Frank S Menniti

• Ph.D.
• CSO at MindImmune Therapeutics, Kingston RI, USA

N-methyl-D-aspartate (NMDA)-induced spine shrinkage proceeds independently of ion flux and requires the initiation of de novo protein synthesis. Using subtype-selective pharmacological and genetic tools, we find that structural plasticity is dependent on ligand binding to GluN2B-containing NMDA receptors (NMDARs) and signaling via the GluN2B carbox...

NMDA-type ionotropic glutamate receptors are critically involved in excitatory neurotransmission and their dysfunction is implicated in many brain disorders. Allosteric modulators with selectivity for specific NMDA receptor subtypes are therefore attractive as therapeutic agents, and sustained drug discovery efforts have resulted in a wide range of...

Background: Tourette syndrome is a neurodevelopmental movement disorder involving basal ganglia dysfunction. PDE10A inhibitors modulate signaling in the striatal basal ganglia nuclei and are thus of interest as potential therapeutics in treating Tourette syndrome and other movement disorders. Methods: The preclinical pharmacology and toxicology, hu...

N-methyl-D-aspartate (NMDA) receptors mediate a slow component of excitatory synaptic transmission, are widely distributed throughout the central nervous system, and regulate synaptic plasticity. NMDA receptor modulators have long been considered as potential treatments for psychiatric disorders including depression and schizophrenia, neurodevelopm...

Many physiologic effects of l-glutamate, the major excitatory neurotransmitter in the mammalian central nervous system, are mediated via signaling by ionotropic glutamate receptors (iGluRs). These ligand-gated ion channels are critical to brain function and are centrally implicated in numerous psychiatric and neurologic disorders. There are differe...

PDE10A, a phosphodiesterase that inactivates both cAMP and cGMP, is a unique signaling molecule in being highly and nearly exclusively expressed in striatal medium spiny neurons. These neurons dynamically integrate cortical information with dopamine-signaled value to mediate action selection among available behavioral options. Medium spiny neurons...

NMDA receptors containing GluN2D subunits are expressed in the subthalamic nucleus and external globus pallidus, key nuclei of the indirect and hyperdirect pathways of the basal ganglia. This circuitry integrates cortical input with dopaminergic signaling to select advantageous behaviors among available choices. In the experiments described here, w...

NMDA receptors are ionotropic glutamate receptors that mediate excitatory neurotransmission. The diverse functions of these receptors are tuned by deploying different combinations of GluN1 and GluN2 subunits (GluN2A-D) to form either diheteromeric NMDA receptors, which contain two GluN1 and two identical GluN2 subunits, or triheteromeric NMDA recep...

PDE9A is a cGMP-specific phosphodiesterase expressed in neurons throughout the brain that has attracted attention as a therapeutic target to treat cognitive disorders. Indeed, PDE9A inhibitors are under evaluation in clinical trials as a treatment for Alzheimer’s disease and schizophrenia. However, little is known about the cGMP signaling cascades...

We disclose the discovery and X-ray co-crystal data of potent, selective quinazoline inhibitors of PDE1. Inhibitor (S)-3 readily attains free plasma concentrations above PDE1 IC50 values and has restricted brain access. The racemic compound 3 inhibits >75% of PDE hydrolytic activity in soluble samples of human myocardium, consistent with heightened...

3’,5’-cyclic nucleotide phosphodiesterases (PDEs) degrade cAMP and cGMP, with PDE9A having the highest affinity for cGMP. We show PDE9A6 and three novel PDE9 isoforms (PDE9X-100, PDE9X-120, PDE9X-175) are reliably detected in brain and lung of mouse, while PDE9A2 and other isoforms are found elsewhere. PDE9A localizes to the membrane in all organs...

NMDA-type glutamate receptors are ligand-gated ion channels that mediate a major component of excitatory neurotransmission in the central nervous system (CNS). They are widely distributed at all stages of development and are critically involved in normal brain functions, including neuronal development and synaptic plasticity. NMDA receptors are als...

