generation run 2026-05-07
66 min completedmodel pipeline-v5plan not recordedrun/d1ced13c…Selection
Verification
- record
- seen / partial
- working
The model's own caveats
- sparse_evidence
- structural_inference
Reproduce
- inputs
- 26 source keys (listed under Sources)
- plan
- not recorded — template version, prompt hash and git SHA are written from 2026-09 onward
- model
- pipeline-v5
- streams
- none — agent transcripts are persisted from 2026-09 onward
17 searches — query, source, results, what was kept and why
| # | source | query | seen | kept | rationale |
|---|---|---|---|---|---|
| 1 | PubMed | HHC hexahydrocannabinol metabolism urine detection | 15 | 9 | All directly relevant to HHC pharmacokinetics, metabolism, and forensic detection |
| 2 | OpenAlex | hexahydrocannabinol HHC cannabinoid | 173 | 6 | All directly relevant to HHC chemistry, pharmacology, and analysis |
| 3 | PubMed · absence | hexahydrocannabinol synthesis Adams 1940 | 0 | — | — |
| 4 | PubMed · absence | hexahydrocannabinol HHC pharmacology receptor binding | 0 | — | — |
| 5 | PubChem | hexahydrocannabinol | 1 | 1 | Canonical reference stereoisomer (9R-HHC). Note: the 9S epimer has a different CID. |
| 6 | PubMed | hexahydrocannabinol CB1 cannabinoid receptor agonist tetrad mouse | 2 | 2 | Relevant to CB1 pharmacology and HHC analog structure-activity |
| 7 | PubMed | HHC HHCP hemp-derived cannabinoid product analysis market | 1 | 1 | Critical pharmacological data: CB1 activity comparison between HHC epimers and THC |
| 8 | OpenAlex | HHC hexahydrocannabinol new psychoactive substance forensic seizure market | 23 | 5 | Animal toxicology, clinical case reports, and market context |
| 9 | WebSearch | hexahydrocannabinol Adams Loewe 1940 1941 first synthesis history marijuana | 10 | 3 | — |
| 10 | WebSearch | HHC hexahydrocannabinol legal status United States Europe UK scheduling | 10 | 3 | — |
| 11 | WebSearch | HHC DEA Schedule I drug code 2026 | 10 | 2 | — |
| 12 | PubMed | studies pertaining emerging cannabinoid hexahydrocannabinol HHC 2023 | 1 | 1 | Key receptor pharmacology paper with both binding and functional activity data; plus commercial product analysis |
| 13 | WebSearch | WHO ECDD 47th expert committee HHC scheduling recommendation 2024 | 10 | 3 | — |
| 14 | PubMed | hexahydrocannabinol on light cannabis market hemp | 1 | 1 | Documents natural HHC occurrence and commercial product composition |
| 15 | OpenAlex | HHC hexahydrocannabinol CB1 receptor binding affinity Ki EC50 potency | 4 | 1 | Most specific CB1 receptor activity data available for HHC epimers |
| 16 | federal_register | DEA Schedule I drug code HHC | 1 | 1 | — |
| 17 | PubMed/OpenAlex combined | synthesis of research output from all gathered sources | 45 | 1 | Comprehensive research across all relevant domains for HHC article generation |
66 claims by section — every cited sentence, checked against its source
safety18 · 17 ok
Semi-synthetic production may introduce unreacted Δ⁸/Δ⁹-THC, reaction intermediates, and catalyst residuessupported
Discusses HHC, unlabeled synthesis byproducts, product contamination risks, and regulatory gaps. 000536339
Variable (9R):(9S) epimer ratios (0.2:1 to 2.4:1) produce batch-to-batch potency inconsistencysupported
Examination of 60+ commercial HHC products: wide variability in (9R):(9S) ratio (0.2:1 to 2.4:1). acschembio.3c00254
A 1:1 (9R):(9S) mixture was administered intragastrically to male Wistar rats under OECD 423 protocol, classifying HHC as a Category 4 substance with an estimated LD₅₀ of approximately 1000 mg/kg (oral, rat)supported
1:1 mixture of (9R)- and (9S)-HHC administered intragastrically at 1, 5, 10 mg/kg in male Wistar rats. OECD 423 toxicity test classified HHC as Category 4, estimated LD50 1000 mg/kg. pyaf041
