Neurotoxins are toxins that are destructive to nerve tissue. Neurotoxins are an extensive class of exogenous chemical neurological insults that can adversely affect function in both developing and mature nervous tissue. The term can also be used to classify endogenous compounds, which, when abnormally contacted, can prove neurologically toxic. Though neurotoxins are often neurologically destructive, their ability to specifically target neural components is important in the study of nervous systems. Common examples of neurotoxins include lead, ethanol, glutamate, nitric oxide, botulinum toxin, tetanus toxin, and tetrodotoxin. Some substances such as nitric oxide and glutamate are in fact essential for proper function of the body and only exert neurotoxic effects at excessive concentrations.
2,5-Dimethoxy-4-iodoamphetamine (DOI) is a psychedelic drug and a substituted amphetamine. Unlike many other substituted amphetamines, however, it is not primarily a stimulant. DOI has a stereocenter and R-(−)-DOI is the more active stereoisomer. In neuroscience research, [125I]-R-(−)-DOI is used as a radioligand and indicator of the presence of 5-HT2A serotonin receptors. DOI's effects have been compared to LSD, although there are differences that experienced users can distinguish. Besides the longer duration, the trip tends to be more energetic than an LSD trip, with more body load and a different subjective visual experience. The after effects include residual stimulation and difficulty sleeping, which, depending on the dose, may persist for days. While rare, it is sometimes sold as a substitute for LSD, or even sold falsely as LSD, which may be dangerous because DOI does not have the same established safety profile as LSD.
4-Fluoroamphetamine, also known as para-fluoroamphetamine (PFA) is a psychoactive research chemical of the phenethylamine and substituted amphetamine chemical classes. It produces stimulant and entactogenic effects. As a recreational drug, 4-FA is sometimes sold along with related compounds such as 2-fluoroamphetamine and 4-fluoromethamphetamine.
4-Methylthioamphetamine (4-MTA) is a designer drug of the substituted amphetamine class developed in the 1990s by a team led by David E. Nichols, an American pharmacologist and medical chemist, at Purdue University. It acts as a non-neurotoxic highly selective serotonin releasing agent (SSRA) in animals. 4-MTA is the methylthio derivative of amphetamine.
4-Fluoromethamphetamine (4-FMA) is a stimulant drug related to methamphetamine and 4-fluoroamphetamine. It has been reported to be sold as a designer drug, but little is known about its pharmacology or toxicology. It was first detected from legal highs sold in Japan in 2006 and became illegal to sell or to possess for the purpose of distribution in Japan in 2008. It was initially reported to be contained as an ingredient in some of the range of party pills sold internationally by the Israeli company Neorganics from around 2006 onwards, but this was later shown to be incorrect and this ingredient was eventually identified as the closely related compound 2-fluoromethamphetamine.
para-Chloroamphetamine (PCA), also known as 4-chloroamphetamine (4-CA), is a substituted amphetamine and monoamine releaser similar to MDMA, but with substantially higher neurotoxicity, thought to be due to the unrestrained release of both serotonin and dopamine by a metabolite. It is used as a neurotoxin by neurobiologists to selectively kill serotonergic neurons for research purposes, in the same way that 6-hydroxydopamine is used to kill dopaminergic neurons.
MDAI (5,6-methylenedioxy-2-aminoindane) is a drug developed in the 1990s by a team led by David E. Nichols at Purdue University. It acts as a non-neurotoxic and highly selective serotonin releasing agent (SSRA) in vitro and produces entactogen effects in humans.
5-Methoxy-6-methyl-2-aminoindane (MMAI) is a drug developed in the 1990s by a team led by David E. Nichols at Purdue University. It acts as a non-neurotoxic and highly selective serotonin releasing agent (SSRA) and produces entactogen effects in humans. It has been sold as a designer drug and research chemical online since 2010.
5-Iodo-2-aminoindane (5-IAI) is a drug which acts as a releasing agent of serotonin, norepinephrine, and dopamine. It was developed in the 1990s by a team led by David E. Nichols at Purdue University. 5-IAI fully substitutes for MDMA in rodents and is a putative entactogen in humans. Unlike related aminoindane derivatives like MDAI and MMAI, 5-IAI causes some serotonergic neurotoxicity in rats, but is substantially less toxic than its corresponding amphetamine homologue pIA, with the damage observed barely reaching statistical significance.
4-Methylamphetamine is a stimulant and anorectic drug of the phenethylamine and amphetamine chemical classes.
para-Bromoamphetamine (PBA), also known as 4-bromoamphetamine (4-BA), is an amphetamine derivative which acts as a serotonin-norepinephrine-dopamine releasing agent (SNDRA) and produces stimulant effects.
6-Chloro-2-aminotetralin (6-CAT) is a drug which acts as a selective serotonin releasing agent (SSRA) and is a putative entactogen in humans. It is a rigid analogue of para-chloroamphetamine (PCA).
2,5-Dimethoxy-4-fluoroamphetamine (DOF) is a psychedelic drug of the phenethylamine and amphetamine classes. Alexander Shulgin briefly describes DOF in his book PiHKAL:
Animal studies that have compared DOF to the highly potent DOI and DOB imply that the human activity will be some four to six times less than these two heavier halide analogues.
4-Chlorophenylisobutylamine, also known as 4-chloro-α-ethylphenethylamine, is an entactogen and stimulant drug of the phenethylamine class. It is an analogue of para-chloroamphetamine (PCA) where the alpha position methyl has been replaced with an ethyl group.
3,4-Dichloroamphetamine (DCA), is an amphetamine derived drug invented by Eli Lilly in the 1960s, which has a number of pharmacological actions. It acts as a highly potent and selective serotonin releasing agent (SSRA) and binds to the serotonin transporter with high affinity, but also acts as a selective serotonergic neurotoxin in a similar manner to the related para-chloroamphetamine, though with slightly lower potency. It is also a monoamine oxidase inhibitor (MAOI), as well as a very potent inhibitor of the enzyme phenylethanolamine N-methyl transferase which normally functions to transform noradrenaline into adrenaline in the body.
para-Chloromethamphetamine is a stimulant that is the N-methyl derivative and prodrug of the neurotoxic drug para-chloroamphetamine (4-CA). It has been found to decrease serotonin in rats. Further investigation into the long-term effects of chloroamphetamines discovered that administration of 4-CMA caused a prolonged reduction in the levels of serotonin and the activity of tryptophan hydroxylase in the brain one month after injection of a single dose of the drug.
4-Chloromethcathinone is a stimulant drug of the cathinone class that has been sold online as a designer drug.
The substituted benzofurans are a class of chemical compounds based on the heterocyclyc and polycyclic compound benzofuran. Many medicines use the benzofuran core as a scaffold, but most commonly the term is used to refer to the simpler compounds in this class which include numerous psychoactive drugs, including stimulants, psychedelics and empathogens. In general, these compounds have a benzofuran core to which a 2-aminoethyl group is attached, and combined with a range of other substituents. Some psychoactive derivatives from this family have been sold under the name Benzofury.
Guanitoxin (GNT), formerly known as anatoxin-a(S) "Salivary", is a naturally occurring cyanotoxin commonly isolated from cyanobacteria. It is a potent covalent acetylcholinesterase inhibitor, and thus a potent rapid acting neurotoxin which in cases of severe exposure can lead to death. Guanitoxin was first structurally characterized in 1989, and consists of a cyclic N-hydroxyguanine organophosphate with a phosphate ester moiety.