NMDA receptors mediate excitatory synaptic transmission and regulate synaptic plasticity in the central nervous system, but their dysregulation is also implicated in numerous brain disorders. Here, we describe GluN2A-selective negative allosteric modulators (NAMs) that inhibit NMDA receptors by stabilizing the apo state of the GluN1 ligand-binding...

GluN2A is the most abundant of the GluN2 NMDA receptor subunits in the mammalian CNS. Physiological and genetic evidence implicate GluN2A-containing receptors in susceptibility to autism, schizophrenia, childhood epilepsy and neurodevelopmental disorders such as Rett Syndrome. However, GluN2A-selective pharmacological probes to explore the therapeu...

GluN2A subunit-containing NMDA receptors are the most abundant in the mammalian CNS and physiological and genetic evidence implicate these receptors in susceptibility to autism, schizophrenia, childhood epilepsy and neurodevelopmental disorders such as Rett Syndrome. However, GluN2A-selective pharmacological probes to explore the therapeutic potent...

Ketamine, a pan-NMDA receptor channel blocker, and CP-101,606, an NR2B-selective negative allosteric modulator, have antidepressant effects in humans that develop rapidly after the drugs are cleared from the body. It has been proposed that the antidepressant effect of ketamine results from delayed synaptic potentiation. To further investigate this...

Neuroscience has made tremendous progress delineating the cellular and molecular processes important for understanding neuronal development and behavior, but this knowledge has been slow to translate to new treatments for psychiatric illness. To accelerate this transfer of knowledge to the human condition requires the wide-scale adoption of biomark...

PDE1 is a family of calcium-activated, dual substrate phosphodiesterases expressed in both the CNS and periphery that play a role in the integration of intracellular calcium and cyclic nucleotide signaling cascades. Exploration of the potential in targeting this family of enzymes to treat neuropsychiatric disorders has been hampered by a lack of po...

The pharmacological targeting of different phosphodiesterase (PDE) isoforms is predicted to have diverse, isoform-specific effects on central nervous system (CNS) function, and some of these effects may be relevant to the treatment of psychiatric and neurological disorders. The investigation of such possibilities is critically dependent on the avai...

Phosphodiesterase 10A (PDE10A) is highly expressed in striatal medium spiny neurons of both the direct and indirect output pathways. Similar to dopamine D2 receptor antagonists acting on indirect pathway neurons, PDE10A inhibitors have shown behavioral effects in rodent models that predict antipsychotic efficacy. These findings have supported the c...

α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor (AMPAR) positive allosteric modulation (i.e. "potentiation") has been proposed to overcome cognitive impairments in schizophrenia, but AMPAR overstimulation can be excitotoxic. Thus, it is critical to define carefully a potentiator's mechanism-based therapeutic index (TI) and to d...

Introduction: The second messengers cAMP and cGMP mediate fundamental aspects of brain function relevant to memory, learning, and cognitive functions. Consequently, cyclic nucleotide phosphodiesterases (PDEs), the enzymes that inactivate the cyclic nucleotides, are promising targets for the development of cognition-enhancing drugs. Areas covered:...

Research in therapeutics of neuropsychiatric disorders is increasingly focusing on drugs with new mechanisms of action, and such agents are often assessed in preclinical studies using nonhuman primates. However, researchers lack a standardized method to compare distinct drugs for common adverse effects on the nervous system. We have developed a new...

Schizophrenia is a highly debilitating, mental disorder which afflicts approximately 1% of the global population. Cognitive and negative deficits account for the lifelong disability associated with schizophrenia, whose symptoms are not effectively addressed by current treatments. New medicines are needed to treat these aspects of the disease. Neuro...

