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Names | |
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IUPAC name 6,6,9-trimethyl-3-pentyl-6a,7,10,10a-tetrahydrobenzo[c]chromen-1-ol | |
Other names
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Identifiers | |
3D model (JSmol) | |
ChEMBL | |
ChemSpider | |
ECHA InfoCard | 100.165.076 |
KEGG | |
PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
C21H30O2 | |
Molar mass | 314.5 g/mol |
Density | 1.0±0.1 g/cm3 |
Boiling point | 383.5±42.0 °C |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Δ-8-tetrahydrocannabinol (delta-8-THC, [lower-alpha 1] Δ8-THC) is a psychoactive cannabinoid found in the Cannabis plant. [1] [2] [3] It is an isomer of delta-9-tetrahydrocannabinol (delta-9-THC, Δ9-THC), the compound commonly known as THC, with which it co-occurs in hemp; natural quantities of ∆8-THC found in hemp are low. [4]
Psychoactive effects are similar to that of Δ9-THC, with central effects occurring by binding to cannabinoid receptors found in various regions of the brain. During the production process of converting cannabidiol extracted from hemp to ∆8-THC, toxic chemical reagents are used, which can contaminate the product. In the US, ∆8-THC products are neither mandatorily tested nor FDA approved, hence concern has been raised about their safety. In addition, as of 2022, the safety profile of regular, long-term delta-8-THC consumption is unknown.
Partial synthesis of ∆8-THC was published in 1941 by Roger Adams and colleagues at the University of Illinois. After the 2018 United States farm bill was signed, ∆8-THC products partially synthesized from compliant sources (including industrial hemp and derivative cannabidiol extracts) experienced a rise in popularity; THC products have been sold in licensed, regulated recreational cannabis and medical cannabis industries within the United States only in California, Pennsylvania, and regulated in Michigan and Oregon. According to a March 2024 study, [5] 11% of US twelfth graders have used ∆8-THC over the past 12 months.
∆8-THC is moderately less potent than Δ9-THC. [6] [7] This means that while its effects are similar to that of Δ9-THC, it would take more ∆8-THC to achieve a comparable level of effect. [8]
A 1973 study testing the effects of ∆8-THC in dogs and monkeys reported that a single oral dose of 9,000 milligrams per kilogram of body mass (mg/kg) was nonlethal in all dogs and monkeys studied. [9] [10] The same study reported that the median lethal dose of ∆8-THC in rats was comparable to that of ∆9-THC. [9] Both isomers of THC have been found to cause a transient increase in blood pressure in rats, [11] although the effects of cannabinoids on the cardiovascular system are complex. [12] Animal studies indicate that ∆8-THC exerts many of its central effects by binding to cannabinoid receptors found in various regions of the brain, including the cerebral cortex, thalamus, basal ganglia, hippocampus, and cerebellum. [13] [14]
∆8-THC is typically synthesized from cannabidiol extracted from hemp, [15] as the natural quantities of ∆8-THC found in hemp are low. This is called semisynthesis or partial synthesis. The reaction often yields a mixture that contains other cannabinoids and unknown reaction by-products. As a result, most products sold as ∆8-THC are not actually pure ∆8-THC. [15] Little is known about the identity and the health effects of the impurities. [15] Some manufacturers of ∆8-THC may use household chemicals in the synthesis process, potentially introducing harmful contaminants. [16] In that sense, ∆8-THC can be called a "semisynthetic phytocannabinoid" or semisynthetic endocannabinoid, as it is obtained by (partial) chemical synthesis. It is not to be confused with the term synthetic cannabinoid, however.
