Minor phytocannabinoid
UnscheduledCBLACannabicyclolic acid
3-hydroxy-9,13,13-trimethyl-5-pentyl-8-oxatetracyclo[7.4.1.02,7.012,14]tetradeca-2(7),3,5-triene-4-carboxylic acid
Aliases.cannabicyclolic acid · CBL-C5 acid · CBLA-C5
The acidic form of cannabicyclol, arising from the photo-oxidation of CBCA; pharmacology undocumented.
Updated on
Level of detail
Identifiers
- Formula
- C₂₂H₃₀O₄
- Molar mass
- 358.50 g·mol⁻¹
- CAS
- -
- PubChem CID
- 71437560
- First described
- Décrit en 1972 par Yukihiro Shoyama, Reiko Oku, Tatsuo Yamauchi et Itsuo Nishioka dans Chemical and Pharmaceutical Bulletin, sous le titre « Cannabis. VI. Cannabicyclolic Acid ». Les auteurs l'ont isolé à partir de chanvre stocké récolté tôt en phase végétative, puis reproduit par irradiation ultraviolette de l'acide cannabichroménique. Ils concluent explicitement qu'il s'agit d'un produit de transformation et non d'un cannabinoïde original de la plante.
- Origin
- CBLA is not a constituent of the living plant. It results from the photo-oxidation of cannabichromenic acid (CBCA) under ultraviolet radiation, during drying or prolonged storage of the plant material. The reference review of cannabis constituents classes it among the three known compounds of the cannabicyclol type and states that it forms during natural irradiation of CBCA, which makes it a storage artefact rather than a natural cannabinoid. The levels encountered remain at trace order.
- InChIKey
- JVOHLEIRDMVLHS-UHFFFAOYSA-N
In plain terms
Cannabicyclolic acid, or CBLA, is the acidic form of cannabicyclol. It does not come directly from the living plant: it appears when another hemp acid, CBCA, is exposed to light during drying or storage. Only traces of it are found in older harvests, and its effects on the body have hardly ever been studied.
Receptors and activity
- CB1Agonist
- CB2Agonist
- 5-HT1AModulator
- Agonist
- Partial agonist
- Antagonist
- Modulator
- Inverse agonist
Hover over a row for the precise value (Ki, EC50…)
Subjective signature
Hover over an axis to read its definition.
- Calm8
- Clarity5
- Sleep6
- Appetite4
- High5
Editorial estimate, not clinical.
Pharmacology
No study has directly measured the affinity of CBLA for the cannabinoid receptors, and human data are entirely lacking. The only pharmacological indications available concern its neutral form, cannabicyclol: in a radioligand binding study published in 2025, CBL did not displace CP55940 from the CB1 receptor, acted at CB2 only at high concentration, and showed by contrast a marked affinity for the 5-HT1A receptor, behaving as a positive allosteric modulator of the response to serotonin. Nothing allows this profile to be transposed to CBLA, whose additional carboxylic acid function alters polarity and membrane passage. Like the other acidic cannabinoids, it is described at class level as poorly bioavailable by the oral route and susceptible to decarboxylation under the effect of heat. No activity at TRPV1, GPR55 or PPARγ has been reported, and no therapeutic benefit is established.
Key sources.
- Shoyama Y, Oku R, Yamauchi T, Nishioka I. Cannabis. VI. Cannabicyclolic Acid. Chem Pharm Bull. 1972;20(9):1927-1930.DOI 10.1248/cpb.20.1927
- Radwan MM, Chandra S, Gul S, ElSohly MA. Cannabinoids, Phenolics, Terpenes and Alkaloids of Cannabis. Molecules. 2021;26(9):2774.PMID 34066753
- An Unexpected Activity of a Minor Cannabinoid: Cannabicyclol (CBL) Is a Potent Positive Allosteric Modulator of Serotonin 5-HT1A Receptor. J Nat Prod. 2025;88(1):58-66.PMID 39811943
- PubChem, Cannabicyclolic acid, CID 71437560 (National Library of Medicine).
- Arrêté du 22 février 1990 fixant la liste des substances classées comme stupéfiants, annexe IV (Légifrance).
- Therapeutic potential of acidic cannabinoids: an update (revue en accès libre, PubMed Central).
Biosynthetic pathway
No enzymatic pathway leads to CBLA. The molecule forms by photochemical cyclisation of cannabichromenic acid, itself derived from cannabigerolic acid under the action of CBCA synthase. This final step is purely abiotic and depends on light exposure, which explains why CBLA accumulates in stored harvests and not in the fresh plant.
Legal framework
France
CBLA is named in no French text classifying narcotics. The applicable instrument, the decree of 22 February 1990 establishing the list of substances classified as narcotics, covers in annex IV “tetrahydrocannabinols, their esters, ethers and salts as well as the salts of the aforementioned derivatives”. CBLA is neither a tetrahydrocannabinol nor an ester, ether or salt of a tetrahydrocannabinol, so it does not fall within this generic clause either. The molecule is consequently unclassified in France. The general rules governing hemp and its products remain applicable, in particular the maximum delta-9-THC content permitted in finished products.
