Rimonabant (also known as SR141716; trade names Acomplia, Zimulti) is an anorectic antiobesity drug that was first approved in Europe in 2006 but was withdrawn worldwide in 2008 due to serious psychiatric side effects; it was never approved in the United States. Rimonabant is an inverse agonist for the cannabinoid receptor CB1 and was the first drug approved in that class.
AM-251 is an inverse agonist at the CB1 cannabinoid receptor. AM-251 is structurally very close to rimonabant; both are biarylpyrazole cannabinoid receptor antagonists. In AM-251, the p-chloro group attached to the phenyl substituent at C-5 of the pyrazole ring is replaced with a p-iodo group. The resulting compound exhibits slightly better binding affinity for the CB1 receptor (with a Ki value of 7.5 nM) than rimonabant, which has a Ki value of 11.5 nM, AM-251 is, however, about two-fold more selective for the CB1 receptor when compared to rimonabant. Like rimonabant, it is additionally a μ-opioid receptor antagonist that attenuates analgesic effects.
Cannabinoid receptor 1 (CB1), is a G protein-coupled cannabinoid receptor that in humans is encoded by the CNR1 gene. The human CB1 receptor is expressed in the peripheral nervous system and central nervous system. It is activated by: endocannabinoids, a group of retrograde neurotransmitters that include anandamide and 2-arachidonoylglycerol (2-AG); plant phytocannabinoids, such as docosatetraenoylethanolamide found in wild daga, the compound THC which is an active constituent of the psychoactive drug cannabis; and, synthetic analogs of THC. CB1 is antagonized by the phytocannabinoid tetrahydrocannabivarin (THCV).
NESS-0327 is a drug used in scientific research which acts as an extremely potent and selective antagonist of the cannabinoid receptor CB1. It is much more potent an antagonist, and more selective for the CB1 receptor over CB2, than the more commonly used ligand rimonabant, with a Ki at CB1 of 350fM (i.e. 0.00035nM) and a selectivity of over 60,000x for CB1 over CB2. Independently, two other groups have described only modest nanomolar CB1 affinity for this compound (125nM and 18.4nM). Also unlike rimonabant, NESS-0327 does not appear to act as an inverse agonist at higher doses, instead being a purely neutral antagonist which blocks the CB1 receptor but does not produce any physiological effect of its own.
Surinabant (SR147778) is a cannabinoid receptor type 1 antagonist developed by Sanofi-Aventis. It is being investigated as a potential treatment for nicotine addiction, to assist smoking cessation. It may also be developed as an anorectic drug to assist with weight loss, however there are already several CB1 antagonists or inverse agonists on the market or under development for this application, so surinabant is at present mainly being developed as an anti-smoking drug, with possible application in the treatment of other addictive disorders such as alcoholism. Other potential applications such as treatment of ADHD have also been proposed.
VCHSR is a drug used in scientific research which acts as a selective antagonist of the cannabinoid receptor CB1. It is derived from the widely used CB1 antagonist rimonabant, and has similar potency and selectivity for the CB1 receptor, but has been modified to remove the hydrogen bonding capability in the C-3 substituent region, which removes the inverse agonist effect that rimonabant produces at high doses, so that VCHSR instead acts as a neutral antagonist, blocking the receptor but producing no physiological effect of its own.
A cannabinoid receptor antagonist, also known simply as a cannabinoid antagonist or as an anticannabinoid, is a type of cannabinoidergic drug that binds to cannabinoid receptors (CBR) and prevents their activation by endocannabinoids. They include antagonists, inverse agonists, and antibodies of CBRs. The discovery of the endocannabinoid system led to the development of CB1 receptor antagonists. The first CBR inverse agonist, rimonabant, was described in 1994. Rimonabant blocks the CB1 receptor selectively and has been shown to decrease food intake and regulate body-weight gain. The prevalence of obesity worldwide is increasing dramatically and has a great impact on public health. The lack of efficient and well-tolerated drugs to cure obesity has led to an increased interest in research and development of CBR antagonists. Cannabidiol (CBD), a naturally occurring cannabinoid, is a non-competitive CB1/CB2 receptor antagonist. And Δ9-tetrahydrocannabivarin (THCV), a naturally occurring cannabinoid, modulate the effects of THC via direct blockade of cannabinoid CB1 receptors, thus behaving like first-generation CB1 receptor inverse agonists, such as rimonabant. CBD is a very low-affinity CB1 ligand, that can nevertheless affect CB1 receptor activity in vivo in an indirect manner, while THCV is a high-affinity CB1 receptor ligand and potent antagonist in vitro and yet only occasionally produces effects in vivo resulting from CB1 receptor antagonism. THCV has also high affinity for CB2 receptors and signals as a partial agonist, differing from both CBD and rimonabant.
Ibipinabant (SLV319, BMS-646,256) is a drug used in scientific research which acts as a potent and highly selective CB1 antagonist. It has potent anorectic effects in animals, and was researched for the treatment of obesity, although CB1 antagonists as a class have now fallen out of favour as potential anorectics following the problems seen with rimonabant, and so ibipinabant is now only used for laboratory research, especially structure-activity relationship studies into novel CB1 antagonists. SLV330, which is a structural analogue of Ibipinabant, was reported active in animal models related to the regulation of memory, cognition, as well as in addictive behavior. An atom-efficient synthesis of ibipinabant has been reported.