As of 2022, the safety profile, including risks of psychosis and addiction after regular, long-term delta-8-THC use was unknown. [17]
As of 2022, there have been at least 104 adverse event reports made regarding ∆8-THC, [16] and at least two deaths associated with ∆8-THC products. [18] [19] US national poison control centers received 2,362 exposure cases of delta-8 THC products between January 1, 2021, and February 28, 2022; 58% of these exposures involved adults, and 70% thought they required medical care. [16]
The pharmacodynamic profile of ∆8-THC is similar to that of ∆9-THC. [6] [7] It is a partial agonist of CB1 and CB2 cannabinoid receptors with about half the potency of ∆9-THC in most but not all measures of biological activity. [20] [21] [22] ∆8-THC has been reported to have a Ki value of 44 ± 12 nM at the CB1 receptor and 44 ± 17 nM at the CB2 receptor. [23] These values are higher than those typically reported for ∆9-THC (CB1 Ki = 40.7 nM) at the same receptors, indicating that ∆8-THC binds to cannabinoid receptors less efficiently than ∆9-THC. [24]
The pharmacokinetic profile of ∆8-THC is also similar to that of ∆9-THC. [6] [7] Following ingestion in humans, hepatic cytochrome P450 enzymes including CYP2C9 and CYP3A4 first convert ∆8-THC into 11-hydroxy-Δ8-tetrahydrocannabinol (11-OH-Δ8-THC). [25] [26] Next, dehydrogenase enzymes convert 11-OH-Δ8-THC into 11-nor-Δ8-tetrahydrocannabinol-9-carboxylic acid (11-nor-Δ8-THC-9-COOH, also known as Δ8-THC-11-oic acid). [26] [27] Finally, Δ8-THC-11-oic acid undergoes glucuronidation by glucuronidase enzymes to form 11-nor-Δ8-tetrahydrocannabinol-9-carboxylic acid glucuronide (Δ8-THC-COOH-glu), [26] [27] which is then excreted in the urine. [28] [29]
∆8-THC is a tricyclic terpenoid. Although it has the same chemical formula as ∆9-THC, one of its carbon-carbon double bonds is located in a different position. [6] In ∆8-THC, the double bond is between the eighth and ninth carbons in structure, while in Δ9-THC, the double bond is between the ninth and tenth carbons in structure.
This difference in structure increases the chemical stability of ∆8-THC relative to ∆9-THC, lengthening shelf life and allowing the compound to resist undergoing oxidation to cannabinol over time. [20] Like other cannabinoids, ∆8-THC is very lipophilic (log P = 7.4 [30] ). It is an extremely viscous, colorless oil at room temperature. [31]
While ∆8-THC is naturally found in plants of the Cannabis genus, [3] this compound can also be produced in an industrial or laboratory setting by exposing CBD to acids and heat. [32] [33] [34] Solvents that may be used during this process include methylene chloride, toluene, and hexane. [34] Various Brønsted or Lewis acids that may be used to facilitate this isomerization include tosylic acid, indium(III) triflate, trimethylsilyl trifluoromethanesulfonate, hydrochloric acid, and sulfuric acid. [34] [35] Because it is possible for chemical contaminants to be generated during the process of converting CBD to ∆8-THC, such as Δ10-THC, 9-OH-HHC and other side products, as well as the potentially toxic chemical reagents used during manufacture, concern has been raised about the safety of untested or impure ∆8-THC products. [35] [36]
The ongoing controversy regarding the legal status of ∆8-THC in the U.S. () is complicated by chemical nomenclature. According to a 2019 literature review published in Clinical Toxicology , the term synthetic cannabinoid typically refers to a full agonist of CB1 and CB2 cannabinoid receptors. [37] According to the review, the following is stated:
"The psychoactive (and probably the toxic) effects of synthetic cannabinoid receptor agonists are likely due to their action as full receptor agonists and their greater potency at CB1 receptors."
However, ∆8-THC and ∆9-THC are partial agonists of cannabinoid receptors. [21] They are less potent and less toxic than many synthetic cannabinoids. [38] It has not been definitively proven if full agonism is the reason for toxicity since ∆9-THC has been shown to act as a full CB1 agonist on specific CB1 receptors located in the hippocampus section of the brain. [39] Furthermore, the synthetic cannabinoid EG-018 acts as a partial agonist. [40] The classical cannabinoid structure is that of a dibenzopyran structure. This group includes THC. THC interacts with a different spot inside of the CB1 receptor than synthetic cannabinoid such JWH-018. This may explain the latter's toxicity. [41]
The partial synthesis of ∆8-THC was published in 1941 by Roger Adams and colleagues at the University of Illinois. [42] In 1942, the same research group studied its physiological and psychoactive effects after oral dosing in human volunteers. [43] Total syntheses of ∆8-THC were achieved by 1965. [44] In 1966, the chemical structure of ∆8-THC isolated from cannabis was characterized using modern methods by Richard L. Hively, William A. Mosher, and Friedrich W. Hoffmann at the University of Delaware. [45] A stereospecific synthesis of ∆8-THC from olivetol and verbenol was reported by Raphael Mechoulam and colleagues at the Weizmann Institute of Science in 1967. [46] ∆8-THC was often referred to as "Delta-6-THC" (Δ6-THC) in early scientific literature, but this name is no longer conventional among most authors. [47]
In 1937, ∆9-THC was effectively made illegal with the passage of the (since-repealed) Marihuana Tax Act, which made growing cannabis require a tax stamp. President Ronald Reagan re-enacted mandatory sentences [48] [49] for cannabis-related offenses. [50] As of 1 September 2023, 24 states have legalized cannabis, with others having reduced penalties.
