Cyclorphan is an

opioid Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioid use ...

analgesic of the

morphinan Morphinan is the prototype chemical structure of a large chemical class of psychoactive drugs, consisting of opiate analgesics, cough suppressants, and dissociative hallucinogens, among others. Structure Morphinan has a phenanthrene core struct ...

family that was never marketed. It acts as a

μ-opioid receptor The μ-opioid receptors (MOR) are a class of opioid receptors with a high affinity for enkephalins and beta-endorphin, but a low affinity for dynorphins. They are also referred to as μ(''mu'')-opioid peptide (MOP) receptors. The prototypical � ...

(MOR) weak

partial agonist In pharmacology, partial agonists are drugs that bind to and activate a given receptor, but have only partial efficacy at the receptor relative to a full agonist. They may also be considered ligands which display both agonistic and antagonis ...

or antagonist,

κ-opioid receptor The κ-opioid receptor or kappa opioid receptor, abbreviated KOR or KOP, is a G protein-coupled receptor that in humans is encoded by the ''OPRK1'' gene. The KOR is coupled to the G protein Gi/G0 and is one of four related receptors that bind op ...

(KOR)

full agonist An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the a ...

, and, to a much lesser extent,

δ-opioid receptor The δ-opioid receptor, also known as delta opioid receptor or simply delta receptor, abbreviated DOR or DOP, is an inhibitory 7-transmembrane G-protein coupled receptor coupled to the G protein Gi/G0 and has enkephalins as its endogenous lig ...

(DOR) agonist (75-fold lower

affinity Affinity may refer to: Commerce, finance and law * Affinity (law), kinship by marriage * Affinity analysis, a market research and business management technique * Affinity Credit Union, a Saskatchewan-based credit union * Affinity Equity Par ...

relative to the KOR). The drug was first synthesized in 1964 by scientists at

Research Corporation Research Corporation for Science Advancement (RCSA) is an organization in the United States devoted to the advancement of science, funding research projects in the physical sciences. Since 1912, Research Corporation for Science Advancement has id ...

.US Patent 3,285,922
/ref>Varghese V & Hudlicky T. A Short History of the Discovery and Development of Naltrexone and Other Morphine Derivatives. Chapter 6 in Natural Products in Medicinal Chemistry, Volume 60 of Methods and Principles in Medicinal Chemistry. Ed. Stephen Hanessian. John Wiley & Sons, 2013. In

clinical trial Clinical trials are prospective biomedical or behavioral research studies on human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel vaccines, drugs, diet ...

s, it had relatively long duration, good absorption, and provided strong pain relief but produced

psychotomimetic A drug with psychotomimetic (also known as psychotogenic) actions mimics the symptoms of psychosis, including delusions and/or delirium, as opposed to only hallucinations. Psychotomimesis is the onset of psychotic symptoms following the administrati ...

effects via KOR activation, so its development was not continued.

References

Synthetic opioids Kappa-opioid receptor agonists Delta-opioid receptor agonists Dissociative drugs Morphinans Phenols Cyclopropanes {{analgesic-stub

See also

References