S,S)-enantiomer. | (R,R)-tramadol hydrochloride |
| Protein | Taxonomy | Measurement | Average (mM) | Bioassay(s) | Drugs |
|---|
| 15-lipoxygenase, partial | Homo sapiens (human) | Potency | 15.8489 | 1 | 1 |
| AR protein | Homo sapiens (human) | Potency | 23.4627 | 10 | 11 |
| arylsulfatase A | Homo sapiens (human) | Potency | 0.9528 | 1 | 1 |
| ATAD5 protein, partial | Homo sapiens (human) | Potency | 3.2629 | 1 | 1 |
| Ataxin-2 | Homo sapiens (human) | Potency | 19.3931 | 2 | 2 |
| ATP-dependent phosphofructokinase | Trypanosoma brucei brucei TREU927 | Potency | 4.7755 | 1 | 1 |
| ATPase family AAA domain-containing protein 5 | Homo sapiens (human) | Potency | 18.8336 | 1 | 1 |
| atrial natriuretic peptide receptor 2 precursor | Homo sapiens (human) | Potency | 23.2809 | 1 | 1 |
| Bloom syndrome protein isoform 1 | Homo sapiens (human) | Potency | 0.0013 | 2 | 2 |
| caspase 7, apoptosis-related cysteine protease | Homo sapiens (human) | Potency | 33.4915 | 1 | 1 |
| caspase-3 | Homo sapiens (human) | Potency | 33.4915 | 1 | 1 |
| Cellular tumor antigen p53 | Homo sapiens (human) | Potency | 16.6428 | 1 | 2 |
| cellular tumor antigen p53 isoform a | Homo sapiens (human) | Potency | 25.7877 | 1 | 2 |
| Chain A, Ferritin light chain | Equus caballus (horse) | Potency | 19.9526 | 1 | 1 |
| cytochrome P450 2C9, partial | Homo sapiens (human) | Potency | 15.3314 | 1 | 3 |
| cytochrome P450 2D6 | Homo sapiens (human) | Potency | 4.8350 | 1 | 2 |
| cytochrome P450 2D6 isoform 1 | Homo sapiens (human) | Potency | 11.7116 | 1 | 3 |
| cytochrome P450 3A4 isoform 1 | Homo sapiens (human) | Potency | 5.0119 | 2 | 2 |
| cytochrome P450 family 3 subfamily A polypeptide 4 | Homo sapiens (human) | Potency | 5.9353 | 2 | 3 |
| cytochrome P450, family 19, subfamily A, polypeptide 1, isoform CRA_a | Homo sapiens (human) | Potency | 26.6032 | 1 | 1 |
| D(1A) dopamine receptor | Sus scrofa (pig) | Potency | 18.4927 | 1 | 1 |
| Disintegrin and metalloproteinase domain-containing protein 17 | Homo sapiens (human) | Potency | 5.0119 | 1 | 1 |
| endonuclease IV | Escherichia coli | Potency | 7.0795 | 1 | 1 |
| estrogen nuclear receptor alpha | Homo sapiens (human) | Potency | 24.5362 | 8 | 10 |
| estrogen-related nuclear receptor alpha | Homo sapiens (human) | Potency | 21.5213 | 7 | 7 |
| euchromatic histone-lysine N-methyltransferase 2 | Homo sapiens (human) | Potency | 5.5610 | 1 | 2 |
| EWS/FLI fusion protein | Homo sapiens (human) | Potency | 19.2857 | 4 | 4 |
| farnesoid X nuclear receptor | Homo sapiens (human) | Potency | 26.6011 | 1 | 1 |
| G | Vesicular stomatitis virus | Potency | 15.3314 | 1 | 3 |
| GABA theta subunit | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit alpha-1 | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit alpha-2 | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit alpha-3 | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit alpha-4 | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit alpha-5 | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit alpha-6 | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit beta-1 | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit beta-2 | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit beta-3 | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit delta | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit epsilon | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit gamma-1 | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit gamma-2 | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit gamma-3 | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| Gamma-aminobutyric acid receptor subunit pi | Rattus norvegicus (Norway rat) | Potency | 5.0119 | 1 | 1 |
| geminin | Homo sapiens (human) | Potency | 25.0393 | 4 | 7 |
| GLI family zinc finger 3 | Homo sapiens (human) | Potency | 19.2513 | 2 | 2 |
| glp-1 receptor, partial | Homo sapiens (human) | Potency | 5.3882 | 2 | 2 |
| glucocorticoid receptor [Homo sapiens] | Homo sapiens (human) | Potency | 18.7574 | 1 | 2 |
| Glutamate receptor 2 | Rattus norvegicus (Norway rat) | Potency | 29.8493 | 1 | 1 |
| Histamine H2 receptor | Cavia porcellus (domestic guinea pig) | Potency | 16.7658 | 1 | 6 |
| HLA class I histocompatibility antigen, B alpha chain | Homo sapiens (human) | Potency | 15.3314 | 1 | 3 |