The phosphodiesterases (PDEs) are a superfamily of enzymes that regulate spatio-temporal signaling by the intracellular second messengers cAMP and cGMP. PDE2A is expressed at high levels in the mammalian brain. To advance our understanding of the role of this enzyme in regulation of neuronal signaling, we here describe the distribution of PDE2A in...

Phosphodiesterase 9A inhibitors have shown activity in preclinical models of cognition with potential application as novel therapies for treating Alzheimer's disease. Our clinical candidate, PF-04447943 (2), demonstrated acceptable CNS permeability in rats with modest asymmetry between central and peripheral compartments (free brain/free plasma = 0...

6-[(3S,4S)-4-Methyl-1-(pyrimidin-2-ylmethyl)pyrrolidin-3-yl]-1-(tetrahydro-2H-pyran-4-yl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyrimidin-4-one (PF-04447943) is a novel PDE9A inhibitor identified using parallel synthetic chemistry and structure-based drug design (SBDD) and has advanced into clinical trials. Selectivity for PDE9A over other PDE family membe...

Phosphodiesterase 5A (PDE5A) inhibitors improve functional recovery in experimental models of stroke in rats when treatment is delayed and without effect on infarct volume. PDE5A is expressed to only a very limited extent in forebrain tissues, raising the possibility that the locus of effect for the inhibitors is outside the brain. To start to addr...

There has been an increasing interest in the development of phosphodiesterase (PDE) inhibitors for the treatment of cognitive dysfunctions. In this editorial, the mechanism of action of PDEs is briefly described, while the effects of different PDE inhibitors in preclinical models are reviewed. Based on the expression of PDE mRNA in the human brain,...

A promising target for memory improvement is phosphodiesterase type 5 (PDE5), which selectively hydrolyzes cyclic guanosine monophosphate (cGMP). In rodents, PDE5 inhibitors (PDE5-Is) have been shown to improve memory performance in many behavioral paradigms. However, it is questioned whether the positive effects in animal studies result from PDE5...

Cyclic nucleotides are critical regulators of synaptic plasticity and participate in requisite signaling cascades implicated across multiple neurotransmitter systems. Phosphodiesterase 9A (PDE9A) is a high-affinity, cGMP-specific enzyme widely expressed in the rodent central nervous system. In the current study, we observed neuronal staining with a...

Utilizing structure-based virtual library design and scoring, a novel chimeric series of phosphodiesterase 10A (PDE10A) inhibitors was discovered by synergizing binding site interactions and ADME properties of two chemotypes. Virtual libraries were docked and scored for potential binding ability, followed by visual inspection to prioritize analogs...

Background: Huntington's disease is a devastating neurodegenerative condition for which there is no therapy to slow disease progression. The particular vulnerability of striatal medium spiny neurons to Huntington's pathology is hypothesized to result from transcriptional dysregulation within the cAMP and CREB signaling cascades in these neurons. T...

The mammalian ionotropic glutamate receptor family encodes 18 gene products that coassemble to form ligand-gated ion channels containing an agonist recognition site, a transmembrane ion permeation pathway, and gating elements that couple agonist-induced conformational changes to the opening or closing of the permeation pore. Glutamate receptors med...

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Working memory impairments are a core aspect of schizophrenia, yet current medicines do not address such cognitive dysfunction. We have developed a model of these working memory deficits by acutely disrupting glutamatergic synaptic transmission by administration of the N-methyl-d-aspartate (NMDA) antagonist ketamine in the nonhuman primate. The cur...

PDE10A is a member of the phosphodiesterase superfamily highly enriched within medium spiny neurons (MSN) in mammalian striatum. We have used inhibitors of PDE10A and quantitative measures of mRNA to demonstrate that PDE10A controls striatal gene expression by regulating MSN cyclic nucleotide signaling pathways. Acute treatment with PDE10A inhibito...

By use of chemical enablement and prospective design, a novel series of selective, brain penetrant PDE9A inhibitors have been identified that are capable of producing in vivo elevations of brain cGMP.

