CP 55,940

2-[(1R,2R,5R)-5-hydroxy-2-(3-hydroxypropyl)cyclohexyl]-5-(2-methyloctan-2-yl)phenol

Overview

CP 55,940 belongs to Cannabinoids.

Key safety note: CP 55,940 is a laboratory research compound with limited human safety data and no established safe human dose.[4]
Effects
Subjective effects vary. What a substance feels like depends on dose, individual physiology, mindset, and setting. The points below describe commonly reported effects, not guaranteed, uniform, or desirable outcomes.
  • CP 55,940 is a research compound. Its subjective effects in humans have not been formally characterised in controlled studies. The description below is extrapolated from its pharmacology and from reports of structurally related synthetic cannabinoids, not from systematic human data.
  • As a potent full CB1 agonist it would be expected to produce cannabis-like intoxication: euphoria, relaxation, altered perception of time and space, and impaired coordination, memory and concentration.
  • Severe anxiety, confusion, agitation, cardiovascular disturbances and seizures are concerns based on other synthetic cannabinoid exposures. Their frequency and dose relationship for CP 55,940 in humans are not established.
Dosing & duration
Harm-reduction note: These are commonly cited reference ranges, not a recommendation or a “safe” dose. Potency, purity, body chemistry, tolerance, and drug combinations vary widely. Start low, go slow, wait for full effects before redosing, and never assume an unknown product matches these figures. Missing data is not evidence of safety.

Not reported

Dose ranges

Duration

Chemical & Physical Properties
FormulaC24H40O3
Molar mass376.6 g/mol
StateNot reported
Melting pointNot reported
Boiling pointNot reported
DensityNot reported
Vapor pressureNot reported
pKaNot reported
LogP6.1 (predicted, XLogP3)
SolubilityNot reported
Refractive indexNot reported
Identifiers & Synonyms
CAS83002-04-4
CAS (enantiomer)
PubChem CID104895
InChIKeyYNZFFALZMRAPHQ-SYYKKAFVSA-N
InChIInChI=1S/C24H40O3/c1-4-5-6-7-14-24(2,3)19-11-13-21(23(27)16-19)22-17-20(26)12-10-18(22)9-8-15-25/h11,13,16,18,20,22,25-27H,4-10,12,14-15,17H2,1-3H3/t18-,20-,22-/m1/s1
SMILESCCCCCCC(C)(C)C1=CC(=C(C=C1)[C@@H]2C[C@@H](CC[C@H]2CCCO)O)O

Synonyms

  • CP-55940
  • CP 55,940
  • (−)-CP 55,940
  • 5-(1,1-dimethylheptyl)-2-[5-hydroxy-2-(3-hydroxypropyl)cyclohexyl]phenol
Pharmacodynamics & Biochemistry

CP 55,940 is a synthetic, non-classical cannabinoid of the cyclohexylphenol class, developed by Pfizer in 1974. Unlike the tricyclic 'classical' cannabinoids such as Δ⁹-THC it lacks the fused pyran ring, but it acts on the same targets: behaving as a potent full agonist at both the CB1 and CB2 cannabinoid receptors, with roughly equal affinity for the two (Ki on the order of 1 nM at each). CB1 activation affects mood, perception, memory and motor control, while CB2 activation has peripheral and immune effects. CP 55,940 often shows higher efficacy than THC in experimental systems. Full agonism means reaching the maximum measured response in a particular assay, not producing an unlimited response. Assay potency ratios do not establish relative doses or safety in humans. Its principal importance is historical and pharmacological: the tritiated form, [³H]CP55,940, was the radioligand Devane, Howlett and colleagues used in 1988 to demonstrate and characterise a specific cannabinoid receptor in rat brain (later named CB1): the finding that opened up endocannabinoid pharmacology. It is still a standard reference full agonist in cannabinoid-receptor assays, and it also acts as an antagonist at GPR55, a putative further cannabinoid target.

Biological targets

  • CB1
  • CB2

Binding & functional measurements

TargetMeasurementSpecies
CB1 receptorpKd 8.95Human
CB2 receptorpKd 8.9Human
Pharmacokinetics
BioavailabilityNot reported
TmaxNot reported
Half-lifeNot reported
VdNot reported
Protein bindingNot reported
MetabolismNot reported
ExcretionNot reported
Toxicology & Safety
Harm-reduction note: Toxicity and risk depend on dose, route, purity, combinations, setting, and individual health factors. Missing harms should never be interpreted as evidence of safety.

Not reported

CP 55,940 is a laboratory research compound with limited human safety data and no established safe human dose. Severe intoxication, including agitation, psychosis, seizures and cardiovascular complications, has been reported with other synthetic cannabinoid products. This class-level evidence raises concern but does not quantify CP 55,940-specific human risk. Neither high receptor efficacy nor an in vitro potency ratio defines a safe dose. Unregulated product composition adds uncertainty.[4]

Legal Status
Legal note: Legal status can change over time and may vary by country, region, formulation, analogue status, prescription context, and enforcement practice. Always confirm with current official sources before relying on this section.
Interactions & Contraindications

Drug interactions

Alcohol, Benzodiazepines No human data exist, but by pharmacological class this potent CB1 agonist would add to the sedation and impairment of alcohol, benzodiazepines or other CNS depressants.[4]
Stimulants (amphetamines, cocaine) Its cardiovascular effects (tachycardia, blood-pressure changes) could compound those of stimulants, and its potency is not comparable dose-for-dose with cannabis, making combined use unpredictable.[4]