| huntingtin isoform 2 | Homo sapiens (human) | Potency | 39.8107 | 1 | 1 |
| IDH1 | Homo sapiens (human) | Potency | 18.3564 | 1 | 1 |
| Inositol hexakisphosphate kinase 1 | Homo sapiens (human) | Potency | 15.3314 | 1 | 6 |
| Inositol monophosphatase 1 | Rattus norvegicus (Norway rat) | Potency | 3.1623 | 1 | 1 |
| Interferon beta | Homo sapiens (human) | Potency | 30.9721 | 2 | 6 |
| lamin isoform A-delta10 | Homo sapiens (human) | Potency | 10.3659 | 1 | 4 |
| Luciferase | Photinus pyralis (common eastern firefly) | Potency | 40.5334 | 1 | 1 |
| M-phase phosphoprotein 8 | Homo sapiens (human) | Potency | 0.8913 | 1 | 1 |
| muscarinic acetylcholine receptor M1 | Rattus norvegicus (Norway rat) | Potency | 17.9008 | 2 | 2 |
| neuropeptide S receptor isoform A | Homo sapiens (human) | Potency | 10.0000 | 1 | 1 |
| nuclear factor erythroid 2-related factor 2 isoform 2 | Homo sapiens (human) | Potency | 29.0929 | 1 | 1 |
| nuclear receptor ROR-gamma isoform 1 | Mus musculus (house mouse) | Potency | 13.1842 | 1 | 2 |
| nuclear receptor subfamily 1, group I, member 3 | Homo sapiens (human) | Potency | 5.8436 | 2 | 2 |
| parathyroid hormone/parathyroid hormone-related peptide receptor precursor | Homo sapiens (human) | Potency | 44.6684 | 1 | 1 |
| peripheral myelin protein 22 | Rattus norvegicus (Norway rat) | Potency | 13.5998 | 1 | 2 |
| peripheral myelin protein 22 isoform 1 | Homo sapiens (human) | Potency | 33.8078 | 1 | 1 |
| peroxisome proliferator activated receptor gamma | Homo sapiens (human) | Potency | 16.7842 | 1 | 1 |
| peroxisome proliferator-activated receptor delta | Homo sapiens (human) | Potency | 18.2368 | 1 | 2 |
| phosphopantetheinyl transferase | Bacillus subtilis | Potency | 112.2020 | 1 | 1 |
| plasminogen precursor | Mus musculus (house mouse) | Potency | 6.3096 | 1 | 1 |
| polyunsaturated fatty acid lipoxygenase ALOX12 | Homo sapiens (human) | Potency | 39.8107 | 1 | 1 |
| Polyunsaturated fatty acid lipoxygenase ALOX15B | Homo sapiens (human) | Potency | 16.7658 | 1 | 3 |
| potassium voltage-gated channel subfamily H member 2 isoform d | Homo sapiens (human) | Potency | 1.0116 | 1 | 3 |
| PPM1D protein | Homo sapiens (human) | Potency | 46.6128 | 1 | 2 |
| pregnane X nuclear receptor | Homo sapiens (human) | Potency | 10.0000 | 1 | 1 |
| RAR-related orphan receptor gamma | Mus musculus (house mouse) | Potency | 5.3080 | 1 | 1 |
| ras-related protein Rab-9A | Homo sapiens (human) | Potency | 58.0479 | 1 | 2 |
| regulator of G-protein signaling 4 | Homo sapiens (human) | Potency | 8.4368 | 1 | 1 |
| retinoic acid nuclear receptor alpha variant 1 | Homo sapiens (human) | Potency | 21.1317 | 1 | 2 |
| retinoid X nuclear receptor alpha | Homo sapiens (human) | Potency | 25.3315 | 1 | 1 |
| serine/threonine-protein kinase mTOR isoform 1 | Homo sapiens (human) | Potency | 17.1425 | 4 | 4 |
| SMAD family member 2 | Homo sapiens (human) | Potency | 10.6822 | 1 | 1 |
| SMAD family member 3 | Homo sapiens (human) | Potency | 10.6822 | 1 | 1 |
| Spike glycoprotein | Severe acute respiratory syndrome-related coronavirus | Potency | 14.1254 | 1 | 1 |
| survival motor neuron protein isoform d | Homo sapiens (human) | Potency | 33.0488 | 1 | 3 |
| TDP1 protein | Homo sapiens (human) | Potency | 15.6142 | 2 | 12 |
| thioredoxin glutathione reductase | Schistosoma mansoni | Potency | 89.1251 | 1 | 1 |
| thioredoxin reductase | Rattus norvegicus (Norway rat) | Potency | 0.7519 | 1 | 1 |
| Thrombopoietin | Homo sapiens (human) | Potency | 12.5893 | 2 | 2 |
| thyroid hormone receptor beta isoform 2 | Rattus norvegicus (Norway rat) | Potency | 7.9552 | 2 | 2 |
| thyroid hormone receptor beta isoform a | Homo sapiens (human) | Potency | 63.0957 | 1 | 1 |
| thyroid stimulating hormone receptor | Homo sapiens (human) | Potency | 14.1095 | 2 | 3 |
| ubiquitin carboxyl-terminal hydrolase 2 isoform a | Homo sapiens (human) | Potency | 5.0119 | 1 | 1 |
| urokinase plasminogen activator surface receptor precursor | Mus musculus (house mouse) | Potency | 6.3096 | 1 | 1 |
| urokinase-type plasminogen activator precursor | Mus musculus (house mouse) | Potency | 6.3096 | 1 | 1 |
| Voltage-dependent calcium channel gamma-2 subunit | Mus musculus (house mouse) | Potency | 29.8493 | 1 | 1 |