JWH-019 is an analgesic chemical from the naphthoylindole family that acts as a cannabinoid agonist at both the CB1 and CB2 receptors. It is the N-hexyl homolog of the more common synthetic cannabinoid compound JWH-018. Unlike the butyl homolog JWH-073, which is several times weaker than JWH-018, the hexyl homolog is only slightly less potent, although extending the chain one carbon longer to the heptyl homolog JWH-020 results in dramatic loss of activity. These results show that the optimum side chain length for CB1 binding in the naphthoylindole series is the five-carbon pentyl chain, shorter than in the classical cannabinoids where a seven-carbon heptyl chain produces the most potent compounds. This difference is thought to reflect a slightly different binding conformation adopted by the naphthoylindole compounds as compared to the classical cannabinoids, and may be useful in characterizing the active site of the CB1 and CB2 receptors.
GW-842,166X is a drug which acts as a potent and selective cannabinoid CB2 receptor agonist, with a novel chemical structure based on a pyrimidine core. It has potent analgesic, anti-inflammatory and anti-hyperalgesic actions in animal models, but without cannabis-like behavioural effects due to its extremely low affinity for the CB1 receptor. GSK brought this compound for into 4 clinical trials, two of them related to pain management and the other two related to bio-distributions. The trials were either withdrawn or completed without posting result.
TM-38837 is a small molecule inverse agonist/antagonist of the CB1 cannabinoid receptor, with peripheral selectivity. It is being developed for the treatment of obesity and metabolic disorders by 7TM Pharma. The company has announced phase I clinical trials.
SR144528 is a drug that acts as a potent and highly selective CB2 receptor inverse agonist, with a Ki of 0.6 nM at CB2 and 400 nM at the related CB1 receptor. It is used in scientific research for investigating the function of the CB2 receptor, as well as for studying the effects of CB1 receptors in isolation, as few CB1 agonists that do not also show significant activity as CB2 agonists are available. It has also been found to be an inhibitor of sterol O-acyltransferase, an effect that appears to be independent from its action on CB2 receptors.
MN-25 (UR-12) is a drug invented by Bristol-Myers Squibb, that acts as a reasonably selective agonist of peripheral cannabinoid receptors. It has moderate affinity for CB2 receptors with a Ki of 11 nM, but 22x lower affinity for the psychoactive CB1 receptors with a Ki of 245 nM. The indole 2-methyl derivative has the ratio of affinities reversed however, with a Ki of 8 nM at CB1 and 29 nM at CB2, which contrasts with the usual trend of 2-methyl derivatives having increased selectivity for CB2 (cf. JWH-018 vs JWH-007, JWH-081 vs JWH-098).
Rosonabant (INN; E-6776) is a drug acting as a CB1 receptor antagonist/inverse agonist that was under investigation by Esteve as an appetite suppressant for the treatment of obesity. Development of the drug for clinical use was apparently halted shortly after the related CB1 antagonist rimonabant was discontinued in November 2008, due to the reports of severe psychiatric adverse effects such as anxiety, depression, and suicidal ideation associated with it and with similarly acting agents.
Drinabant (INN; AVE-1625) is a drug that acts as a selective CB1 receptor antagonist, which was under investigation varyingly by Sanofi-Aventis as a treatment for obesity, schizophrenia, Alzheimer's disease, Parkinson's disease, and nicotine dependence. Though initially studied as a potential treatment for a variety of different medical conditions, Sanofi-Aventis eventually narrowed down the therapeutic indications of the compound to just appetite suppression. Drinabant reached phase IIb clinical trials for this purpose in the treatment of obesity but was shortly thereafter discontinued, likely due to the observation of severe psychiatric side effects including anxiety, depression, and thoughts of suicide in patients treated with the now-withdrawn rimonabant, another CB1 antagonist that was also under development by Sanofi-Aventis.
THJ-2201 is an indazole-based synthetic cannabinoid that presumably acts as a potent agonist of the CB1 receptor and has been sold online as a designer drug.
AB-CHFUPYCA is a compound that was first identified as a component of synthetic cannabis products in Japan in 2015. The name "AB-CHFUPYCA" is an acronym of its systematic name N-(1-Amino-3-methyl-1-oxoButan-2-yl)-1-(CycloHexylmethyl)-3-(4-FlUorophenyl)-1H-PYrazole-5-CarboxAmide. There are two known regioisomers of AB-CHFUPYCA: 3,5-AB-CHMFUPPYCA (pictured) and 5,3-AB-CHMFUPPYCA. The article[1] refers to both 3,5-AB-CHMFUPPYCA and 5,3-AB-CHMFUPPYCA as AB-CHMFUPPYCA isomers, so AB-CHMFUPPYCA and AB-CHFUPYCA are not names for a unique chemical structure.
NNE1 (also known as NNEI, MN-24 and AM-6527) is an indole-based synthetic cannabinoid, representing a molecular hybrid of APICA and JWH-018 that is an agonist for the cannabinoid receptors, with Ki values of 60.09 nM at CB1 and 45.298 nM at CB2 and EC50 values of 9.481 nM at CB1 and 1.008 nM at CB2. It was invented by Abbott and has a CB1 receptor pEC50 of 8.9 with around 80x selectivity over the related CB2 receptor. It is suspected that metabolic hydrolysis of the amide group of NNE1 may release 1-naphthylamine, a known carcinogen, given the known metabolic liberation (and presence as an impurity) of amantadine in the related compound APINACA, and NNE1 was banned in New Zealand in 2012 as a temporary class drug to stop it being used as an ingredient in then-legal synthetic cannabis products. NNE1 was subsequently found to be responsible for the death of a man in Japan in 2014.
5F-AB-FUPPYCA (also known as AZ-037) is a pyrazole-based synthetic cannabinoid that is presumed to be an agonist of the CB1 receptor and has been sold online as a designer drug. It was first detected by the EMCDDA as part of a seizure of 540 g white powder in France in February 2015.
QMPSB is an arylsulfonamide-based synthetic cannabinoid that has been sold as a designer drug.
(what is this?) 
