SKF-38,393 is a synthetic compound of the benzazepine chemical class which acts as a selective D1/D5 receptor partial agonist. It has stimulant and anorectic effects.
Naphthylaminopropane (PAL-287) is an experimental drug under investigation as of 2007 for the treatment of alcohol and stimulant addiction.
Dopamine receptor D1, also known as DRD1. It is one of the two types of D1-like receptor family — receptors D1 and D5. It is a protein that in humans is encoded by the DRD1 gene.
UH-232 ((+)-UH232) is a drug which acts as a subtype selective mixed agonist-antagonist for dopamine receptors, acting as a weak partial agonist at the D3 subtype, and an antagonist at D2Sh autoreceptors on dopaminergic nerve terminals. This causes dopamine release in the brain and has a stimulant effect, as well as blocking the behavioural effects of cocaine. It may also serve as a 5-HT2A receptor agonist, based on animal studies. It was investigated in clinical trials for the treatment of schizophrenia, but unexpectedly caused symptoms to become worse.
RTI(-4229)-113 is a stimulant drug which acts as a potent and fully selective dopamine reuptake inhibitor (DRI). It has been suggested as a possible substitute drug for the treatment of cocaine addiction. "RTI-113 has properties that make it an ideal medication for cocaine abusers, such as an equivalent efficacy, a higher potency, and a longer duration of action as compared to cocaine." Replacing the methyl ester in RTI-31 with a phenyl ester makes the resultant RTI-113 fully DAT specific. RTI-113 is a particularly relevant phenyltropane cocaine analog that has been tested on squirrel monkeys. RTI-113 has also been tested against cocaine in self-administration studies for DAT occupancy by PET on awake rhesus monkeys. The efficacy of cocaine analogs to elicit self-administration is closely related to the rate at which they are administered. Slower onset of action analogs are less likely to function as positive reinforcers than analogues that have a faster rate of onset.
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.
6-Br-APB is a synthetic compound that acts as a selective D1 agonist, with the (R)-enantiomer being a potent full agonist, while the (S) enantiomer retains its D1 selectivity but is a weak partial agonist. (R)-6-Br-APB and similar D1-selective full agonists like SKF-81,297 and SKF-82,958 produce characteristic anorectic effects, stereotyped behaviour and self-administration in animals, with a similar but not identical profile to that of dopaminergic stimulants such as amphetamine.
A-77636 is a synthetic drug which acts as a selective D1 receptor full agonist. It has nootropic, anorectic, rewarding and antiparkinsonian effects in animal studies, but its high potency and long duration of action causes D1 receptor downregulation and tachyphylaxis, and unlike other D1 full agonists such as SKF-82,958, it does not produce place preference in animals. A-77636 partially substituted for cocaine in animal studies, and has been suggested for use as a possible substitute drug in treating addiction, but it is better known for its use in studying the role of D1 receptors in the brain.
A-68930 is a synthetic compound that acts as a selective dopamine receptor D1 agonist. It is orally active and has antidepressant and anorectic effects in animals, producing wakefulness and tachycardia, but without stimulant effects, instead producing sedation. The difference in effects between A-68930 and other D1 agonists such as SKF-82958 may be due to their differing effects on the related D5 receptor.
7-OH-DPAT is a synthetic compound that acts as a dopamine receptor agonist with reasonable selectivity for the D3 receptor subtype, and low affinity for serotonin receptors, unlike its structural isomer 8-OH-DPAT. 7-OH-DPAT is self-administered in several animal models, and is used to study addiction to cocaine.
SKF-81,297 is a synthetic drug of the benzazepine chemical class that acts as a selective dopamine D1/D5 receptor full agonist, and produces a characteristic stimulant-like pattern of anorexia, hyperactivity and self-administration in animals. This profile is shared with several related drugs such as 6-Br-APB and SKF-82,958, but not with certain other D1 full agonists such as A-77,636, reflecting functional selectivity of D1 activation. Newer findings reveal that SKF-81,297 additionally acts as a partial agonist at D1-D2 receptor heteromers.
