Racetams are a class of drugs that share a pyrrolidone nucleus. Some, such as piracetam, aniracetam, oxiracetam, pramiracetam and phenylpiracetam are considered nootropics. Others such as levetiracetam, brivaracetam, and seletracetam are anticonvulsants.
Phenylpiracetam, is a phenylated analog of the drug piracetam. It was developed in 1983 as a medication for Soviet Cosmonauts to treat the prolonged stresses of working in space. Phenylpiracetam was created at the Russian Academy of Sciences Institute of Biomedical Problems in an effort led by psychopharmacologist Valentina Ivanovna Akhapkina. In Russia it is now available as a prescription drug. Research on animals has indicated that phenylpiracetam may have anti-amnesic, antidepressant, anticonvulsant, anxiolytic, and memory enhancement effects.
Phenibut, sold under the brand names Anvifen, Fenibut, and Noofen among others, is a central nervous system depressant with anxiolytic effects, and is used to treat anxiety, insomnia, and for a variety of other indications. It is usually taken by mouth as a tablet, but may be given intravenously.
The sigma-1 receptor (σ1R), one of two sigma receptor subtypes, is a chaperone protein at the endoplasmic reticulum (ER) that modulates calcium signaling through the IP3 receptor. In humans, the σ1 receptor is encoded by the SIGMAR1 gene.
Desformylflustrabromine (dFBr) is a monomethyltryptamine derivative which was first isolated as a secondary metabolite of the marine bryozoan Flustra foliacea.
Metabotropic glutamate receptor 2 (mGluR2) is a protein that, in humans, is encoded by the GRM2 gene. mGluR2 is a G protein-coupled receptor (GPCR) that couples with the Gi alpha subunit. The receptor functions as an autoreceptor for glutamate, that upon activation, inhibits the emptying of vesicular contents at the presynaptic terminal of glutamatergic neurons.
The alpha-7 nicotinic receptor, also known as the α7 receptor, is a type of nicotinic acetylcholine receptor implicated in long-term memory, consisting entirely of α7 subunits. As with other nicotinic acetylcholine receptors, functional α7 receptors are pentameric [i.e., (α7)5 stoichiometry].
IDRA-21 is a positive allosteric modulator of the AMPA receptor and a benzothiadiazine derivative. It is a chiral molecule, with (+)-IDRA-21 being the active form.
LY-404187 is an AMPA receptor positive allosteric modulator which was developed by Eli Lilly and Company. It is a member of the biarylpropylsulfonamide class of AMPA receptor potentiators.
SIB-1893 is a drug used in scientific research which was one of the first compounds developed that acts as a selective antagonist for the metabotropic glutamate receptor subtype mGluR5. It has anticonvulsant and neuroprotective effects, and reduces glutamate release. It has also been found to act as a positive allosteric modulator of mGluR4.
CDPPB is a drug used in scientific research which acts as a positive allosteric modulator selective for the metabotropic glutamate receptor subtype mGluR5. It has antipsychotic effects in animal models, and mGluR5 modulators are under investigation as potential drugs for the treatment of schizophrenia, as well as other applications.
SKF-83,959 is a synthetic benzazepine derivative used in scientific research which acts as an agonist at the D1–D2 dopamine receptor heteromer. It behaves as a full agonist at the D1 protomer and a high-affinity partial agonist at the D2 protomer. It was further shown to act as an allosteric modulator of the sigma-1 receptor. SKF-83,959 additionally inhibits sodium channels as well as delayed rectifier potassium channels. SKF-83,959 is a racemate that consists of the R-(+)- and S-(−)-enantiomers MCL-202 and MCL-201, respectively.
Unifiram is an experimental drug. that has antiamnesic and other effects in animal studies with far greater potency than piracetam. A number of related compounds are known, such as sunifiram (DM-235) and sapunifiram (MN-19). Unifiram has two enantiomers, with the dextro form being the more active isomer. It has been shown to reduce the duration of hypnosis induced by pentobarbital, without impairing motor coordination. As of 2015, no formal human studies with unifiram have been conducted. Unifiram is not patented and, despite the lack of human and long-term toxicity studies, it is commonly sold online.
S-18986 is a positive allosteric modulator of the AMPA receptor related to cyclothiazide. It has nootropic and neuroprotective effects in animal studies, and induces both production of BDNF and AMPA-mediated release of noradrenaline and acetylcholine in the hippocampus and frontal cortex of the brain.
SB-206553 is a drug which acts as a mixed antagonist for the 5-HT2B and 5-HT2C serotonin receptors. It has anxiolytic properties in animal studies and interacts with a range of other drugs. It has also been shown to act as a positive allosteric modulator of α7 nicotinic acetylcholine receptors. Modified derivatives of SB-206553 have been used to probe the structure of the 5-HT2B receptor.
Neboglamine, formerly known as nebostinel, is a positive allosteric modulator of the glycine site of the NMDA receptor which is under investigation for Rottapharm for the treatment of schizophrenia and cocaine dependence. It shows cognition- and memory-enhancing effects in animal models. As of June 2015, it is in phase II clinical trials for both schizophrenia and cocaine abuse.
Ivars Kalviņš is a Latvian chemist who invented the drug meldonium, trade-named Mildronate.
Tulrampator is a positive allosteric modulator (PAM) of the AMPA receptor (AMPAR), an ionotropic glutamate receptor, which is under development by RespireRx Pharmaceuticals and Servier for the treatment of major depressive disorder, Alzheimer's disease, dementia, and mild cognitive impairment. Tulrampator was in phase II clinical trial for depression, but failed to show superiority over placebo. There are also phase II clinical trials for Alzheimer's disease and phase I trials for dementia and mild cognitive impairment.
SAGE-718 is experimental drug being investigated for the treatment of neurological disorders and cognitive impairment. It acts as a positive allosteric modulator of the NMDA receptor, whose activity is essential for learning, memory, and cognition. SAGE-718 is an analog of the neurosteroid 24S-hydroxycholesterol.
