From Wikipedia, the free encyclopedia
Cyclorphan structure.svg
  • (−)-3-Hydroxy-N-cyclopropylmethylmorphinan
CAS Number
PubChem CID
CompTox Dashboard (EPA)
ECHA InfoCard100.021.825 Edit this at Wikidata
Chemical and physical data
Molar mass297.442 g·mol−1
3D model (JSmol)
Density1.19 g/cm3
Melting point188 °C (370 °F)
Boiling point458.4 °C (857.1 °F)
  • Oc1ccc4c(c1)[C@@]25[C@H]([C@H](N(CC2)CC3CC3)C4)CCCC5

Cyclorphan is an opioid analgesic of the morphinan family that was never marketed.[1] It acts as a μ-opioid receptor (MOR) weak partial agonist or antagonist, κ-opioid receptor (KOR) full agonist, and, to a much lesser extent, δ-opioid receptor (DOR) agonist (75-fold lower affinity relative to the KOR).[2][3] The drug was first synthesized in 1964 by scientists at Research Corporation.[4][5]: 232  In clinical trials, it had relatively long duration, good absorption, and provided strong pain relief but produced psychotomimetic effects via KOR activation, so its development was not continued.[1][5]: 232, 237 

See also[edit]


  1. ^ a b Maxwell Gordon (2 December 2012). Psychopharmacological Agents. Elsevier Science. pp. 19–. ISBN 978-0-323-15963-0.
  2. ^ Linda P. Dwoskin (29 January 2014). Emerging Targets & Therapeutics in the Treatment of Psychostimulant Abuse. Elsevier Science. pp. 403–. ISBN 978-0-12-420177-4.
  3. ^ Aldrich JV, Vigil-Cruz SC (2003). "Narcotic Analgesics". Burger's Medicinal Chemistry and Drug Discovery (7th ed.). pp. 331–482. doi:10.1002/0471266949.bmc100. ISBN 9780471266945.
  4. ^ US Patent 3,285,922
  5. ^ a b 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. ISBN 9783527676552