Adrogolide is a chemically stable prodrug of the dopamine D1 receptor agonist A-86929. Adrogolide is rapidly converted in plasma to A-86929. A-86929 has high affinity and functional selectivity for the dopamine D1 receptor. Adrogolide has been in phase II clinical trials for the treatment of Parkinson's disease and cocaine abuse. However, this research has been discontinued. The adverse events associated with its use of adrogolide were of mild-to-moderate severity and included injection site reaction, asthenia, headache, nausea, vomiting, postural hypotension, vasodilitation, and dizziness.

Omigapil (CGP 3466 or TCH346) is a structurally related analog of R-(-)-deprenyl that exhibits virtually no monoamine oxidase type B inhibiting activity but is neuroprotective in the picomolar concentration range. It binds to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and at subnanomolar concentrations prevent the S-nitrosylation of GAPDH, inhibit GAPDH-Siah binding and prevent the nuclear translocation of GAPDH. Omigapil demonstrated promising potential in the treatment of Parkinson's disease and motoneuron disease in animal models, however, it did not show efficacy in clinical trials. Omigapil is in development for the treatment of congenital muscular dystrophy.

Remacemide is a low-affinity noncompetitive NMDA receptor antagonist with sodium channel blocking properties. It has been studied for a number of conditions including acute ischemic stroke, epilepsy, Parkinsons Disease, and Huntington's disease. It was concluded, that was unlikely that remacemide would be further developed as an antiepileptic drug. As for other conditions, there no any information in the literature, why remacemide is no longer being developed for them.

Mofegiline (MDL 72,974A or (E)-2-(4-fluorophenethyl)-3-fluoroallylamine, hydrochloride), is a selective and irreversible inhibitor of monoamine oxidase type B (MAO-B) both in vitro and in vivo. In addition, mofegiline inhibits semicarbazide-sensitive amine oxidase activity from human serum and saphenous vein. In phase II studies, MDL 72,974A is proving to be a useful adjunct to conventional therapy of Parkinson's disease. It seems mofegiline development was discontinued.

Traxoprodil (CP-101,606) is a potent, selective N-Methyl-D-aspartate (NMDA) receptor (NR2B subunit) antagonist under development by Pfizer for its potential as a neuroprotectant in head injury and neurodegenerative disease. It is in phase II trials in the US and in phase I in Japan for the potential treatment of head injury, such as, Depressive Disorder, Major and Parkinson's Disease. CP-101,606 does not protect against glutamate-induced neurotoxicity in cultured cerebellar neurons, up to a dose of 10 uM. These results are consistent with CP-101,606 being a potent NMDA antagonist, selective for the type of NMDA receptor associated with the hippocampus. Some further investigation revealed that CP-101,606 was associated with a dose-related dissociation and amnesia. These results support the hypothesis that glutamate antagonists may be useful antidyskinetic agents. However, future studies will have to determine if the benefits of dyskinesia suppression can be achieved without adverse cognitive effects.

Naxagolide (MK-458; L 647,339; (+)-PHNO) is a dopamine D2/D3-receptor agonist, which was studied for the treatment of patients with Parkinson's disease, but further study was discontinued. In addition, was discovered, that Naxagolide C-11 ([(11)C]-(+)-PHNO) was a potential radiotracer for imaging the high-affinity state of dopamine D2 receptors with positron emission tomography (PET) in human subjects. This radiotracer is a suitable for imaging the agonist binding sites (denoted D(2HIGH) and D(3)) of these receptors. PET studies in nonhuman primates documented that, in vivo, [(11)C]-(+)-PHNO displays a relative selectivity for D(3) compared with D(2HIGH) receptor sites and that the [(11)C]-(+)-PHNO signal is enriched in D(3) contribution compared with conventional ligands such as [(11)C] raclopride. Recently was published article reflects the relationship between social attachment and dopamine D2/3 receptor availability in the brains of healthy humans using [11C]-(+)-PHNO.

PHA-543613 was discovered by Pfizer and has been under development primarily as a potential treatment of schizophrenia. PHA-543613 acts as an agonist to the Neuronal acetylcholine receptor protein alpha-7 subunit. A single human trial was conducted in healthy human volunteers, but the compound has been studied extensively in rat models for schizophrenia as well as Parkinson's disease and Alzheimer's disease.

Imetit (S-[2-(4-(imidazolyl)ethyl]isothiourea) is a highly specific and potent histamine H3 receptor agonist. It is widely used to study H3-mediated signaling.

Bay 65-1942 free base (Bay 65-1942) is a selective inhibitor of IKKβ with IC50 value of 10 uM and Ki value of 2 nM. Bay 65-1942 has been reported to provide cardioprotection through specific suppression of NF-κB signaling. It also afforded potent neuroprotection against LPS-induced neurodegeneration through selective inhibition of NF-kappaB activation and may be of potential benefit in the treatment of PD.

Propylnorapomorphine is a potent and selective D2 receptor agonist. Propylnorapomorphine is used as a tool compound to label dopamine receptors in rodent brain, and elicits dopaminergic behavioural effects. It stimulates motor activity, induces stereotypic behaviour and sexual stimulation. Propylnorapomorphine was investigated in clinical trial against Parkinson's disease and schizophrenia