HHC-C8 (octyl homolog): Two patients hospitalized after HHC-C8 intoxication. Case 1: young male, deep unconsciousness with recurring seizures, coma lasting 2 days, gradual recovery over 2 weeks; HHC-C8 blood concentration 72 ng/mL at admission. Case 2: female, prolonged sedation, minimally responsive for 3 days. The product contained 6–7% HHC-C8.supported
Case 1: young male found unconscious, recurring seizures, coma for 2 days, slow improvement over 2 weeks. HHC-C8 blood concentration 72 ng/mL at admission. Case 2: female with 14 hours sleep and minimally responsive state, pronounced somnolence/sedation for 3 days. Product contained 6-7% HHC-C8. j.toxrep.2025.101912
HHC-C9 (nonanyl homolog): Male in early 40s admitted after ingestion of 40 mg HHC-C9; symptoms included vomiting, visual disturbances, and 9 days of cognitive and physical impairment.supported
Male in early 40s admitted to ED after ingestion of cannabis cookies (40mg HHC-C9)... Vomiting, visual problems, 9 days of cognitive and physical impairment. reports8030176
Claim in safety — inconclusiveinconclusiveworking →
For pentyl-chain HHC itself, the controlled human pilot studies documented psychomotor impairment after inhalation (one of three participants showed "distinct impairments") and after oral administration (psychophysical test impairment documented), but sample sizes (n = 3 per group) preclude systematic adverse event characterization.supported
three participants per group... Overall, the pharmacokinetics and effects of HHC were comparable to THC. Route of administration and inter-individual factors were crucial. s41598-025-93931-4
Anxiety and paranoia are documented as dose-dependent effects in the rat behavioral model (increased anxiety-like behavior at 10 mg/kg in the open field test) and reported by userssupported
10 mg/kg reduced movement, increased anxiety, impaired sensory processing. pyaf041
The 2024 European Web Survey on Drugs documented reports of psychotic illness precipitated by HHC use in Ireland, though no formal case series has been publishedsupported
Reports of psychotic illness precipitated by HHC use. Study aimed to measure extent of HHC use and patterns of use among adults in Ireland who use drugs. j.drugpo.2025.105011
Acute cognitive impairment — including impaired sensorimotor gating (documented in rats), psychomotor impairment (documented in human pilot studies), and memory disruption (inferred from CB1 hippocampal pharmacology) — occurs during active intoxicationsupported
10 mg/kg reduced movement, increased anxiety, impaired sensory processing. pyaf041
Acute cognitive impairment — including impaired sensorimotor gating (documented in rats), psychomotor impairment (documented in human pilot studies), and memory disruption (inferred from CB1 hippocampal pharmacology) — occurs during active intoxicationsupported
Overall, the pharmacokinetics and effects of HHC were comparable to THC. Route of administration and inter-individual factors were crucial. s41598-025-93931-4
Acute cognitive impairment — including impaired sensorimotor gating (documented in rats), psychomotor impairment (documented in human pilot studies), and memory disruption (inferred from CB1 hippocampal pharmacology) — occurs during active intoxicationsupported
Cannabimimetic effects: vertigo, headache, dizziness, dry mouth. j.forsciint.2025.112437
The Ireland Web Survey on Drugs documented HHC use patterns but did not publish quantitative dependence data.supported
Study aimed to measure extent of HHC use and patterns of use among adults in Ireland who use drugs. j.drugpo.2025.105011
Δ⁹-THC and CBD inhibit CYP2C9, CYP2C19, and CYP3A4partially supported
Nearly all inhibit CYP2C9 (Ki 0.2-3.2 μM). Most inhibit CYP2C19. Limited effects on CYP2D6, CYP3A4, CYP2B6. s12248-021-00616-7
Δ⁹-THC and CBD inhibit CYP2C9, CYP2C19, and CYP3A4partially supported