European Union
No cannabinoid other than the tetrahydrocannabinols appears in the schedules of the international conventions of 1961 and 1971, and CBLA appears on no European list of controlled substances. Its placing on the food market falls, however, within the novel foods framework, cannabinoids and Cannabis sativa extracts being considered to lack a significant history of consumption in the Union before May 1997. National regimes remain heterogeneous from one member state to another.
Sources: EUR-Lex, UNODC, CND, ANSM, IUPHAR/BPS, ChEBI, EUDA. Our method.
Structural classification
- Class
- Minor phytocannabinoid
- Origin
- CBLA is not a constituent of the living plant. It results from the photo-oxidation of cannabichromenic acid (CBCA) under ultraviolet radiation, during drying or prolonged storage of the plant material. The reference review of cannabis constituents classes it among the three known compounds of the cannabicyclol type and states that it forms during natural irradiation of CBCA, which makes it a storage artefact rather than a natural cannabinoid. The levels encountered remain at trace order.
- Status
- Unscheduled
Phytocannabinoïde de type cannabicyclol : squelette tétracyclique comportant un motif cyclobutane fusionné, issu du cannabichromène, avec une chaîne latérale pentyle et une fonction acide carboxylique portée par le noyau phénolique.
Pharmacokinetics
Aucune étude de pharmacocinétique n'a été publiée sur le CBLA, ni chez l'animal ni chez l'humain. Les revues consacrées aux cannabinoïdes acides décrivent pour cette classe une biodisponibilité orale faible, une demi-vie courte et une pénétration limitée dans le système nerveux central, la fonction acide carboxylique abaissant nettement la lipophilie par rapport aux formes neutres. Ces caractéristiques de classe ne remplacent pas des mesures propres à la molécule, qui font défaut.
Metabolism
Le métabolisme du CBLA n'a pas été caractérisé : aucune voie de phase I ou de phase II identifiée, aucun métabolite décrit, aucune contribution enzymatique documentée. La seule transformation bien établie est chimique et non enzymatique, la décarboxylation en cannabicyclol sous l'effet de la chaleur, réaction commune aux cannabinoïdes acides lors du chauffage ou du stockage prolongé.
Toxicology and risks
Aucune donnée de toxicologie n'existe pour le CBLA : pas d'étude de toxicité aiguë ou répétée, pas d'évaluation de génotoxicité, aucun cas clinique rapporté. Aucune agence sanitaire n'a évalué la molécule et aucun signal de sécurité n'a été publié, ce qui reflète l'absence d'études et non une innocuité démontrée. Les quantités présentes dans le chanvre restent de l'ordre de la trace, ce qui limite l'exposition sans dispenser de prudence.
Detection and analysis
Le CBLA s'analyse par chromatographie liquide couplée à la détection ultraviolette ou à la spectrométrie de masse, et figure dans plusieurs panels analytiques élargis de cannabinoïdes. La difficulté principale est isobarique : le CBLA partage sa formule brute et sa masse avec les acides tétrahydrocannabinolique, cannabidiolique et cannabichroménique, si bien que seule une séparation chromatographique soignée, appuyée sur un étalon de référence certifié, permet une attribution sans ambiguïté. Aucune méthode de dépistage validée en matrice biologique n'a été décrite pour cette molécule.
References
- 1.Shoyama Y, Oku R, Yamauchi T, Nishioka I. Cannabis. VI. Cannabicyclolic Acid. Chem Pharm Bull. 1972;20(9):1927-1930.DOI 10.1248/cpb.20.1927
- 2.Radwan MM, Chandra S, Gul S, ElSohly MA. Cannabinoids, Phenolics, Terpenes and Alkaloids of Cannabis. Molecules. 2021;26(9):2774.PMID 34066753
- 3.An Unexpected Activity of a Minor Cannabinoid: Cannabicyclol (CBL) Is a Potent Positive Allosteric Modulator of Serotonin 5-HT1A Receptor. J Nat Prod. 2025;88(1):58-66.PMID 39811943
- 4.PubChem, Cannabicyclolic acid, CID 71437560 (National Library of Medicine).
- 5.Arrêté du 22 février 1990 fixant la liste des substances classées comme stupéfiants, annexe IV (Légifrance).
- 6.Therapeutic potential of acidic cannabinoids: an update (revue en accès libre, PubMed Central).
Structured data
- InChIKey
- JVOHLEIRDMVLHS-UHFFFAOYSA-N
- SMILES
- CCCCCC1=CC2=C(C3C4C(C3(C)C)CCC4(O2)C)C(=C1C(=O)O)O
- Formula
- C22H30O4
- Molar mass
- 358.50 g·mol⁻¹
- PubChem CID
- 71437560
LLM ingestion format: a structured superset of the entry (identifiers, binding, versioned legal status). Full corpus.