The 5-HT2A receptor is a subtype of the 5-HT2 receptor that belongs to the serotonin receptor family and is a G protein-coupled receptor (GPCR). The 5-HT2A receptor is a cell surface receptor, but has several intracellular locations.
5-MeS-DMT (5-methylthio-N,N-dimethyltryptamine) is a lesser-known psychedelic drug. It is the 5-methylthio analog of dimethyltryptamine (DMT). 5-MeS-DMT was first synthesized by Alexander Shulgin. In his book TiHKAL, the minimum dosage is listed as 15-30 mg. The duration listed as very short, just like DMT. 5-MeS-DMT produces similar effects to DMT, but weaker. Shulgin describes his feelings while on a low dose of this drug as "pointlessly stoned", although at a higher dose of 20 mg he says it is "quite intense" and suggests that a higher dose still might have full activity.
Quipazine, also known as 1-(2-quinolinyl)piperazine, is a serotonergic drug of the arylpiperazine family and an analogue of 1-(2-pyridinyl)piperazine which is used in scientific research. It was first described in the 1960s and was originally intended as an antidepressant but was never developed or marketed for medical use.
5-Fluoro-N,N-dimethyltryptamine is a tryptamine derivative related to compounds such as 5-bromo-DMT and 5-MeO-DMT. It produces a robust head-twitch response in mice, and hence is a putative serotonergic psychedelic. Fluorination of psychedelic tryptamines either reduces or has little effect on 5-HT2A/C receptor affinity or intrinsic activity, although 6-fluoro-DET is inactive as a psychedelic despite acting as a 5-HT2A agonist, while 4-fluoro-5-methoxy-DMT is a much stronger agonist at 5-HT1A than 5-HT2A.
5-Methoxy-7,N,N-trimethyltryptamine (5-MeO-7,N,N-TMT, 5-MeO-7-TMT), is a tryptamine derivative which acts as a partial agonist at the 5-HT2 serotonin receptors, with an EC50 of 63.9 nM and an efficacy of 66.2% at 5-HT2A (vs 5-HT), and weaker activity at 5-HT2B and 5-HT2C. In animal tests, both 7,N,N-TMT and 5-MeO-7,N,N-TMT produced behavioural responses similar to those of psychedelic drugs such as DMT and 5-MeO-DMT, but compounds with larger 7-position substituents such as 7-ethyl-DMT and 7-bromo-DMT did not produce psychedelic-appropriate responding despite high 5-HT2 receptor binding affinity, suggesting these may be antagonists or weak partial agonists for the 5-HT2 receptors. The related compound 7-MeO-MiPT (cf. 5-MeO-MiPT) was also found to be inactive, suggesting that the 7-position has poor tolerance for bulky groups at this position, at least if agonist activity is desired.
7,N,N-trimethyltryptamine (7-methyl-DMT, 7-TMT), is a tryptamine derivative which acts as an agonist of 5-HT2 receptors. In animal tests, both 7-TMT and its 5-methoxy derivative 5-MeO-7-TMT produced behavioural responses similar to those of psychedelic drugs such as DMT, but the larger 7-ethyl and 7-bromo derivatives of DMT did not produce psychedelic responses despite having higher 5-HT2 receptor affinity in vitro (cf. DOBU, DOAM). 7-TMT also weakly inhibits reuptake of serotonin but with little effect on dopamine or noradrenaline reuptake.
Substituted tryptamines, or simply tryptamines, also known as serotonin analogues (i.e., 5-hydroxytryptamine analogues), are organic compounds which may be thought of as being derived from tryptamine itself. The molecular structures of all tryptamines contain an indole ring, joined to an amino (NH2) group via an ethyl (−CH2–CH2−) sidechain. In substituted tryptamines, the indole ring, sidechain, and/or amino group are modified by substituting another group for one of the hydrogen (H) atoms.
The head-twitch response (HTR), also sometimes known as wet dog shakes (WDS) in rats, is a rapid side-to-side head movement that occurs in mice and rats when the serotonin 5-HT2A receptor is activated. Serotonergic psychedelics, including lysergic acid diethylamide (LSD), induce the HTR, and so the HTR is widely used as an animal behavioral model of hallucinogen effects and to discover new psychedelic drugs. HTR-like effects are also induced by psychedelics in other animal species, for instance cats and stump-tailed macaque monkeys. Other related behaviors to head twitches induced by serotonergic agents include limb jerks and body scratches. The only other behavioral paradigms for assessment of psychedelic-like effects in animals are drug discrimination (DD), prepulse inhibition (PPI), and time perception.