CBD+THC brownie inhibited CYP2C19>CYP2C9>CYP3A>CYP1A2. THC alone did not significantly inhibit any CYP. cpt.2973
Other cannabinoids: pharmacodynamic summation at CB1; particularly relevant given that commercial HHC products may contain residual Δ⁸/Δ⁹-THC from the synthesis processsupported
Discusses HHC, unlabeled synthesis byproducts, product contamination risks, and regulatory gaps. 000536339
Personal or family history of psychotic disorders: CB1 agonism is an established risk factor for precipitation and exacerbation of psychotic illness. HHC-precipitated psychosis reports from Ireland support this risk.supported
Reports of psychotic illness precipitated by HHC use. j.drugpo.2025.105011
Anxiety disorders: dose-dependent anxiogenesis documented in animal models; patients with panic disorder or generalized anxiety disorder may experience symptom exacerbation.supported
10 mg/kg reduced movement, increased anxiety, impaired sensory processing. pyaf041
pharmacokinetic-detail9 · 7 ok
In the rat model, a 1:1 (9R):(9S) mixture administered intragastrically at 1, 5, and 10 mg/kg to male Wistar rats produced peak blood and brain concentrations at 2 hours post-administration at the 10 mg/kg dose, confirming that HHC readily crosses the blood-brain barrier.supported
1:1 mixture of (9R)- and (9S)-HHC administered intragastrically at 1, 5, 10 mg/kg in male Wistar rats. Peak concentrations 2h after highest dose in blood and brain. HHC crosses BBB. pyaf041
Claim in pharmacokinetic-detail — inconclusiveinconclusiveworking →
HHC undergoes Phase I and Phase II metabolism similar to that of Δ⁹-THC.supported
HHC undergoes biotransformation similar to delta9-THC. Phase I reactions involve oxidation of C11 and pentyl side chain... Extensive glucuronidation of HHC and Phase I metabolites evident. bkae022
HHC undergoes Phase I and Phase II metabolism similar to that of Δ⁹-THC.supported
HHC primarily metabolized through monohydroxylation, followed by oxidation to carboxylic acid... 99.3% of hydroxylated metabolites glucuronidated. dta.3740
The HHC parent compound is detectable in plasma but not typically in urinesupported
HHC itself only detectable in plasma, not urine. bkae022
A serum cutoff of ≥30% (9R)-HHC-COOH relative to total THC-COOH has been proposed to distinguish HHC consumption from THC-alone use.supported
recommends 30% (9R)-HHC-COOH/THC-COOH ratio in serum as cutoff. j.jpba.2025.116833
In Sweden, following HHC's market appearance in 2022, false-positive THC oral fluid screening rates rose from less than 2% to over 10%supported
HHC appeared in Sweden in 2022. By spring 2023, false positive THC screening tests rose from <2% to >10% due to HHC cross-reactivity. 00365513.2024.2340039
Specific cross-reactivity findings: DrugScreen urine panels (25 ng/mL THC-COOH cutoff) cross-react with HHC metabolites; DrugWipe 5S oral fluid devices do not cross-react.partially supported
Explains false-positive THC immunoassay screens that were GC-MS negative for THC-COOH. 00365513.2024.2333023
Claim in pharmacokinetic-detail — inconclusiveinconclusiveworking →
pharmacology9 · 9 ok
The (9R)-epimer displays an EC₅₀ of 53.4 nM in functional CB1 agonism assays, comparable to Δ⁹-THC, while the (9S)-epimer yields an EC₅₀ of 624.3 nM — approximately 12-fold less potentsupported
9R-HHC EC50 = 53.4 nM (partial agonist); 9S-HHC EC50 = 624.3 nM (~12x less potent partial agonist). delta9-THC and 9R-HHC showed comparable CB1 binding poses. ph17050637
Binding affinity for both epimers has been described qualitatively as 'similar to Δ⁹-THC' in radioligand competition contexts, though no published Ki value from a displacement assay exists for unmodified HHC.supported
(9R)-HHC binding affinity and activity similar to delta9-THC. (9S)-HHC binds strongly but displays diminished activity in functional assays. acschembio.3c00254