A-86929 is a synthetic compound that acts as a selective dopamine receptor D1 agonist. It was developed as a possible treatment for Parkinson's disease, as well as for other applications such as treatment of cocaine addiction, but while it had reasonable efficacy in humans it also caused dyskinesias and has not been continued. It has mainly been used as its diacetate ester prodrug adrogolide (ABT-431), which has better bioavailability.
Roxindole (EMD-49,980) is a dopaminergic and serotonergic drug which was originally developed by Merck KGaA for the treatment of schizophrenia. In clinical trials its antipsychotic efficacy was only modest but it was unexpectedly found to produce potent and rapid antidepressant and anxiolytic effects. As a result, roxindole was further researched for the treatment of depression instead. It has also been investigated as a therapy for Parkinson's disease and prolactinoma.
SKF-77,434 is a drug which acts as a selective dopamine D1 receptor partial agonist, and has stimulant and anorectic effects. Unlike other D1 agonists with higher efficacy such as SKF-81,297 and 6-Br-APB, SKF-77,434 does not maintain self-administration in animal studies, and so has been researched as a potential treatment for cocaine addiction.
PNU-99,194(A) (or U-99,194(A)) is a drug which acts as a moderately selective D3 receptor antagonist with ~15-30-fold preference for D3 over the D2 subtype. Though it has substantially greater preference for D3 over D2, the latter receptor does still play some role in its effects, as evidenced by the fact that PNU-99,194 weakly stimulates both prolactin secretion and striatal dopamine synthesis, actions it does not share with the more selective (100-fold) D3 receptor antagonists S-14,297 and GR-103,691.
BP-897 is a drug used in scientific research which acts as a potent selective dopamine D3 receptor partial agonist with an in vitro intrinsic activity of ~0.6 and ~70x greater affinity for D3 over D2 receptors and is suspected to have partial agonist or antagonist activity in vivo. It has mainly been used in the study of treatments for cocaine addiction. A study comparing BP-897 with the potent, antagonistic, and highly D3 selective SB-277,011-A found, "SB 277011-A (1–10 mg/kg) was able to block cue-induced reinstatement of nicotine-seeking, indicating that DRD3 selective antagonism may be an effective approach to prevent relapse for nicotine. In contrast, BP 897 did not block the cue-induced reinstatement of nicotine-seeking or nicotine-taking under the FR5 schedule."
CY-208,243 is a drug which acts as a dopamine agonist selective for the D1 subtype. Unlike most D1-selective agonists, it shows efficacy in animal models of Parkinson's disease.
L-741,626 is a drug which acts as a potent and selective antagonist for the dopamine receptor D2. It has good selectivity over the related D3 and D4 subtypes and other receptors. L-741,626 is used for laboratory research into brain function and has proved particularly useful for distinguishing D2 mediated responses from those produced by the closely related D3 subtype, and for studying the roles of these subtypes in the action of cocaine and amphetamines in the brain.
OSU-6162 (PNU-96391) is a compound which acts as a partial agonist at both dopamine D2 receptors and 5-HT2A receptors. It acts as a dopamine stabilizer in a similar manner to the closely related drug pridopidine, and has antipsychotic, anti-addictive and anti-Parkinsonian effects in animal studies. Both enantiomers show similar activity but with different ratios of effects, with the (S) enantiomer (–)-OSU-6162 that is more commonly used in research, having higher binding affinity to D2 but is a weaker partial agonist at 5-HT2A, while the (R) enantiomer (+)-OSU-6162 has higher efficacy at 5-HT2A but lower D2 affinity.
Amesergide is a serotonin receptor antagonist of the ergoline and lysergamide families related to methysergide which was under development by Eli Lilly and Company for the treatment of a variety of conditions including depression, anxiety, schizophrenia, male sexual dysfunction, migraine, and thrombosis but was never marketed. It reached phase II clinical trials for the treatment of depression, erectile dysfunction, and premature ejaculation prior to the discontinuation of its development.