Phosphodiesterase 5A (PDE5A) inhibitors improve functional recovery after middle cerebral artery occlusion (MCA-o) in rats. We used the PDE5A inhibitor 3-(4-(2-hydroxyethyl)piperazin-1-yl)-7-(6-methoxypyridin-3-yl)-1-(2-propoxyethyl)pyrido[3,4-b]pyrazin-2(1H)-one hydrochloride (PF-5) to determine the timing, duration, and degree of inhibition that...

We report the X-ray crystal structure of a phosphodiesterase (PDE) that includes both catalytic and regulatory domains. PDE2A (215-900) crystallized as a dimer in which each subunit had an extended organization of regulatory GAF-A and GAF-B and catalytic domains connected by long alpha-helices. The subunits cross at the GAF-B/catalytic domain linke...

Utilizing structure-based drug design, a 4-aminoimidazole heterocyclic core was synthesized as a replacement for a 2-aminothiazole due to potential metabolically mediated toxicity. The synthetic route utilized allowed for ready synthesis of 1-substituted-4-aminoimidazoles. SAR exploration resulted in the identification of a novel cis-substituted cy...

PDE10A is a dual substrate PDE that is highly expressed in medium spiny neurons of the striatal complex. The inhibition of PDE10A produces effects that modulate basal ganglia function in ways that suggest a particular therapeutic utility in the treatment of psychosis in schizophrenia. Significant understanding of PDE10A at the molecular level has h...

By utilizing structure-based drug design (SBDD) knowledge, a novel class of phosphodiesterase (PDE) 10A inhibitors was identified. The structure-based drug design efforts identified a unique "selectivity pocket" for PDE10A inhibitors, and interactions within this pocket allowed the design of highly selective and potent PDE10A inhibitors. Further op...

Phosphodiesterases (PDEs) comprise a family of enzymes that regulate the levels of cyclic nucleotides, key second messengers that mediate a diverse array of functions. PDE2A is an evolutionarily conserved cGMP-stimulated cAMP and cGMP PDE. In the present study, the regional and cellular distribution of PDE2A in tissues of rats, mice, cynomolgus mon...

It is well established that cAMP signaling is an important regulator of the oocyte meiotic cell cycle. Conversely, the function of cGMP during oocyte maturation is less clear. Herein, we evaluated the expression of cGMP-hydrolyzing phosphodiesterases (PDEs) in the somatic and germ cell compartments of the mouse ovarian follicle and demonstrate that...

Decreased activity of cAMP responsive element-binding protein (CREB) is thought to contribute to the death of striatal medium spiny neurons in Huntington's disease (HD). Therefore, therapies that increase levels of activated CREB, may be effective in fighting neurodegeneration in HD. In this study, we sought to determine whether the phosphodiestera...

The cyclic nucleotide phosphodiesterase 10A (PDE10A) is highly expressed in striatal medium-sized spiny projection neurons (MSNs), apparently playing a critical role in the regulation of both cGMP and cAMP signaling cascades. Genetic disruption or pharmacological inhibition of PDE10A reverses behavioral abnormalities associated with subcortical hyp...

This randomized, placebo-controlled, double-blind study was the first to evaluate the antidepressant efficacy, safety, and tolerability of an NR2B subunit-selective N-methyl-D-aspartate receptor antagonist, CP-101,606. Subjects had major depression, according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria and a hi...

Glutamate antagonists decrease dyskinesia and augment the antiparkinsonian effects of levodopa in animal models of Parkinson's disease (PD). In a randomized, double-blind, placebo-controlled clinical trial, we investigated the acute effects of placebo and two doses of a NR2B subunit selective NMDA glutamate antagonist, CP-101,606, on the response t...

The phosphodiesterases (PDEs) are metal ion-dependent enzymes that regulate cellular signaling by metabolic inactivation of the ubiquitous second messengers cAMP and cGMP. In this role, the PDEs are involved in many biological and metabolic processes and are proven targets of successful drugs for the treatments of a wide range of diseases. However,...