Molecular mechanics analysis demonstrated that the (9R) (11β) configuration constrains the carbocyclic C-ring into a chair conformation that positions the C9 methyl group equatorially, an orientation critical for productive engagement with the CB1 binding pocketsupported
11-beta-HHC is active; 11-alpha-HHC is minimally active. Molecular mechanics calculations show that carbocyclic ring conformation determines orientation relative to phenyl group hydroxyl. pmid:2738895
The (9S) (11α) configuration permits alternative ring conformations (chair or twist) in which the C9 substituent adopts a less favorable spatial relationship to the receptor.supported
11-alpha-HHC is minimally active. Molecular mechanics calculations show that carbocyclic ring conformation determines orientation relative to phenyl group hydroxyl. pmid:2738895
The (9S) (11α) configuration permits alternative ring conformations (chair or twist) in which the C9 substituent adopts a less favorable spatial relationship to the receptor.supported
9S-HHC adopted different binding posture explaining weak activity. ph17050637
In a β-arrestin2 CB1 recruitment bioassay, HHC exhibited higher CB1 activation potential than Δ⁹-THC based on either higher Emax or greater potencysupported
HHC and HHCP identified as having higher CB1 activation potential than delta9-THC based on efficacy or potency. s00204-024-03769-4
Höfert and colleagues administered 25 mg HHC orally (fruit gum) and via inhalation (3 puffs from a vape device) to three participants per group, sampling serum for up to 48 hours and urine for 5 dayssupported
oral (25 mg HHC fruit gum) and inhalative (three puffs from HHC vape) consumption with three participants per group. Serum, urine, and saliva collected up to 48h and 5 days respectively. s41598-025-93931-4
Lucuta and colleagues measured plasma concentrations after oral administration of 25 mg HHC and inhalation of a 95% HHC vape productsupported
inhalation (95% HHC vape) vs oral (25 mg HHC gummies). Peak (9R)-HHC plasma ~65 ng/mL at 0.08h after inhalation; ~3.8 ng/mL at 1.16h after oral. j.forsciint.2025.112437
In a forensic case series of 599 serum samples from suspected cannabis users, 25 were HHC-positive, with (9R)-HHC concentrations of 0.15–14.4 ng/mL and (9S)-HHC concentrations of 0.14–5.76 ng/mL.partially supported
GC-MS method validated for HHC epimers in 599 serum samples from forensic cases. HHC only, n=6; HHC+THC, n=19; THC only, n=574. (9R)-HHC serum concentrations 0.15-14.4 ng/mL. j.jpba.2025.116833
chemistry5 · 4 ok
Claim in chemistry — inconclusiveinconclusiveworking →
Commercially, HHC is synthesized from hemp-derived CBD via a two-step process: acid-catalyzed cyclization to Δ⁸/Δ⁹-THC followed by catalytic hydrogenation.supported
Current large-scale manufacture of HHC is based on hemp-derived CBD extract, converted by cyclization into delta8/delta9-THC mixture, followed by catalytic hydrogenation to afford a mixture of (9R)-HHC and (9S)-HHC epimers. dta.3519
(9R)-HHC (also designated 11β-HHC or "beta-HHC"): the pharmacologically active epimer. Molecular mechanics modeling demonstrates that the (9R) configuration produces a chair conformation of the carbocyclic C-ring that orients the C9 methyl substituent in the equatorial position, a geometry essential for optimal CB1 receptor engagement.supported
11-beta-HHC is active; 11-alpha-HHC is minimally active. Molecular mechanics calculations show that carbocyclic ring conformation determines orientation relative to phenyl group hydroxyl. pmid:2738895
Commercial products, however, contain widely variable ratios — analysis of over 60 products found (9R):(9S) ratios ranging from 0.2:1 to 2.4:1.supported
Examination of 60+ commercial HHC products: wide variability in (9R):(9S) ratio (0.2:1 to 2.4:1). acschembio.3c00254