Contraindications

Usage & Context
  • Primarily a pharmacological research tool used to study the endocannabinoid system. It was synthesised by Pfizer in 1974 as a candidate analgesic but was never marketed.
  • Its tritiated form, [³H]CP55,940, is a classic radioligand for cannabinoid-receptor binding assays and was central to the 1988 identification of the CB1 receptor.
  • Unlike the indole-derived synthetic cannabinoids (e.g. the JWH series) that dominated early 'Spice' products, CP 55,940 itself is rarely encountered as a recreational street drug, though its close analogue CP-47,497 and its C8 homologue (cannabicyclohexanol) were among the first synthetic cannabinoids found in such products.
Sources & Evidence
  1. PubChem: CP 55,940 (CID 104895) — identifiers & computed properties
  2. IUPHAR/BPS Guide to PHARMACOLOGY: [3H]CP55940 (ligand 734) — CB1/CB2 binding data CC BY-SA 4.0
  3. Devane WA, Dysarz FA 3rd, Johnson MR, et al. (1988). Determination and characterization of a cannabinoid receptor in rat brain. Mol Pharmacol 34:605-13.

    PMID 2848184

  4. Wikipedia: CP 55,940 (chemistry, pharmacology, potency & history) CC BY-SA 4.0
  5. DEA Diversion Control Division: Controlled Substances (Alphabetical Order) — CP-55,940 is Schedule I, drug code 7000
  6. GOV.UK: Controlled drugs list — synthetic cannabinoids are Class B under the Misuse of Drugs Act 1971 OGL v3.0
  7. NpSG — Neue-psychoaktive-Stoffe-Gesetz: Stoffgruppen-Definitionen der Cannabimimetika (heteroaromatische Grundstrukturen)
  8. BtMG — Betäubungsmittelgesetz (Gesetze im Internet): CP-47,497 und Homologe seit 2009 in Anlage II
  9. Assay Guidance Manual: Pharmacological Characterization of GPCR Agonists, Antagonists, Allosteric Modulators and Biased Ligands (2019)
  10. Castaneto MS, Gorelick DA, Desrosiers NA, et al. (2014). Synthetic cannabinoids: epidemiology, pharmacodynamics, and clinical implications. Drug Alcohol Depend 144:12-41.

    PMID 25220897 · doi:10.1016/j.drugalcdep.2014.08.005

  11. Felder CC, Veluz JS, Williams HL, et al. (1992). Cannabinoid agonists stimulate both receptor- and non-receptor-mediated signal transduction pathways in cells transfected with and expressing cannabinoid receptor clones. Mol Pharmacol 42:838-45.

    PMID 1331766

  12. Felder CC, Joyce KE, Briley EM, et al. (1995). Comparison of the pharmacology and signal transduction of the human cannabinoid CB1 and CB2 receptors. Mol Pharmacol 48:443-50.

    PMID 7565624

  13. Gérard CM, Mollereau C, Vassart G, et al. (1991). Molecular cloning of a human cannabinoid receptor which is also expressed in testis. Biochem J 279 ( Pt 1):129-34.

    PMID 1718258 · doi:10.1042/bj2790129

  14. Bouaboula M, Bourrié B, Rinaldi-Carmona M, et al. (1995). Stimulation of cannabinoid receptor CB1 induces krox-24 expression in human astrocytoma cells. J Biol Chem 270:13973-80.

    PMID 7775459 · doi:10.1074/jbc.270.23.13973

  15. Bouaboula M, Poinot-Chazel C, Bourrié B, et al. (1995). Activation of mitogen-activated protein kinases by stimulation of the central cannabinoid receptor CB1. Biochem J 312 ( Pt 2):637-41.

    PMID 8526880 · doi:10.1042/bj3120637

  16. Shire D, Calandra B, Delpech M, et al. (1996). Structural features of the central cannabinoid CB1 receptor involved in the binding of the specific CB1 antagonist SR 141716A. J Biol Chem 271:6941-6.

    PMID 8636122 · doi:10.1074/jbc.271.12.6941

  17. Showalter VM, Compton DR, Martin BR, et al. (1996). Evaluation of binding in a transfected cell line expressing a peripheral cannabinoid receptor (CB2): identification of cannabinoid receptor subtype selective ligands. J Pharmacol Exp Ther 278:989-99.

    PMID 8819477

  18. Munro S, Thomas KL, Abu-Shaar M (1993). Molecular characterization of a peripheral receptor for cannabinoids. Nature 365:61-5.

    PMID 7689702 · doi:10.1038/365061a0

  19. Bouaboula M, Poinot-Chazel C, Marchand J, et al. (1996). Signaling pathway associated with stimulation of CB2 peripheral cannabinoid receptor. Involvement of both mitogen-activated protein kinase and induction of Krox-24 expression. Eur J Biochem 237:704-11.

    PMID 8647116 · doi:10.1111/j.1432-1033.1996.0704p.x

  20. Shire D, Calandra B, Rinaldi-Carmona M, et al. (1996). Molecular cloning, expression and function of the murine CB2 peripheral cannabinoid receptor. Biochim Biophys Acta 1307:132-6.

    PMID 8679694 · doi:10.1016/0167-4781(96)00047-4

  21. PubChem computed properties (CID 104895)

Further Information