Skip to content

Batch information on every product pageTHC < 0.3%Shipped from France10% off when you sign up

Synthetic

LEI-101

Peripherally restricted partial CB2 agonist, active by mouth in mice.

Unscheduled
Level of detail

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.

C₂₃H₂₅FN₄O₄S

CAS 1228660-00-1

Family
Synthetic CB receptor agonistResearch ligand or medicine
Molar mass
472.50 g/mol

Updated on

In plain terms

LEI-101 is a laboratory molecule with no link to hemp: it was designed to activate the CB2 receptor, found mostly on cells of the immune system, rather than the brain's CB1 receptor. In mice, given by mouth, it concentrates in the kidneys and liver and passes very little into the brain. The data cited are preclinical; it is not a consumer product.

Receptors and activity

Target network

CB2Partial agonistKi = 31.6 nM · humanhuman CB2 binding, pKi 7.5 ± 0.1 converted to nM; roughly 100-fold selectivity over CB1 (pKi below 5)
  • Activates
  • Binds or modulates

The lower the cited value, the closer the target sits to LEI-101: one ring per factor of 100. A target with no measured value stays on the edge.

Where these targets live

Where each target has been found in humans, according to the cited studies. The map shows the target, not an effect of LEI-101.

Brain, side view
Body, front view
Blood

CB2CB2 found in 5 regions of the body

  1. SpleendenseHighly abundant in the spleen1
  2. Immune cellspresentMainly B cells and natural killer cells1
  3. SkinpresentKeratinocytes, mast cells and nerve fibres2
  4. GutpresentImmune cells of the colonic mucosa3
  5. BonepresentPresent on osteoclasts4

Map sources

  1. Galiègue S et al. Expression of central and peripheral cannabinoid receptors in human immune tissues and leukocyte subpopulations. Eur J Biochem, 1995 (new tab)
  2. Ständer S et al. Distribution of cannabinoid receptor 1 (CB1) and 2 (CB2) on sensory nerve fibers and adnexal structures in human skin. J Dermatol Sci, 2005 (new tab)
  3. Wright K et al. Differential expression of cannabinoid receptors in the human colon: cannabinoids promote epithelial wound healing. Gastroenterology, 2005 (new tab)
  4. Rossi F et al. The endovanilloid/endocannabinoid system in human osteoclasts: possible involvement in bone formation and resorption. Bone, 2009 (new tab)

Cited values

  1. CB2Partial agonistKi = 31.6 nM · human58 out of 100

    Mukhopadhyay et al., Br J Pharmacol 2016 (new tab) · human CB2 binding, pKi 7.5 ± 0.1 converted to nM; roughly 100-fold selectivity over CB1 (pKi below 5)

  2. CB2Partial agonistEC50 = 251 nM · human43 out of 100

    Mukhopadhyay et al., Br J Pharmacol 2016 (new tab) · [35S]GTPγS binding, pEC50 6.6 ± 0.2 converted to nM, maximal effect 65 ± 8%

  3. CB2 (recrutement de la β-arrestine)Partial agonistEC50 = 100 nM · human50 out of 100

    Mukhopadhyay et al., Br J Pharmacol 2016 (new tab) · β-arrestin recruitment, pEC50 7.0 ± 0.3 converted to nM, maximal effect 41 ± 6%

  4. CB1Binding (function not established)no measured value cited
Bar length follows the measured value (Ki, Kd, EC50 or IC50), on one scale shared by every entry, from 100 µM to 0.1 nM. A target with no cited value has no bar.

Pharmacology

LEI-101 is a partial agonist of the cannabinoid CB2 receptor, from a series of biaryl imidazolidine-2,4-diones (van der Stelt et al. 2011). At human receptors, its pKi is 7.5 for CB2 against less than 5 for CB1, with partial activation in both pathways studied: 65% of the maximal effect in [35S]GTPγS binding (pEC50 6.6) and 41% in β-arrestin recruitment (pEC50 7.0) (Mukhopadhyay et al. 2016). In mice, the molecule has excellent oral bioavailability and reaches high concentrations in the kidney and liver, with minimal penetration into the brain; up to 60 mg/kg orally, it produced no central cannabinoid-type effect in the tetrad test. In a cisplatin nephrotoxicity model, 3 or 10 mg/kg (orally or intraperitoneally) dose-dependently prevented kidney dysfunction and morphological damage, with improved renal histopathology and attenuated oxidative stress and inflammation; these effects were absent in mice lacking CB2 (Mukhopadhyay et al. 2016). A related molecule of the series, LEI-102, was used in a cryo-EM study of the activated CB2 receptor (Li et al. 2023). All these data are preclinical.

Key sources.

History

Source
A synthetic molecule of the biaryl hydantoin (imidazolidine-2,4-dione) class, absent from cannabis and from any living organism. A pharmacological tool, studied as the hydrochloride.

Origin

Laboratory synthesis

No biosynthetic pathway: a synthetic molecule, a biaryl hydantoin unrelated to the pathway of hemp cannabinoids.

Classification

Family, origin and source verification

Family

Synthetic CB receptor agonist › Research ligand or medicine

Class

biaryl hydantoin

Verification

Classification, sources and binding values checked on 20 October 2026; text read against its sources and Wikipedia.

Wikipedia (English)

No dedicated article.

References

  1. Mukhopadhyay P et al., The novel, orally available and peripherally restricted selective cannabinoid CB2 receptor agonist LEI-101 prevents cisplatin-induced nephrotoxicity, Br J Pharmacol 2016 (new tab)PMID 26398481
  2. van der Stelt M et al., Discovery and optimization of 1-(4-(pyridin-2-yl)benzyl)imidazolidine-2,4-dione derivatives as a novel class of selective cannabinoid CB2 receptor agonists, J Med Chem 2011 (new tab)PMID 21923175
  3. Li X et al., Structural basis of selective cannabinoid CB2 receptor activation, Nat Commun 2023 (LEI-102, optimised series) (new tab)PMID 36922494
  4. ANSM, Consolidated list of substances classified as narcotics, updated 16 February 2026, annex IV (new tab)
  5. PubChem, compound CID 127021038 (LEI-101 hydrochloride; parent CID 46220324) (new tab)

Identifiers

Names

IUPAC name
3-cyclopropyl-1-[[4-[6-[(1,1-dioxo-1,4-thiazinan-4-yl)methyl]-5-fluoro-2-pyridinyl]phenyl]methyl]imidazolidine-2,4-dione
Other names
LEI 101 · LEI-101 hydrochloride · LEI 101 hydrochloride

Identifiers

Formula
C₂₃H₂₅FN₄O₄S
CAS
1228660-00-1
PubChem CID
46220324(new tab)
InChIKey
XUZTUGWOFAKLPB-UHFFFAOYSA-N
SMILES
C1CC1N2C(=O)CN(C2=O)CC3=CC=C(C=C3)C4=NC(=C(C=C4)F)CN5CCS(=O)(=O)CC5

Machine-readable entry (JSON)

LLM ingestion format: a structured superset of the entry (identifiers, binding, versioned legal status). Full corpus.