Casati and colleagues were among the first to document and quantify both epimers in commercialized hemp-derived products, reporting 42.5% (9R)-HHC and 23.6% (9S)-HHC by weight in resin samples (with the remaining content composed of other cannabinoids and carrier substances)supported
First description of (9R)-HHC and (9S)-HHC in commercialized hemp-derived products. Commercial samples showed 42.5% (9R)-HHC and 23.6% (9S)-HHC. can.2022.0253
comparative-pharmacology5 · 3 ok
Case reports of severe adverse events from these homologs — including coma lasting 2 days (HHC-C8, blood concentration 72 ng/mL) and 9 days of cognitive and physical impairment (HHC-C9, 40 mg ingested) — should not be directly extrapolated to pentyl-chain HHCsupported
Case 1: young male found unconscious, recurring seizures, coma for 2 days, slow improvement over 2 weeks. HHC-C8 blood concentration 72 ng/mL at admission. j.toxrep.2025.101912
Case reports of severe adverse events from these homologs — including coma lasting 2 days (HHC-C8, blood concentration 72 ng/mL) and 9 days of cognitive and physical impairment (HHC-C9, 40 mg ingested) — should not be directly extrapolated to pentyl-chain HHCsupported
Male in early 40s admitted to ED after ingestion of cannabis cookies (40mg HHC-C9)... 9 days of cognitive and physical impairment. reports8030176
The primary pharmacological distinction between HHC and Δ⁹-THC is not potency — which is comparable for the (9R)-epimer — but rather the diastereomeric composition of commercial products. Δ⁹-THC exists as a single stereochemically defined species, whereas commercial HHC is invariably a mixture of the active (9R) and weakly active (9S) epimers in ratios that vary from 0.2:1 to 2.4:1supported
(9R)-HHC binding affinity and activity similar to delta9-THC... wide variability in (9R):(9S) ratio (0.2:1 to 2.4:1). acschembio.3c00254
Claim in comparative-pharmacology — inconclusiveinconclusiveworking →
Claim in comparative-pharmacology — inconclusiveinconclusiveworking →
receptor-pharmacology5 · 4 ok
Claim in receptor-pharmacology — inconclusiveinconclusiveworking →
The (9S)-epimer retains measurable binding affinity in some displacement-type assays but shows markedly diminished functional efficacy, suggesting a binding mode that produces less efficient receptor activation.supported
9S-HHC EC50 = 624.3 nM (~12x less potent partial agonist). 9S-HHC adopted different binding posture explaining weak activity. ph17050637
The (9S)-epimer retains measurable binding affinity in some displacement-type assays but shows markedly diminished functional efficacy, suggesting a binding mode that produces less efficient receptor activation.supported
(9S)-HHC binds strongly but displays diminished activity in functional assays. acschembio.3c00254
In a β-arrestin2 CB1 recruitment bioassay, both HHC and its propyl homolog HHCP demonstrated higher CB1 activation potential than Δ⁹-THC, assessed by either higher Emax or lower EC₅₀supported
Panel of 30 THC isomers/homologs/analogs assessed via CB1 beta-arrestin2 recruitment bioassay. HHC and HHCP identified as having higher CB1 activation potential than delta9-THC based on efficacy or potency. s00204-024-03769-4
The molecular basis for the potency difference between epimers was established through molecular mechanics modelingsupported
Molecular mechanics calculations show that carbocyclic ring conformation determines orientation relative to phenyl group hydroxyl. pmid:2738895
summary5 · 5 ok
The (9R)-epimer activates CB1 with an EC₅₀ of 53.4 nM in functional agonism assays, while the (9S)-epimer is approximately 12-fold weaker (EC₅₀ = 624.3 nM)supported
9R-HHC EC50 = 53.4 nM (partial agonist); 9S-HHC EC50 = 624.3 nM (~12x less potent partial agonist). ph17050637
HHC exists as two diastereomers — the pharmacologically active (9R)-epimer and the weakly active (9S)-epimer — with the active form exhibiting potency comparable to Δ⁹-THC (EC₅₀ = 53.4 nM at CB1)supported
