HU-210 is a

synthetic cannabinoid Synthetic cannabinoids are a class of designer drug molecules that bind to the same receptors to which cannabinoids (THC, CBD and many others) in cannabis plants attach. These novel psychoactive substances should not be confused with synthetic ...

that was first synthesized in 1988 from (1R,5S)-myrtenol by a group led by

Raphael Mechoulam Raphael Mechoulam ( he, רפאל משולם, bg, Рафаел Мешулам; born 5 November 1930) is an Israeli organic chemist and professor of Medicinal Chemistry at the Hebrew University of Jerusalem in Israel. Mechoulam is best known for h ...

at the

Hebrew University The Hebrew University of Jerusalem (HUJI; he, הַאוּנִיבֶרְסִיטָה הַעִבְרִית בִּירוּשָׁלַיִם) is a public research university based in Jerusalem, Israel. Co-founded by Albert Einstein and Dr. Chaim Weiz ...

. HU-210 is 100 to 800 times more potent than natural

THC Tetrahydrocannabinol (THC) 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'' ...

from

cannabis ''Cannabis'' () is a genus of flowering plants in the family Cannabaceae. The number of species within the genus is disputed. Three species may be recognized: ''Cannabis sativa'', '' C. indica'', and '' C. ruderalis''. Alternatively ...

and has an extended duration of action. HU-210 has a binding affinity of 0.061nM at CB1 and 0.52nM at CB2 in cloned human cannabinoid receptors. Compared to Delta-9-THC of 40.7nM at CB1. HU-210 is the (–)-1,1-dimethylheptyl analog of 11-hydroxy- Δ⁸- tetrahydrocannabinol; in some references it is called 1,1-dimethylheptyl- 11-hydroxytetrahydrocannabinol. The abbreviation "HU" stands for Hebrew University.

Effects and research

HU-210, the (–)

enantiomer In chemistry, an enantiomer ( /ɪˈnænti.əmər, ɛ-, -oʊ-/ ''ih-NAN-tee-ə-mər''; from Ancient Greek ἐνάντιος ''(enántios)'' 'opposite', and μέρος ''(méros)'' 'part') – also called optical isomer, antipode, or optical ant ...

of 11-OH-D⁸-THC-DMH, has almost all of the cannabinoid activity, while the (+) enantiomer, known as

HU-211 Dexanabinol (HU-211 or ETS2101) is a synthetic cannabinoid derivative in development by e-Therapeutics plc. It is the "unnatural" enantiomer of the potent cannabinoid agonist HU-210. Unlike other cannabinoid derivatives, HU-211 does not act as a ...

, is inactive as a

cannabinoid Cannabinoids () are several structural classes of compounds found in the cannabis plant primarily and most animal organisms (although insects lack such receptors) or as synthetic compounds. The most notable cannabinoid is the phytocannabinoid tet ...

and instead acts as an

NMDA antagonist NMDA receptor antagonists are a class of drugs that work to antagonize, or inhibit the action of, the ''N''-Methyl-D-aspartate receptor (NMDAR). They are commonly used as anesthetics for animals and humans; the state of anesthesia they induce ...

having

neuroprotective Neuroprotection refers to the relative preservation of neuronal structure and/or function. In the case of an ongoing insult (a neurodegenerative insult) the relative preservation of neuronal integrity implies a reduction in the rate of neuronal los ...

effects. HU-210 promotes proliferation, but not differentiation, of cultured embryonic

hippocampal The hippocampus (via Latin from Greek , 'seahorse') is a major component of the brain of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. The hippocampus is part of the limbic system, an ...

neural stem and

progenitor cell A progenitor cell is a Cell (biology), biological cell that can Cellular differentiation, differentiate into a specific cell type. Stem cells and progenitor cells have this ability in common. However, stem cells are less specified than progenitor ...

s likely via a sequential activation of CB₁ receptors, G_i/o proteins, and ERK signaling. It was also indicated by this increased

neural In Biology, biology, the nervous system is the Complex system, highly complex part of an animal that coordinates its Behavior, actions and Sense, sensory information by transmitting action potential, signals to and from different parts of its ...

growth to entail

antianxiety An anxiolytic (; also antipanic or antianxiety agent) is a medication or other intervention that reduces anxiety (mood), anxiety. This effect is in contrast to anxiogenic agents which increase anxiety. Anxiolytic medications are used for the tre ...

and

antidepressant Antidepressants are a class of medication used to treat major depressive disorder, anxiety disorders, chronic pain conditions, and to help manage addictions. Common side-effects of antidepressants include dry mouth, weight gain, dizziness, hea ...

effects. HU-210, alongside other synthetic cannabinoids like

WIN 55,212-2 WIN 55,212-2 is a chemical described as an aminoalkylindole derivative, which produces effects similar to those of cannabinoids such as tetrahydrocannabinol (THC) but has an entirely different chemical structure. WIN 55,212-2 is a potent cannab ...

and

JWH-133 JWH-133 (Dimethylbutyl-deoxy-Delta-8-THC) is a potent selective CB2 receptor agonist with a Ki of 3.4nM and selectivity of around 200x for CB2 over CB1 receptors. It was discovered by and named after, John W. Huffman. It's important to note t ...