The 2018 United States farm bill, signed into law in December 2018, states the following:
"The term hemp means the plant Cannabis sativa L. and any part of that plant, including the seeds thereof and all derivatives, extracts, cannabinoids, isomers, acids, salts, and salts of isomers, whether growing or not, with a delta-9 tetrahydrocannabinol concentration of not more than 0.3 percent on a dry weight basis."
Despite claims of legality by manufacturers, independent testing of products from retail has often revealed significant levels of ∆9-THC. Many of these levels are well above one legal threshold. [51] [52] [53]
In October 2020, the DEA Interim Final Rule [54] addressed synthetic cannabinoids. Some believed that this also applied to ∆8-THC products and other hemp derivatives allowed by the Farm Bill. [55] [56]
∆8-THC has not been evaluated or approved by the FDA. Consequently, Δ-8-tetrahydrocannabinol is not recognized under the Federal Food, Drug, and Cosmetic Act as safe and effective for any use. [57] The FDA has taken action against businesses that have illegally marketed ∆8-THC for therapeutic use. [58] The FDA has also taken action against businesses that sold ∆8-THC in forms that closely resemble (typically non-psychoactive) food products such as chips or cookies. [59]
While most states have not arrested significant numbers of people for ∆8-THC, a handful have been arrested and charged, leading to confusion as to its legal status in those states. [60] [61] [62] [63]
In 2021, one store owner in Menomonee Falls, Wisconsin was facing a sentence of up to 50 years for allegedly selling ∆8-THC products with illegal amounts of ∆9-THC. [64] [65] Other raids and arrests have happened due to the ∆9-THC content of these products in North Carolina, and Texas, among other places. [66] [67] [68] In 2024, the Texas Court of Criminal Appeals is considering the first criminal case involving a felony conviction for ∆8 possession (a writ of habeas corpus originating from Brazos County) - to make the highest state criminal court, Ex Parte John Ward. [69] In 2022, Catoosa County, Georgia Sheriff Sisk announced to prosecute stores distributing ∆8-THC with non-compliant ∆9-THC levels: "The products the sheriffs office has purchased and tested all contain significant levels of ∆9. [We have the] evidence needed to move forward with prosecution and seizures." [70] There are also issues related to incidental manufacture of ∆9 THC, as ∆9 is produced as an intermediate product in the process of acid catalyzed ring closure of cannabidiol. [71]
There are multiple court decisions pertaining to the legality of Delta-8 THC. AK Futures LLC vs Boyd Street Distro, LLC (2022) was one of the earliest decisions made in a federal court, stating "On the available record, the delta-8 THC in AK Futures’ e-cigarette liquid appears to fit comfortably within the statutory definition of “hemp.”". [72] United States vs. Rice, however, came to the opposite conclusion, "In short, Delta-8 remains a controlled substance. Although Delta-10 was not directly referenced in the DEA’s letter, there is no basis (in the record before the court) to believe that the DEA will treat Delta-10 in a different manner.". United States vs. Plancarte also states, "There is no legal D9-THC threshold for synthetic derivatives of THC. A gray area is whether Delta-8 THC is legal; it probably is when it occurs naturally in hemp, but this is not clear." [73]
∆8-THC products have been sold in licensed, regulated recreational cannabis and medical cannabis industries within the United States including California [74] and Pennsylvania's licensed, regulated medical cannabis system since 2020. [75] [76] [77] [78] Both Michigan [79] and the state of Oregon have regulated Delta-8-THC products sold under their regulated cannabis system. [80]
Common Delta-8 products range from bulk quantities of unrefined distillate to prepared cannabis edibles and atomizer cartridges. [81] [82] In the US, they are usually marketed as federally legal alternatives to their ∆9-THC counterparts. [83]