We have recently proposed the hypothesis that inhibition of the cyclic nucleotide phosphodiesterase (PDE) 10A may represent a new pharmacological approach to the treatment of schizophrenia (Curr Opin Invest Drug 8:54-59, 2007). PDE10A is highly expressed in the medium spiny neurons of the mammalian striatum (Brain Res 985:113-126, 2003; J Histochem...

Schizophrenia has a complex genetic underpinning and variations in a number of candidate genes have been identified that confer risk of developing the disorder. We report in the present studies that several single nucleotide polymorphisms (SNPs) and a two-SNP haplotype in PDE4B are associated with an increased incidence of schizophrenia in two larg...

Chiral pyrazoline amino acids (3aR,4S,6aR)-1a and (3aR,4S,6aR)-1b, and (3aS,6S,6aS)-2a and (3aS,6S,6aS)-2b, which are conformationally constrained analogues of glutamic and homoglutamic acid, respectively, were prepared via a strategy based on the 1,3-dipolar cycloaddition of a nitrile imine to methyl N-Boc-3,4-didehydro-(S)-prolinate. The new ‘ami...

Development of N-methyl-D-aspartate (NMDA) antagonists for a variety of disorders has been hindered by their production of phencyclidine (PCP)-like psychological effects and abuse potential. There is, however, evidence to suggest that this problem might be mitigated by targeting NMDA receptors subtypes, in particular, those containing the NR2B subu...

Drugs acting at cannabinoid type 1 receptors (CB1) have modulatory effects on glutamate and GABA neurotransmission in basal ganglia; thus, they potentially affect motor behavior in the parkinsonian setting. Preclinical trials with diverse cannabinoid agents have shown varied results, and the precise effects of blocking cannabinoid CB1 receptors rem...

It is becoming well established that metabolic inactiva-tion of the cyclic nucleotides cAMP and cGMP is intimately involved in the regulation of cyclic nucleotide-mediated signaling cascades. There are four families of PDEs that metabolize cGMP, PDE1, PDE2, PDE9, and PDE10, that are prominently and differentially expressed in the central nervous sy...

Cyclic nucleotide signalling plays a key role in regulating neurite outgrowth in developmental and injury settings. The functional consequences of enhanced cyclic nucleotide signalling on processes that contribute to neurite outgrowth varies across neuronal cell type, age, cellular environment, and endpoints evaluated. We have evaluated the potenti...

Estradiol protects against striatal dopamine terminal loss caused by the neurotoxin MPTP in mice. This effect of estradiol is thought to be mediated by an interaction with estrogen receptors (ER), of which there are two: ERalpha and ERbeta. In the present study, the role of these two ERs in MPTP toxicity and its neuroprotection by estradiol was inv...

A disruption of corticostriatal signaling is believed to underlie the psychotic symptoms of schizophrenia and also contribute to many of the cognitive deficits associated with this disorder. Phosphodiesterase (PDE)10A is a dual substrate PDE highly expressed in striatal medium spiny neurons. Biochemical and behavioral studies indicate that the inhi...

A papaverine based pharmacophore model for PDE10A inhibition was generated via SBDD and used to design a library of 4-amino-6,7-dimethoxyquinazolines. From this library emerged an aryl ether pyrrolidyl 6,7-dimethoxyquinazoline series that became the focal point for additional modeling, X-ray, and synthetic efforts toward increasing PDE10A inhibitor...

The neurotoxin MPTP is widely used to cause damage to the dopaminergic system in rodents and non-human primates to model various aspects of Parkinson's disease. In mice, depletion of striatal dopamine is the commonly used endpoint to assess neuronal damage. However, it has proved technically challenging to quantify dopaminergic cell bodies as an in...