, is implicated in preventing the inflammation caused by

amyloid beta Amyloid beta (Aβ or Abeta) denotes peptides of 36–43 amino acids that are the main component of the amyloid plaques found in the brains of people with Alzheimer's disease. The peptides derive from the amyloid precursor protein (APP), which is ...

proteins involved in

Alzheimer's disease Alzheimer's disease (AD) is a neurodegeneration, neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in short-term me ...

, in addition to preventing cognitive impairment and loss of neuronal markers. This anti-inflammatory action is induced through the activation of

cannabinoid receptor Cannabinoid receptors, located throughout the body, are part of the endocannabinoid system a class of cell membrane receptors in the G protein-coupled receptor superfamily. As is typical of G protein-coupled receptors, the cannabinoid recepto ...

s, which prevents

microglia Microglia are a type of neuroglia (glial cell) located throughout the brain and spinal cord. Microglia account for about 7% of cells found within the brain. As the resident macrophage cells, they act as the first and main form of active immune de ...

l activation that elicits the inflammation. In addition, cannabinoids completely abolish neurotoxicity related to microglia activation in rat models. HU-210 is a potent

analgesic An analgesic drug, also called simply an analgesic (American English), analgaesic (British English), pain reliever, or painkiller, is any member of the group of drugs used to achieve relief from pain (that is, analgesia or pain management). It ...

with many of the same effects as natural THC. HU-210 has an oral LD50 of 5,000mg/kg in rats and 14,200mg/kg in rabbits. HU-210 has an LDLO (Lowest Lethal Dose amount) of 143mg/kg in humans. Caffeine has an LD50 estimated to be 150–200 milligrams per kilogram. Delta-8-THC LD50 has not been confirmed. In a 1973 study monkeys and dogs given 9,000mg/kg of Delta-8-THC was nonlethal.

Chemistry

HU-210 is the

(

Dexanabinol Dexanabinol (HU-211 or ETS2101) is a synthetic cannabinoid derivative in development by e-Therapeutics plc. It is the "unnatural" enantiomer of the potent cannabinoid agonist HU-210. Unlike other cannabinoid derivatives, HU-211 does not act as a ...

). The original synthesis of HU-210 is based on an acid-catalyzed condensation of (–)-

Myrtenol Myrtenol is a chemical compound isolated from plants in the genus ''Taxus''. See also * Myrtenal Myrtenal is a bicyclic monoterpenoid with the chemical formula C10H14O. It is a naturally occurring molecule that can be found in numerous plant ...

and 1,1-Dimethylheptylresorcinol (3,5-Dihydroxy-1-(1,1-dimethylheptyl)benzol). HU-210 synthesis

Legal status

HU-210 is not listed in the schedules set out by the

United Nations The United Nations (UN) is an intergovernmental organization whose stated purposes are to maintain international peace and international security, security, develop friendly relations among nations, achieve international cooperation, and be ...

Single Convention on Narcotic Drugs The Single Convention on Narcotic Drugs, 1961 (Single Convention, 1961 Convention, or C61) is an international treaty that controls activities (cultivation, production, supply, trade, transport) of specific narcotic drugs and lays down a syst ...

from 1961 nor their

Convention on Psychotropic Substances The Convention on Psychotropic Substances of 1971 is a United Nations treaty designed to control psychoactive drugs such as #Amphetamine-type stimulants, amphetamine-type stimulants, barbiturates, benzodiazepines, and Psychedelic drug, psychede ...

from 1971, so the signatory countries to these international drug control treaties are not required by said treaties to control HU-210.

New Zealand

HU-210 is banned in New Zealand as of 8 May 2014.