9R-HHC EC50 = 53.4 nM (partial agonist); 9S-HHC EC50 = 624.3 nM (~12x less potent partial agonist). delta9-THC and 9R-HHC showed comparable CB1 binding poses. ph17050637
First synthesized by Roger Adams in 1940 during foundational cannabinoid structure-activity research, HHC served as a pharmacological tool compound for over eight decades before appearing on the recreational market in approximately 2021, exploiting the hemp-derived CBD supply chain created by the 2018 US Farm Billsupported
The synthesis and cannabimimetic activity of HHC were first reported eight decades ago... Current large-scale manufacture of HHC is based on hemp-derived CBD extract. dta.3519
User-reported effects — euphoria, sedation, altered time perception, appetite enhancement — closely parallel those of Δ⁹-THC, though product variability in epimer ratios (0.2:1 to 2.4:1) introduces unpredictable potency.supported
(9R)-HHC binding affinity and activity similar to delta9-THC... wide variability in (9R):(9S) ratio (0.2:1 to 2.4:1). acschembio.3c00254
Acute oral toxicity in rats is low (estimated LD₅₀ ≈ 1000 mg/kg, OECD Category 4)supported
OECD 423 toxicity test classified HHC as Category 4, estimated LD50 1000 mg/kg. pyaf041
neuroscience3 · 3 ok
Amygdala modulation: CB1 agonism produces bidirectional effects on amygdala activity — anxiolytic at lower levels of receptor activation, anxiogenic at higher levels. This is consistent with the dose-dependent anxiety observed in rats administered HHC at 10 mg/kg and with user reports of both relaxation and paranoia.supported
10 mg/kg reduced movement, increased anxiety, impaired sensory processing. pyaf041
Basal ganglia and cerebellar effects: Dense CB1 expression in the striatum and cerebellum accounts for the motor control impairment documented in human psychophysical testing.supported
Overall, the pharmacokinetics and effects of HHC were comparable to THC. Route of administration and inter-individual factors were crucial. s41598-025-93931-4
Basal ganglia and cerebellar effects: Dense CB1 expression in the striatum and cerebellum accounts for the motor control impairment documented in human psychophysical testing.supported
Cannabimimetic effects: vertigo, headache, dizziness, dry mouth. j.forsciint.2025.112437
botanical-overview2 · 2 ok
HHC occurs in trace quantities in cannabis (Cannabis sativa) pollen and seedssupported
HHC diastereoisomers naturally found in small concentrations in pollen and seeds of hemp plants. can.2022.0253
This characterization is contested by published phytochemical literature documenting HHC in cannabis plant material.supported
HHC diastereoisomers naturally found in small concentrations in pollen and seeds of hemp plants. can.2022.0253
clinical-evidence2 · 1 ok
The two published controlled human studies — Höfert and colleagues and Lucuta and colleagues — are pilot pharmacokinetic investigations with n = 3 per groupsupported
oral (25 mg HHC fruit gum) and inhalative (three puffs from HHC vape) consumption with three participants per group. s41598-025-93931-4
Claim in clinical-evidence — inconclusiveinconclusiveworking →
history2 · 1 ok
The 11β-HHC epimer (now designated (9R)-HHC) was identified early as the pharmacologically active form, while the 11α-HHC epimer ((9S)-HHC) was recognized as minimally active — a distinction rigorously confirmed through molecular mechanics modeling in 1989.supported
11-beta-HHC is active; 11-alpha-HHC is minimally active. Molecular mechanics calculations show that carbocyclic ring conformation determines orientation relative to phenyl group hydroxyl. pmid:2738895
Claim in history — inconclusiveinconclusiveworking →
effects-overview1 · 0 ok
Claim in effects-overview — inconclusiveinconclusiveworking →