∆8-THC products partially synthesized from compliant sources (including industrial hemp and derivative cannabidiol extracts) experienced a rise in popularity in the US following the passage of the 2018 Farm Bill. [84] This led to it being sold by a diverse range of retailers, including head shops, smoke shops, vape shops, dispensaries, gas stations, and convenience stores. [85] [86]
In March 2024, a study of self-reported prevalence of Δ8-THC use among US twelfth graders was published: Of those reporting Δ8-THC use, 35% had used it at least 10 times in the past 12 months. Consumption was lower in Western than Southern and in states, where Δ8-THC was regulated versus not regulated. [87]
Although it is a minor constituent of medical cannabis, no large clinical studies have been conducted on delta-8-THC alone as of 2022. [88] One study (ongoing as of November 2023) is focused on determining the degree of pharmacologic and pharmacokinetic similarity between ∆8-THC and ∆9-THC. [89]
Tetrahydrocannabinol (THC) is a cannabinoid found in cannabis. It is the principal psychoactive constituent of cannabis and one of at least 113 total cannabinoids identified on the plant. Although the chemical formula for THC (C21H30O2) describes multiple isomers, the term THC usually refers to the delta-9-THC isomer with chemical name (−)-trans-Δ9-tetrahydrocannabinol. It is a colorless oil.
Cannabinoids are several structural classes of compounds found in the cannabis plant primarily and most animal organisms or as synthetic compounds. The most notable cannabinoid is the phytocannabinoid tetrahydrocannabinol (THC) (delta-9-THC), the primary psychoactive compound in cannabis. Cannabidiol (CBD) is also a major constituent of temperate cannabis plants and a minor constituent in tropical varieties. At least 113 distinct phytocannabinoids have been isolated from cannabis, although only four have been demonstrated to have a biogenetic origin. It was reported in 2020 that phytocannabinoids can be found in other plants such as rhododendron, licorice and liverwort, and earlier in Echinacea.
Cannabinol (CBN) is a mildly psychoactive cannabinoid (e.g., cannabidiol (CBD)) that acts as a low affinity partial agonist at both CB1 and CB2 receptors. This activity at CB1 and CB2 receptors constitutes interaction of CBN with the endocannabinoid system (ECS).
Cannabidiol (CBD) is a phytocannabinoid, one of 113 identified cannabinoids in cannabis plants, along with tetrahydrocannabinol (THC), and accounts for up to 40% of the plant's extract. It was discovered in 1940 and as of 2022, clinical research on CBD included studies related to the treatment of anxiety, addiction, psychosis, movement disorders, and pain, but there is insufficient high-quality evidence that CBD is effective for these conditions. CBD is sold as a herbal dietary supplement and promoted with yet unproven claims of particular therapeutic effects.
Tetrahydrocannabivarin is a homologue of tetrahydrocannabinol (THC) having a propyl (3-carbon) side chain instead of pentyl (5-carbon), making it non-psychoactive in lower doses. It has been shown to exhibit neuroprotective activity, appetite suppression, glycemic control and reduced side effects compared to THC, making it a potential treatment for management of obesity and diabetes. THCV was studied by Roger Adams as early as 1942.
Parahexyl is a synthetic homologue of THC which was invented in 1941 during attempts to elucidate the structure of Δ9-THC, one of the active components of cannabis.
THC-O-acetate is the acetate ester of THC. The term THC-O-acetate and its variations are commonly used for two types of the substance, dependent on which cannabinoid it is synthesized from. The difference between Δ8-THC and Δ9-THC is bond placement on the cyclohexene ring.
11-Hydroxy-Δ9-tetrahydrocannabinol, usually referred to as 11-hydroxy-THC is the main active metabolite of tetrahydrocannabinol (THC), which is formed in the body after Δ9-THC is consumed.
Cannabigerol (CBG) is a non-psychoactive cannabinoid and minor constituent of cannabis. It is one of more than 120 identified cannabinoids found in the plant genus Cannabis. The compound is the decarboxylated form of cannabigerolic acid (CBGA), the parent molecule from which other cannabinoids are biosynthesized.
