AMG-3.

AMG-3 is a classical cannabinoid built on the Δ8-THC skeleton, with a 1,3-dithiolane ring grafted at the C1' position of the side chain. Its affinity is sub-nanomolar, with a Ki of 0.32 nM at CB1 (rat brain) and 0.52 nM at CB2 (mouse spleen), higher than that reported for Δ8-THC. The conformational study by Mavromoustakos et al. (1999) indicates that the dithiolane ring restricts the orientation of the alkyl chain, which may account for this affinity. The phenol group of ring A remains indispensable: its methylated analogue AMG-18 is almost devoid of activity, a result that belongs to AMG-18 and not to AMG-3. In rats (1 to 8 mg/kg intraperitoneally), AMG-3 reduces spontaneous activity in a dose-dependent manner, induces catalepsy at the highest dose and lengthens the hot-plate reaction time for at least twenty-four hours; the effects of the highest dose on spontaneous activity and self-stimulation are entirely reversed by the CB1 antagonist AM-251, and the authors see in them no sign of abuse potential (Antoniou 2005). What remains unknown is considerable: intrinsic efficacy not quantified, no metabolism data, no human data, no clinical report.

Source

An entirely synthetic molecule, produced by no plant and existing only as a laboratory compound prepared in an academic pharmacology setting. Its name circulates online: a forum-crawling robot, active from 14 November 2017 to 31 May 2019, picked it up among 1,103 synthetic cannabinoids, without it being on the UNODC list (13 June 2019) or in the EMCDDA database (1 April 2019) (Zangani 2020). No seizure and no use in a consumer product is reported in the sources consulted.

No known biological pathway: AMG-3 derives from no plant biosynthesis. It is obtained by chemical synthesis and described here only by its class, that of Δ8-tetrahydrocannabinol analogues bearing a 1,3-dithiolane ring cyclic substituent at the C1' position of the side chain.

European Union

No Union-wide control measure targets AMG-3: it is not among the substances named in the annex of Framework Decision 2004/757/JHA as supplemented by Directives (EU) 2017/2103, 2019/369, 2020/1687, 2021/802, 2022/1326 and 2025/2062, nor in Schedule II of the 1971 Convention (Green List of the International Narcotics Control Board, 35th edition, 2024). The survey by Zangani et al. (2020), which compares the EMCDDA database as of 1 April 2019 and the UNODC list as of 13 June 2019 with forum mentions, places it outside both directories, among the structures discussed on the internet rather than among notified substances. Control therefore rests with each Member State.

France

AMG-3 is named nowhere in the consolidated list of ANSM (updated 16 February 2026). The entry “Tetrahydrocannabinols, their esters, ethers, salts and the salts of the aforementioned derivatives” (annex III since the decision of 6 February 2026) does not obviously designate it: it is an analogue of Δ8-THC with a modified side chain, neither an ester, an ether nor a salt of THC. It is, however, covered by the generic clause of annex IV stemming from the decisions of 22 May and 3 June 2024 (classification applicable from 3 June 2024): “any substance derived from the benzo[c]chromene nucleus”, non-, partially or fully hydrogenated on ring A, substituted notably “at position 1 by a hydroxyl function”, “at position 3 by an alkyl… chain”, whether that chain is itself substituted or not by cyclic or heterocyclic substituents, “at position 6 by one or two alkyl groups” and “at position 9 by a ketone, alkyl, hydroxyalkyl or alkoxy function”, excluding cannabinol, cannabinolic acid, THCV and THCVA below 0.3 % and THCA below the legal content. AMG-3, a tetrahydrobenzo[c]chromene bearing a hydroxyl at position 1, a hexyl chain substituted by a 1,3-dithiolane ring at position 3, two methyls at position 6 and a methyl at position 9, literally meets these criteria; this is a reading of the text and not a nominative decision of ANSM. It has no marketing authorisation and no status as a consumer product.

Sources: EUR-Lex, UNODC, CND, ANSM, IUPHAR/BPS, ChEBI, EUDA. Our method.

Family

Synthetic CB receptor agonist › Research ligand or medicine

Class

classical

Verification

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

Wikipedia (English)

AMG-3 (new tab)

Article paired by the molecule's structure (InChIKey), revision read on 19 October 2026. Read as a second opinion, never cited as a source.

1. 1Papahatjis et al., Journal of Medicinal Chemistry, 1998: pharmacophoric requirements for cannabinoid side chains, Δ8-THCs with multiple bonds and C1' substituents (dithiolane: CB1 Ki 0.32 nM, CB2 Ki 0.52 nM) (new tab)PMID 9544219
2. 2Mavromoustakos et al., Journal of Pharmaceutical and Biomedical Analysis, 1999: structure elucidation of AMG-3 and of its methylated analogue AMG-18 by 1D/2D NMR and modelling (new tab)PMID 9925329
3. 3Papahatjis et al., Journal of Medicinal Chemistry, 2003: pharmacophoric requirements for the cannabinoid side chain, C1' receptor subsite (dithiolane = potent CB1 agonist in vitro) (new tab)PMID 12852753
4. 4Antoniou et al., Behavioural Pharmacology, 2005: behavioural properties of the 1',1'-dithiolane analogue of Δ8-THC AMG-3 in the rat (1 to 8 mg/kg i.p., effects of the highest dose reversed by AM-251) (new tab)PMID 16148456
5. 5Mavromoustakos et al., Biochimica et Biophysica Acta, 2001: differential fluidisation of DPPC membranes by AMG-3 (active) and AMG-18 (inactive) (new tab)PMID 11406095
6. 6Durdagi et al., Bioorganic and Medicinal Chemistry, 2008: molecular dynamics simulations of AMG3 in solution and in the CB1 and CB2 binding site (new tab)PMID 18595717
7. 7ChEMBL, compound CHEMBL476325 (AMG-3): CB1 Ki 0.32 nM (rat forebrain synaptosomes) and CB2 Ki 0.52 nM (mouse spleen), document CHEMBL1131321 = J Med Chem 1998;41:1195 (new tab)
8. 8Zangani et al., Current Neuropharmacology, 2020: AMG-3 picked up by a forum web crawler (14 November 2017 - 31 May 2019), absent from the UNODC (13 June 2019) and EMCDDA (1 April 2019) lists (new tab)PMID 32116194
9. 9ANSM, consolidated list of substances classified as narcotics, updated 16 February 2026, annex IV: « any substance derived from the benzo[c]chromene nucleus » clause (decisions of 22 May and 3 June 2024) (new tab)
10. 10ANSM, ANSM adds new cannabinoids to the narcotics list, in force on 3 June 2024 (new tab)
11. 11INCB, Green List of psychotropic substances under international control, 35th edition, 2024 (Schedule II: AMG-3 absent) (new tab)
12. 12PubChem, compound CID 10002952 (AMG-3): identifiers, structure, CAS 179044-94-1 (new tab)

SMILES

CCCCCCC1(SCCS1)C2=CC3=C([C@@H]4CC(=CC[C@H]4C(O3)(C)C)C)C(=C2)O

Machine-readable entry (JSON)

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