CP 50,556-1Levonantradol
Synthetic cannabinoid of the nantradol family that binds CB1, evaluated in clinical trials during the 1980s.
C₂₇H₃₆ClNO₄
Harm-reduction warning
No characterised human dose: animal / in vitro data only. Effect profile, safety margin and acute toxicity are not documented in human clinical practice. Extremely potent compound: severe effects, seizures and deaths reported in the literature.
Data sheet
Names
- Common name
- Levonantradol
- IUPAC name
- [(6S,6aR,9R,10aR)-9-hydroxy-6-methyl-3-[(2R)-5-phenylpentan-2-yl]oxy-5,6,6a,7,8,9,10,10a-octahydrophenanthridin-1-yl] acetate;hydrochloride
- Other names
- Levonantradol HCl · Levonantradol hydrochloride · CP-50556-1 · CP 50556-1 hydrochloride · DA-52090
Identifiers
- Formula
- C₂₇H₃₆ClNO₄
- Molar mass
- 474.00 g/mol
- PubChem CID
- 5361880(new tab)
- InChIKey
- NSOGAHPJIFTUHV-YINRMENDSA-N
Class
- Family
- Synthetic cannabinoid (SCRA)
Updated on
Receptors and activity
- CB1Agonist90 out of 100
Ki 2,9 nM sur le CB1 de rat, déplacement de [3H]SR141716A (valeur répertoriée par ChEMBL, issue de Han et coll., 2013)
Subjective signature
- Calm
- 55 out of 100
- Relaxation of body and mind; reduced mental noise without marked drowsiness.
- Clarity
- 10 out of 100
- Sustained attention and clear thinking; functional lucidity, not euphoria.
- High
- 5 out of 100
- Euphoria and sensory intensity; altered perception of time and space.
- Appetite
- 10 out of 100
- Stimulation of hunger and of taste appreciation (the “munchies” effect).
- Sleep
- 25 out of 100
- Sedative effect: aids sleep onset and the continuity of deep sleep.
Pharmacology
Levonantradol (CP 50,556-1) is a synthetic cannabinoid of the nantradol family, whose levorotatory enantiomer is the active form. In mice, given intravenously, it is active between 0.123 and 1.5 mg/kg, whereas the dextrorotatory enantiomer is inactive (Little et al., 1988). It has an affinity (Ki) of 2.9 nM for rat CB1, a value listed in ChEMBL. Tested in chemotherapy and postoperative pain patients during the 1980s, it notably caused drowsiness, dizziness, hypotension and pain at the injection site as side effects; no data on non-medical use are published in the sources consulted.
Key sources.
- Little et coll., stéréosélectivité de cannabinoïdes structurellement nouveaux chez la souris, J Pharmacol Exp Ther 1988 (new tab)PMID 2849657
- Howlett et Fleming, inhibition de l'adénylate cyclase dans des membranes de neuroblastome, Mol Pharmacol 1984 (new tab)PMID 6092901
- Han et coll., utilité thérapeutique des agonistes sélectifs du CB2, J Med Chem 2013 (new tab)PMID 23865723
- Shepard, pharmacocinétique du levonantradol chez l'animal et l'humain, J Clin Pharmacol 1981 (new tab)PMID 7298868
- Tyson et coll., essai de phase I du levonantradol dans les nausées induites par la chimiothérapie, Am J Clin Oncol 1985 (new tab)PMID 4083271
- Citron et coll., efficacité antiémétique du levonantradol comparée au delta-9-THC, Cancer Treat Rep 1985 (new tab)PMID 2981616
- Joss et coll., levonantradol, antiémétique à taux élevé d'effets indésirables, Cancer Chemother Pharmacol 1982 (new tab)PMID 7139853
- Stambaugh et coll., évaluation de doses croissantes de levonantradol intramusculaire, J Clin Pharmacol 1984 (new tab)PMID 6392353
- Jain et coll., levonantradol intramusculaire et placebo dans la douleur postopératoire aiguë, J Clin Pharmacol 1981 (new tab)PMID 7028791
- Sheshenev et coll., synthèse asymétrique et analyse structurale du levonantradol, Chem Commun 2013 (new tab)PMID 23535893
- Milne et coll., activité analgésique stéréospécifique du nantradol, NIDA Res Monogr 1979 (new tab)PMID 121368
- ANSM, liste consolidée des stupéfiants, mise à jour du 16 février 2026 (new tab)
- INCB, Green List 2026 (conventions de 1971) (new tab)
- PubChem, CID 5361880 (chlorhydrate de levonantradol) (new tab)
- ChEMBL, CHEMBL2111116 (données d'activité CB1) (new tab)
- Wikipédia, Levonantradol (repère tertiaire) (new tab)
History
- Source
- Levonantradol (CP 50,556-1) is a synthetic cannabinoid of the nantradol family, a structurally novel compound related to cannabinoids (Milne et al., 1979). It forms an enantiomeric pair with dextronantradol, which is inactive in mice (Little et al., 1988). An encyclopedic source attributes its development to Pfizer (tertiary reference, Wikipedia); no primary source consulted confirms this.