25CN-NBOH is a compound indirectly derived from the phenethylamine series of hallucinogens, which was discovered in 2014 at the University of Copenhagen. It is a member of the NBOMe family of psychedelics.
5-Chloro-α-methyltryptamine (5-Chloro-αMT), also known as PAL-542, is a tryptamine derivative related to α-methyltryptamine (αMT) and one of only a few known serotonin–dopamine releasing agents (SDRAs). It is also a potent serotonin 5-HT2A receptor agonist and hence may be a serotonergic psychedelic. The drug has been investigated in animals as a potential treatment for cocaine dependence.
AAZ-A-154, also known as DLX-001 or as (R)-5-methoxy-N,N-dimethyl-α-methylisotryptamine, is a novel isotryptamine derivative which acts as a serotonin 5-HT2A receptor agonist discovered and synthesized by the lab of Professor David E. Olson at the University of California, Davis. It is being developed for the treatment of major depressive disorder and other central nervous system disorders.
O-Acetylbufotenine, or bufotenine O-acetate, also known as 5-acetoxy-N,N-dimethyltryptamine (5-AcO-DMT) or O-acetyl-N,N-dimethylserotonin, is a synthetic tryptamine derivative and putative serotonergic psychedelic. It is the O-acetylated analogue of the naturally occurring peripherally selective serotonergic tryptamine bufotenine and is thought to act as a centrally penetrant prodrug of bufotenine.
6-Fluoro-DET is a substituted tryptamine derivative related to drugs such as DET and 5-fluoro-DET. It acts as a partial agonist at the 5-HT2A receptor, but while it produces similar physiological effects to psychedelic drugs, it does not appear to produce psychedelic effects itself even at high doses. For this reason it saw some use as an active placebo in early clinical trials of psychedelic drugs but was regarded as having little use otherwise, though more recent research into compounds such as AL-34662, TBG and AAZ-A-154 has shown that these kind of non-psychedelic 5-HT2A agonists can have various useful applications.
6-MeO-DMT, or 6-methoxy-N,N-dimethyltryptamine, also known as 6-OMe-DMT, is a serotonergic drug of the tryptamine family. It is the 6-methoxy derivative of the serotonergic psychedelic N,N-dimethyltryptamine (DMT) and is a positional isomer of the serotonergic psychedelic 5-MeO-DMT.
BMB-202 is a serotonin 5-HT2A receptor agonist and psychedelic hallucinogen which is under development for the treatment of depressive disorders and post-traumatic stress disorder (PTSD). It is taken by mouth. However, BMB-202 has also been evaluated by injection in preclinical studies.
Isotryptamine, also known as 2-(1-indolyl)ethylamine, is a chemical compound and positional isomer of tryptamine.
5-MeO-isoDMT, or 5-OMe-isoDMT, also known as 5-methoxy-N,N-dimethylisotryptamine, is a putatively non-hallucinogenic serotonin 5-HT2A receptor agonist and psychoplastogen of the isotryptamine group. It is the isotryptamine analogue of the non-hallucinogenic 6-MeO-DMT and is a positional isomer of the psychedelic 6-MeO-isoDMT.
α-Methylisotryptamine is a synthetic compound belonging to the tryptamine class, known for its psychoactive properties. As a structural analog of α-methyltryptamine (αMT), isoAMT exhibits entactogenic and psychedelic effects.
isoDMT, also known as N,N-dimethylisotryptamine, is a putatively non-hallucinogenic serotonin 5-HT2A receptor agonist and psychoplastogen of the isotryptamine group. It is the isotryptamine homologue of dimethyltryptamine (DMT), a more well-known serotonergic psychedelic of the tryptamine family, and represents a small structural modification of DMT.
Ibogainalog (IBG), also known as 9-methoxyibogaminalog, is a serotonergic psychedelic and psychoplastogen related to ibogaine but with a simplified chemical structure.