United States

HU-210 is not listed in the list of scheduled controlled substances in the USA. It is therefore not

scheduled A schedule or a timetable, as a basic time-management tool, consists of a list of times at which possible tasks, events, or actions are intended to take place, or of a sequence of events in the chronological order in which such things are i ...

at the

federal level Federal or foederal (archaic) may refer to: Politics General *Federal monarchy, a federation of monarchies *Federation, or ''Federal state'' (federal system), a type of government characterized by both a central (federal) government and states or ...

in the United States, but it is possible that HU-210 could legally be considered an

analog Analog or analogue may refer to: Computing and electronics * Analog signal, in which information is encoded in a continuous variable ** Analog device, an apparatus that operates on analog signals *** Analog electronics, circuits which use analog ...

of Delta-9-THC (which is one of the substances controlled in Schedule I as "tetrahydrocannabinols"), and therefore sales or

possession Possession may refer to: Law * Dependent territory, an area of land over which another country exercises sovereignty, but which does not have the full right of participation in that country's governance * Drug possession, a crime * Ownership * ...

could potentially be prosecuted under the

Federal Analogue Act The Federal Analogue Act, , is a section of the United States Controlled Substances Act passed in 1986 which allows any chemical "substantially similar" to a controlled substance listed in Schedule I or II to be treated as if it were listed in ...

. A brief profile of HU-210 written and published by the

Drug Enforcement Administration The Drug Enforcement Administration (DEA; ) is a Federal law enforcement in the United States, United States federal law enforcement agency under the U.S. Department of Justice tasked with combating drug trafficking and distribution within th ...

(DEA) in 2009 (but subsequently removed from the DEA's website several years later) stated that HU-210 is a Schedule I controlled substance under the

Controlled Substances Act The Controlled Substances Act (CSA) is the statute establishing federal government of the United States, federal drug policy of the United States, U.S. drug policy under which the manufacture, importation, possession, use, and distribution of ...

due to being similar to

. This indicates that the DEA might legally consider HU-210 to be an analogue of Delta-8-THC for the purposes of applying the Federal Analog Act to those that handle HU-210. An elucidation of the rationale for the DEA's claim was not presented, no references were cited, and the claim was eventually removed from the DEA's website. A version of the document (updated in 2013), now in PDF form, exists on the DEA Office of Diversion Control's website. Claimed in this possibly misleading though definitive sounding document, with the same lack of detailed explanation or citation, is:

Alabama

HU-210 is a Schedule I controlled substance in

Alabama (We dare defend our rights) , anthem = "Alabama (state song), Alabama" , image_map = Alabama in United States.svg , seat = Montgomery, Alabama, Montgomery , LargestCity = Huntsville, Alabama, Huntsville , LargestCounty = Baldwin County, Al ...

Florida

HU-210 is a Schedule I

controlled substance A controlled substance is generally a drug or chemical whose manufacture, possession and use is regulated by a government, such as illicitly used drugs or prescription medications that are designated by law. Some treaties, notably the Single C ...

, categorized as a

hallucinogen Hallucinogens are a large, diverse class of psychoactive drugs that can produce altered states of consciousness characterized by major alterations in thought, mood, and perception as well as other changes. Most hallucinogens can be categorized ...

, making it illegal to buy, sell, or possess in the state of

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

without a license.

Vermont

Effective January 1, 2016, HU-210 is a regulated drug in Vermont designated as a "Hallucinogenic Drug."

Other HU Cannabinoids

* HU-239 *

HU-243 HU-243 (AM-4056) is a synthetic cannabinoid drug that is a single enantiomer of the hydrogenated derivative of the commonly used reference agonist HU-210. It is a methylene homologue of canbisol. It is a potent agonist at both the CB1 and ...

HU-308 HU-308 (also known as onternabez, HU308, PPP-003 and ARDS-003) is a cannabidiol (CBD)-derivative drug that acts as a potent cannabinoid agonist. It is highly selective for the cannabinoid-2 receptor (CB2 receptor) subtype, with a selectivity ...

HU-320 HU-320 (7-nor-7-carboxy-CBD-1,1-DMH) is a drug related to cannabidiol, which has strong antiinflammatory and immunosuppressive properties while demonstrating no psychoactive effects. See also * 7-Hydroxycannabidiol * Ajulemic acid * HU-210 * HU- ...

HU-331 HU-331 is a quinone anticarcinogenic drug synthesized from cannabidiol, a cannabinoid in the ''Cannabis sativa'' plant. It showed a great efficacy against oncogenic human cells. HU-331 does not cause arrest in cell cycle, cell apoptosis or caspas ...

HU-336 HU-336 is a strongly antiangiogenic compound, significantly inhibiting angiogenesis at concentrations as low as 300 nM. It inhibits angiogenesis by directly inducing apoptosis of vascular endothelial cells without changing the expression of ...

HU-345 HU-345 (cannabinol quinone) is a drug that is able to inhibit aortic ring angiogenesis more potently than its parent compound cannabinol (CBN). It exhibits no psychoactive effects on the body. HU-345 can be derived through the oxidative degr ...