A monoclonal antibody directed against the amino terminal of rat phosphodiesterase 10A (PDE10A) was used to localize PDE10A in multiple central nervous system (CNS) and peripheral tissues from mouse, rat, dog, cynomolgus macaque, and human. PDE10A immunoreactivity is strongly expressed in the CNS of these species with limited expression in peripher...

The therapeutic and commercial success of phosphodiesterase 5 inhibitors such as Viagra, Levitra and Cialis has sparked renewed interest in the phosphodiesterases as drug discovery targets. Virtually all the phosphodiesterases are expressed in the CNS, making this gene family a particularly attractive source of new targets for the treatment of psyc...

Phosphodiesterase 10A (PDE10A) is a recently identified cyclic nucleotide phosphodiesterase expressed primarily in dopaminoreceptive medium spiny neurons of the striatum. We report that papaverine is a potent, specific inhibitor of PDE10A and use this compound to explore the role of PDE10A in regulating striatal function. Papaverine administration...

PDE10A is a newly identified phosphodiesterase that is highly expressed by the medium spiny projection neurons of the striatum. In order to investigate the physiological role of PDE10A in the central nervous system, PDE10A knockout mice (PDE10A(-/-)) were characterized both behaviorally and neurochemically. PDE10A(-/-) mice showed decreased explora...

Alzheimer's disease;CP-101,606;Excitotoxicity;Glutamate;Head trauma;NMDA receptors;NMDA receptor antagonists;Parkinson's disease;Stroke

PDE10A is a recently identified phosphodiesterase that is highly expressed by the GABAergic medium spiny projection neurons of the mammalian striatum. Inhibition of PDE10A results in striatal activation and behavioral suppression, suggesting that PDE10A inhibitors represent a novel class of antipsychotic agents. In the present studies we further el...

This paper describes the synthesis of racemic 3,5-dihydro-5-methyl-7,8-methylenedioxy-4H-2,3-benzodiazepin-4-one (+/-)-5, attempted stereoselective synthesis of its enantiomers, chiral HPLC resolution of the racemate, and assignment of the absolute configuration. Enantiomer (5S)-(-)-5 is provided with an in vivo anticonvulsant activity 8 times high...

A series of 1-aryl-3,5-dihydro-7,8-ethylenedioxy-4H-2,3-benzodiazepin-4-ones 2a-f, were synthesized and screened as anticonvulsant agents in DBA/2 mice against sound-induced seizures. The new compounds display anticonvulsant properties although the ED(50) values are higher than those of prototypes 1-aryl-3,5-dihydro-7,8-methylenedioxy-4H-2,3-benzod...

AMPA-type glutamate receptors are specifically inhibited by the noncompetitive antagonists GYKI-53655 and CP-465,022, which act through sites and mechanisms that are not understood. Using receptor mutagenesis, we found that these antagonists bind at the interface between the S1 and S2 glutamate binding core and channel transmembrane domains, specif...

A series of 2-semicarbazonomethyl-4,5-methylenedioxyphenylacetic acids (12-19) were synthesized and tested as anticonvulsant agents in DBA/2 mice against sound-induced seizures and the results compared to those previously reported for the corresponding methyl esters (4-11). The new compounds possess anticonvulsant properties lower than those of 4-1...

High-throughput screening with cyclin-dependent kinase 5 (cdk5)/p25 led to the discovery of N-(5-isopropyl-thiazol-2-yl)isobutyramide (1). This compound is an equipotent inhibitor of cdk5 and cyclin-dependent kinase 2 (cdk2)/cyclin E (IC(50)=ca. 320nM). Parallel and directed synthesis techniques were utilized to explore the SAR of this series. Up t...

In Parkinson's disease (PD), degeneration of the dopaminergic nigrostriatal pathway leads to enhanced transmission at NMDA receptors containing NR2B subunits. Previous studies have shown that some, but not all, NR2B-containing NMDA receptor antagonists alleviate parkinsonian symptoms in animal models of PD. Furthermore, enhanced NMDA receptor-media...