Δ9-Tetrahydrocannabutol is a phytocannabinoid found in cannabis that is a homologue of tetrahydrocannabinol (THC), the main active component of Cannabis. Structurally, they are only different by the pentyl side chain being replaced by a butyl side chain. THCB was studied by Roger Adams as early as 1942
Cannabichromene (CBC), also called cannabichrome, cannanbichromene, pentylcannabichromene or cannabinochromene, exhibits anti-inflammatory properties in vitro, which may, theoretically, contribute to cannabis analgesic effects. It is a phytocannabinoid, one of the hundreds of cannabinoids found in the Cannabis plant. It bears structural similarity to the other natural cannabinoids, including tetrahydrocannabinol (THC), tetrahydrocannabivarin (THCV), cannabidiol (CBD), and cannabinol (CBN), among others. CBC and cannabinols are present in cannabis. It is not scheduled by the Convention on Psychotropic Substances.
Dronabinol, also known under the brand names Marinol and Syndros, is a generic name for the molecule of delta-9-tetrahydrocannabinol in the pharmaceutical context. It has indications as an appetite stimulant, antiemetic, and sleep apnea reliever and is approved by the FDA as safe and effective for HIV/AIDS-induced anorexia and chemotherapy-induced nausea and vomiting only.
Tetrahydrocannabinolic acid is a precursor of tetrahydrocannabinol (THC), an active component of cannabis.
8,9-Dihydrocannabidiol is a synthetic cannabinoid that is closely related to cannabidiol (CBD) itself. that was first synthesized by Alexander R. Todd in 1940 derived from the catalytic hydrogenation of cannabidiol.
Tetrahydrocannabiphorol (THCP) is a potent phytocannabinoid, a CB1 and CB2 agonist which was known as a synthetic homologue of THC, but for the first time in 2019 was isolated as a natural product in trace amounts from Cannabis sativa. It is structurally similar to Δ9-THC, the main active component of cannabis, but with the pentyl side chain extended to heptyl. Since it has a longer side chain, its cannabinoid effects are "far higher than Δ9-THC itself." Tetrahydrocannabiphorol has a reported binding affinity of 1.2 nM at CB1, approximately 33 times that of Δ9-THC (40 nM at CB1).
Hexahydrocannabinol (HHC) is a hydrogenated derivative of tetrahydrocannabinol (THC). It is a naturally occurring phytocannabinoid that has rarely been identified as a trace component in Cannabis sativa, but can also be produced synthetically by firstly acid cyclization of cannabidiol and then hydrogenation of tetrahydrocannabinol. The synthesis and bioactivity of HHC was first reported in 1940 by Roger Adams.
11-Hydroxy-Delta-8-tetrahydrocannabinol is an active metabolite of Δ8-THC, a psychoactive cannabinoid found in small amounts in cannabis. It is an isomer of 11-OH-Δ9-THC, and is produced via the same metabolic pathway. It was the first cannabinoid metabolite discovered in 1970.
Tetrahydrocannabihexol is a phytocannabinoid, the hexyl homologue of tetrahydrocannabinol (THC) which was first isolated from Cannabis plant material in 2020 along with the corresponding hexyl homologue of cannabidiol, though it had been known for several decades prior to this as an isomer of the synthetic cannabinoid parahexyl. Another isomer Δ8-THCH is also known as a synthetic cannabinoid under the code number JWH-124, though it is unclear whether this occurs naturally in Cannabis, but likely is due to Δ8-THC itself being a degraded form of Δ9-THC. THC-Hexyl can be synthesized from 4-hexylresorcinol and was studied by Roger Adams as early as 1942.
JWH-138 (THC-Octyl, Δ8-THC-C8) is a synthetic cannabinoid first synthesized by Roger Adams and studied heavily by John W. Huffman, with a Ki of 8.5nM at the CB1 cannabinoid receptor. THC-Octyl and its hydrogenated analog HHC-Octyl was synthesized and studied by Roger Adams as early as 1942.
Cannabidiol (CBD) can be chemically converted into tetrahydrocannabinol (THC) via a ring-closing reaction. This cyclization can be acid-catalyzed or brought about by heating.
Located at vape shops, convenience stores and even gas stations, Delta-8 is well-accessible to consumers. Products are available in different forms, including gummies, chocolate, vaping cartridges, infused drinks and even breakfast cereal.
We're seeing delta 8 products being sold across the state, everywhere we went to every vape shop we visited and gas stations as well,