Synthetic cannabinoid (SCRA)
SynhexylParahexyl
Hexyl homologue of THC described in 1941, named as a narcotic in France.
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.
Receptors and activity
- CB1Modulator8 out of 100
Aucune constante d'affinité publiée ; aucune mesure d'activité retrouvée
- CB2Modulator8 out of 100
Aucune constante d'affinité publiée ; aucune mesure d'activité retrouvée
Subjective signature
- Calm
- 5 out of 100
- Relaxation of body and mind; reduced mental noise without marked drowsiness.
- Clarity
- 5 out of 100
- Sustained attention and clear thinking; functional lucidity, not euphoria.
- High
- 8 out of 100
- Euphoria and sensory intensity; altered perception of time and space.
- Appetite
- 8 out of 100
- Stimulation of hunger and of taste appreciation (the “munchies” effect).
- Sleep
- 8 out of 100
- Sedative effect: aids sleep onset and the continuity of deep sleep.
Pharmacology
Synhexyl, also called parahexyl, is a homologue of tetrahydrocannabinol with a hexyl side chain, linked to the work of Roger Adams and his collaborators on THC homologues published in 1941. Several publications, between 1948 and 1970, describe it in humans, including a direct comparison with THC in 1968. No affinity constant for CB1 or CB2 is published, and no measurement of its activity at these receptors has been found. It is named as a narcotic in the French list of narcotics, annex III, and appears in Schedule I of the 1971 Convention on Psychotropic Substances.
Key sources.
- Adams R., Loewe S., Jelinek C. et Wolff H., Homologues du tétrahydrocannabinol à activité marihuana, IX, Journal of the American Chemical Society, 1941 (new tab)DOI 10.1021/ja01852a052
- Williams E. G. et Himmelsbach C. K., Études sur la marihuana et le composé pyrahexyl, Public Health Reports, 1946 (new tab)PMID 20992145
- Pond D. A., Effets psychologiques du synhexyl chez des patients dépressifs, Journal of Neurology, Neurosurgery and Psychiatry, 1948 (new tab)PMID 18894648
- Thompson L. J. et Proctor R. C., Emploi du pyrahexyl dans les états de sevrage alcoolique et médicamenteux, North Carolina Medical Journal, 1953 (new tab)PMID 13099650
- Hollister L. E., Richards R. K. et Gillespie H. K., Comparaison du tétrahydrocannabinol et du synhexyl chez l'humain, Clinical Pharmacology and Therapeutics, 1968 (new tab)PMID 5721981
- Hollister L. E., Moore F., Kanter S. et Noble E., Δ1-tétrahydrocannabinol, synhexyl et extrait de marihuana administrés par voie orale chez l'humain : catécholamines, cortisol et sérotonine plaquettaire, Psychopharmacologia, 1970 (new tab)PMID 5523370
- ANSM, Liste consolidée des substances classées comme stupéfiants, mise à jour du 16 février 2026 (annexe III, parahexyl) (new tab)
- OICS, Liste verte (Green List) des substances psychotropes sous contrôle international, tableau I, code PP 001 (parahexyl) (new tab)
- PubChem CID 8334 : synhexyl (identifiants et masse moléculaire) (new tab)
- Parahexyl, article Wikipedia (repère tertiaire) (new tab)
History
- Source
- Synthetic molecule, created in the laboratory to study homologues of tetrahydrocannabinol. No natural occurrence is recorded.
Origin (pharmaceutical research → illicit market)
No biosynthetic pathway is described: the compound is obtained by chemical synthesis, and a 1968 study (Hollister et al.) describes it as semisynthetic.
Legal framework
- European Union
At European Union level there is no harmonised control measure targeting this compound: control is a matter for the Member States.
- France
Named as a narcotic in France: parahexyl appears in annex III of the consolidated list of narcotics, updated on 16 February 2026, under the order of 22 February 1990, as amended by the order of 24 March 2000. Parahexyl is preceded by an asterisk in that list, which extends the classification to its stereoisomers where they can exist under the chemical designation given. The list is drawn up under article L. 5132-7 of the French Public Health Code.
Sources: EUR-Lex, UNODC, CND, ANSM, IUPHAR/BPS, ChEBI, EUDA. Our method.
References
- Adams R., Loewe S., Jelinek C. et Wolff H., Homologues du tétrahydrocannabinol à activité marihuana, IX, Journal of the American Chemical Society, 1941 (new tab)DOI 10.1021/ja01852a052
- Williams E. G. et Himmelsbach C. K., Études sur la marihuana et le composé pyrahexyl, Public Health Reports, 1946 (new tab)PMID 20992145
- Pond D. A., Effets psychologiques du synhexyl chez des patients dépressifs, Journal of Neurology, Neurosurgery and Psychiatry, 1948 (new tab)PMID 18894648
- Thompson L. J. et Proctor R. C., Emploi du pyrahexyl dans les états de sevrage alcoolique et médicamenteux, North Carolina Medical Journal, 1953 (new tab)PMID 13099650
- Hollister L. E., Richards R. K. et Gillespie H. K., Comparaison du tétrahydrocannabinol et du synhexyl chez l'humain, Clinical Pharmacology and Therapeutics, 1968 (new tab)PMID 5721981
- Hollister L. E., Moore F., Kanter S. et Noble E., Δ1-tétrahydrocannabinol, synhexyl et extrait de marihuana administrés par voie orale chez l'humain : catécholamines, cortisol et sérotonine plaquettaire, Psychopharmacologia, 1970 (new tab)PMID 5523370
- ANSM, Liste consolidée des substances classées comme stupéfiants, mise à jour du 16 février 2026 (annexe III, parahexyl) (new tab)
- OICS, Liste verte (Green List) des substances psychotropes sous contrôle international, tableau I, code PP 001 (parahexyl) (new tab)
- PubChem CID 8334 : synhexyl (identifiants et masse moléculaire) (new tab)
- Parahexyl, article Wikipedia (repère tertiaire) (new tab)
Structured data
- SMILES
- CCCCCCC1=CC2=C(C3=C(CCC(C3)C)C(O2)(C)C)C(=C1)O
- InChIKey
- OORFXDSWECAQLI-UHFFFAOYSA-N
LLM ingestion format: a structured superset of the entry (identifiers, binding, versioned legal status). Full corpus.