Origin (pharmaceutical research → illicit market)
No biosynthetic pathway: a synthetic chemical compound of the octahydrophenanthridine family, with no published natural equivalent in the sources consulted.
Legal framework
- European Union
At European Union level, no harmonised control measure has been identified for this molecule in the sources consulted; control falls under national law.
- France
Levonantradol is not named in the ANSM consolidated list of narcotics (update of 16 February 2026) and does not appear in the INCB Green List 2026 (1971 Convention schedules). Its structure does not meet the definition of cyclohexylphenols or 2-(3-hydroxycyclohexyl)phenol derivatives, because the substituent at position 5 of the phenol ring is an ether (O-alkyl) rather than an alkyl group bonded directly to the ring. It also does not meet the tetrahydrocannabinol definition (ministerial order of 22 February 1990) or the benzo[c]chromene definition (decision of 22 May 2024), its core being nitrogenous.
Sources: EUR-Lex, UNODC, CND, ANSM, IUPHAR/BPS, ChEBI, EUDA. Our method.
References
- Little et coll., stéréosélectivité de cannabinoïdes structurellement nouveaux chez la souris, J Pharmacol Exp Ther 1988 (new tab)PMID 2849657
- Howlett et Fleming, inhibition de l'adénylate cyclase dans des membranes de neuroblastome, Mol Pharmacol 1984 (new tab)PMID 6092901
- Han et coll., utilité thérapeutique des agonistes sélectifs du CB2, J Med Chem 2013 (new tab)PMID 23865723
- Shepard, pharmacocinétique du levonantradol chez l'animal et l'humain, J Clin Pharmacol 1981 (new tab)PMID 7298868
- Tyson et coll., essai de phase I du levonantradol dans les nausées induites par la chimiothérapie, Am J Clin Oncol 1985 (new tab)PMID 4083271
- Citron et coll., efficacité antiémétique du levonantradol comparée au delta-9-THC, Cancer Treat Rep 1985 (new tab)PMID 2981616
- Joss et coll., levonantradol, antiémétique à taux élevé d'effets indésirables, Cancer Chemother Pharmacol 1982 (new tab)PMID 7139853
- Stambaugh et coll., évaluation de doses croissantes de levonantradol intramusculaire, J Clin Pharmacol 1984 (new tab)PMID 6392353
- Jain et coll., levonantradol intramusculaire et placebo dans la douleur postopératoire aiguë, J Clin Pharmacol 1981 (new tab)PMID 7028791
- Sheshenev et coll., synthèse asymétrique et analyse structurale du levonantradol, Chem Commun 2013 (new tab)PMID 23535893
- Milne et coll., activité analgésique stéréospécifique du nantradol, NIDA Res Monogr 1979 (new tab)PMID 121368
- ANSM, liste consolidée des stupéfiants, mise à jour du 16 février 2026 (new tab)
- INCB, Green List 2026 (conventions de 1971) (new tab)
- PubChem, CID 5361880 (chlorhydrate de levonantradol) (new tab)
- ChEMBL, CHEMBL2111116 (données d'activité CB1) (new tab)
- Wikipédia, Levonantradol (repère tertiaire) (new tab)
Structured data
- SMILES
- C[C@H]1[C@@H]2CC[C@H](C[C@H]2C3=C(N1)C=C(C=C3OC(=O)C)O[C@H](C)CCCC4=CC=CC=C4)O.Cl
- InChIKey
- NSOGAHPJIFTUHV-YINRMENDSA-N
LLM ingestion format: a structured superset of the entry (identifiers, binding, versioned legal status). Full corpus.