HU-210

(6aR,10aR)-9-(hydroxymethyl)-6,6-dimethyl-3-(2-methyloctan-2-yl)-6a,7,10,10a-tetrahydrobenzo[c]chromen-1-ol

Overview

HU-210 belongs to Cannabinoids.

Key safety note: HU-210 is extraordinarily potent, active in microgram amounts, so the margin for error is tiny and accidental overdose is easy.[3]
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.
  • Broadly THC-like but far more intense: strong euphoria, deep relaxation or sedation, and marked alterations of perception, time sense and thought.
  • Adverse effects are common and can be severe given the potency: intense anxiety, paranoia and panic, acute psychosis, nausea and vomiting, dizziness, and pronounced tachycardia.
  • Effects are long-lasting compared with cannabis, and because active doses are so small, the gap between a 'normal' and an overwhelming dose is very narrow.
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
FormulaC25H38O3
Molar mass386.6 g/mol
StateNot reported
Melting pointNot reported
Boiling pointNot reported
DensityNot reported
Vapor pressureNot reported
pKaNot reported
LogP6.4 (predicted, XLogP3)
SolubilityNot reported
Refractive indexNot reported
Identifiers & Synonyms
CASNot reported
CAS (enantiomer)
PubChem CID9821569
InChIKeySSQJFGMEZBFMNV-WOJBJXKFSA-N
InChIInChI=1S/C25H38O3/c1-6-7-8-9-12-24(2,3)18-14-21(27)23-19-13-17(16-26)10-11-20(19)25(4,5)28-22(23)15-18/h10,14-15,19-20,26-27H,6-9,11-13,16H2,1-5H3/t19-,20-/m1/s1
SMILESCCCCCCC(C)(C)C1=CC(=C2[C@@H]3CC(=CC[C@H]3C(OC2=C1)(C)C)CO)O

Synonyms

    Pharmacodynamics & Biochemistry

    HU-210 ('Hebrew University-210') is a synthetic analogue of THC developed by Raphael Mechoulam's group. It is a classical (dibenzopyran) cannabinoid carrying a dimethylheptyl side chain and an 11-hydroxymethyl group, and it is the active (6aR,10aR) enantiomer: its mirror image, HU-211 (dexanabinol), is essentially inactive at cannabinoid receptors and instead acts as an NMDA antagonist. HU-210 is one of the most potent cannabinoid agonists known, on the order of 100-fold or more the potency of THC. Like THC it is an agonist at the CB1 and CB2 cannabinoid receptors, but with subnanomolar affinity and full (rather than partial) agonism at CB1. CB1 is a Gi/o-coupled receptor whose activation inhibits adenylyl cyclase and modulates ion channels. In HU-210's case this produces intense, THC-like effects, profound euphoria, sedation, altered perception and analgesia (and catalepsy in animals), that are far stronger and longer-lasting than THC's. HU-210 also engages non-classical cannabinoid targets: it is an agonist at the orphan receptor GPR55 and modulates glycine receptors, which may contribute to its overall pharmacology. The binding table below summarises these affinities. It is extremely lipophilic and long-acting. Because it is active in microgram amounts, HU-210 has appeared as an adulterant in illicit 'synthetic cannabis' ('Spice'/'K2') products, where uneven amounts can cause severe cannabinoid toxicity.

    Biological targets

    • CB1
    • CB2

    Binding & functional measurements

    TargetMeasurementSpecies
    CB1 receptorpKi 9.65Human
    CB2 receptorpKi 9.55Human
    GPR55pEC50 7.6Human
    Glycine Receptor (All subtypes)pEC50 6.6None
    glycine receptor α1 subunitpEC50 6.6Human
    Pharmacokinetics
    BioavailabilityNot established in humans (research chemical)
    TmaxNot reported
    Half-lifeNot established in humans, long-acting and highly lipophilic (effects far outlast THC in animal studies)
    VdNot reported
    Protein bindingNot reported
    MetabolismHepatic cannabinoid-type oxidative metabolism. Details not fully characterised
    ExcretionNot well characterised
    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