Sensitization of NMDA receptors containing the NR2B subunit has been increasingly associated with various forms of synaptic plasticity, including those implicated in the pathogenesis of extrapyramidal motor dysfunction. To determine whether activation of NR2B containing receptors contributes to the development and maintenance of levodopa-induced re...

For Abstract see ChemInform Abstract in Full Text.

5-(4-Aminobenzyl)-7,9-dihydro-8H-[1,3]dioxolo[4,5-h][2,3] benzodiazepin-8-one (3) and 7,9-dihydro-5-[2-(pyridin-2-yl)-vinyl]-8H-[1,3]dioxolo[4,5-h][2,3] benzodiazepin-8-one (4) were synthesized and screened as anticonvulsant agents in DBA/2 mice against sound-induced seizures. The new compounds are provided with anticonvulsant properties even if ED...

A set of novel 1-aryl-6,7-methylenedioxy-3H-quinazolin-4-(thi)ones (3a-f) has been designed and screened as anticonvulsant agents in DBA/2 mice. The new compounds are provided with anticonvulsant properties comparable to those of GYKI 52466. To clarify the mode of action, their affinity for the quinazolinone/2,3-benzodiazepine site of the AMPA rece...

PDE10A is a newly identified cAMP/cGMP phosphodiesterase for which mRNA is highly expressed in the mammalian striatum. In the present study, PDE10A protein and mRNA expression throughout the rat brain were determined, using a monoclonal antibody (24F3.F11) for Western blot and immunohistochemical analyses and an antisense riboprobe for in situ hybr...

The role of dopamine D3 receptors was investigated in mediating the neuroprotective effect of the dopamine D2/D3 receptor agonist (S)-2-amino-4,5,6,7-tetrahydro-6-propylamine-benzothiazole (pramipexole) in vivo. Pramipexole retained the ability to inhibit 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced dopamine depletion in mice in whic...

Epidemiological data suggest that the steroid hormone 17beta-estradiol plays an important role in protecting the brain from neurodegenerative processes, including that causing the loss of dopamine (DA) neurons in Parkinson's disease. Determining the mechanisms of neuroprotection in experimental systems may facilitate the development of estrogenic t...

A selected set of 1-aryl-7,8-methylenedioxy-2,3-benzodiazepin-4-ones and their analogues were evaluated for their ability to bind the competitive and noncompetitive sites of the AMPA receptors complex as well as to the glycine site of the NMDA receptors. The results put in evidence that most of the test compounds, despite a close structural similar...

Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor inhibition has been hypothesized to provide neuroprotective efficacy after cerebral ischemia on the basis of the activity in experimental ischemia models of a variety of compounds with varying selectivity for AMPA over other glutamate receptor subtypes. CP-465,022 is a new, po...

The hypothesis that aberrant alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor activity contributes to epileptogenesis and neurodegeneration has prompted the search for AMPA receptor antagonists as potential therapeutics to treat these conditions. We describe the functional characterization of a novel quinazolin-4-one AMPA re...

A series of 6-fluoro-3-(2 -chlorophenyl)quinazolin-4-ones has been prepared, which contains a 2-fluorophenyl ring attached to C-2 by a variety of two-atom tethers. These compounds were used to probe the structure-activity relationship (SAR) for AMPA receptor inhibition. The relative potencies of the new compounds ranged from 11 nM. to greater than...

Piriqualone (1) was found to be an antagonist of AMPA receptors. Structure activity optimization was conducted on each of the three rings in 1 to afford a series of potent and selective antagonists. The sterically crowded environment surrounding the N-3 aryl group provided sufficient thermal stability for atropisomers to be isolated. Separation of...

The alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor is an ionotropic glutamate receptor that mediates fast excitatory synaptic transmission throughout the central nervous system. In addition to the glutamate binding site, allosteric modulatory sites on the receptor are inferred from the ability of synthetic compounds to aff...