    HU-210 is extraordinarily potent, active in microgram amounts, so the margin for error is tiny and accidental overdose is easy. As an extremely strong, full CB1 agonist it can cause cannabinoid toxicity far beyond that of cannabis: intense anxiety and panic, acute psychosis, agitation, vomiting, dangerous tachycardia and blood-pressure changes, and prolonged incapacitation because of its long duration. It has no established safe human dose and is a research chemical, not a consumer product. It has turned up in illicit 'Spice'/'K2' blends, where unknown, uneven amounts have caused mass-poisoning outbreaks. Its effects and risks are largely extrapolated from THC and from other potent synthetic cannabinoids.[3]

    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 Additive sedation and impairment with alcohol and other CNS depressants.[3]
    Cannabis Additive and potentially severe CB1 effects with THC and other cannabinoids (marked tachycardia, anxiety, psychosis) given HU-210's extreme potency.[3]
    Stimulants (amphetamines, cocaine) Caution with stimulants and in cardiovascular or psychiatric conditions (tachycardia, anxiety, acute psychosis).[3]

    Contraindications

    Personal or family history of psychosis, schizophrenia or bipolar disorder history of psychosis, schizophrenia or bipolar disorder (cannabinoids can precipitate or worsen psychosis).[3]
    Cardiovascular disease, hypertension or arrhythmia tachycardia and blood-pressure effects.[3]
    Pregnancy or breastfeeding[3]
    Research chemical with no safety data (not for human consumption) a research chemical, not for human consumption, so avoid driving or operating machinery.[3]
    Usage & Context
    • Primarily a research chemical used in laboratory cannabinoid pharmacology as a potent, high-affinity CB1/CB2 agonist tool compound.
    • Has appeared as an adulterant in illicit 'synthetic cannabis' ('Spice'/'K2') products sold as smokable herbal blends.
    • Not a medicine and not a consumer recreational product with any established or reliable dosing.
    Sources & Evidence
    1. PubChem: HU-210 (CID 9821569) — identifiers & computed properties
    2. IUPHAR/BPS Guide to PHARMACOLOGY: HU-210 (ligand 731) — CB1/CB2, GPR55 and glycine-receptor binding data CC BY-SA 4.0
    3. 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

    4. Rhee MH, Vogel Z, Barg J, et al. (1997). Cannabinol derivatives: binding to cannabinoid receptors and inhibition of adenylylcyclase. J Med Chem 40:3228-33.

      PMID 9379442 · doi:10.1021/jm970126f

    5. 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

    6. Ryberg E, Larsson N, Sjögren S, et al. (2007). The orphan receptor GPR55 is a novel cannabinoid receptor. Br J Pharmacol 152:1092-101.

      PMID 17876302 · doi:10.1038/sj.bjp.0707460

    7. Wikipedia: HU-210 (chemistry, pharmacology & legal status) CC BY-SA 4.0
    8. DEA Diversion Control Division: Controlled Substance Schedules
    9. GOV.UK: Controlled drugs list (Misuse of Drugs legislation) OGL v3.0
    10. Pertwee RG, Howlett AC, Abood ME, et al. (2010). International Union of Basic and Clinical Pharmacology. LXXIX. Cannabinoid receptors and their ligands: beyond CB₁ and CB₂. Pharmacol Rev 62:588-631.

      PMID 21079038 · doi:10.1124/pr.110.003004

    11. 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

    12. Yang Z, Aubrey KR, Alroy I, et al. (2008). Subunit-specific modulation of glycine receptors by cannabinoids and N-arachidonyl-glycine. Biochem Pharmacol 76:1014-23.

      PMID 18755158 · doi:10.1016/j.bcp.2008.07.037

    13. PubChem computed properties (CID 9821569)

    Further Information