RESUMEN
The preclinical pharmacodynamic and pharmacokinetic properties of 4-methylbenzyl (3S, 4R)-3-fluoro-4-[(Pyrimidin-2-ylamino) methyl] piperidine-1-carboxylate (CERC-301), an orally bioavailable selective N-methyl-D-aspartate (NMDA) receptor subunit 2B (GluN2B) antagonist, were characterized to develop a translational approach based on receptor occupancy (RO) to guide CERC-301 dose selection in clinical trials of major depressive disorder. CERC-301 demonstrated high-binding affinity (K i, 8.1 nmol L(-1)) specific to GluN2B with an IC 50 of 3.6 nmol L(-1) and no off-target activity. CERC-301 efficacy was demonstrated in the forced swim test with an efficacy dose (ED 50) of 0.3-0.7 mg kg(-1) (RO, 30-50%); increase in locomotor activity was observed at ED 50 of 2 mg kg(-1), corresponding to an RO of 75%. The predicted 50% RO concentration (Occ50) in humans was 400 nmol L(-1), similar to that predicted for rat, dog, and monkey (300, 200, and 400 nmol L(-1), respectively). Safety pharmacology and neurotoxicity studies raised no specific safety concerns. A first-in-human study in healthy males demonstrated a dose-proportional pharmacokinetic profile, with T max of ~1 h and t 1/2 of 12-17 h. Based on the preclinical and pharmacodynamic data, doses of ≥8 mg in humans are hypothesized to have an acceptable safety profile and result in clinically relevant peak plasma exposure.
RESUMEN
A novel series of annulated tricyclic compounds was synthesized and evaluated as NMDA/NR2B antagonists. Structure-activity development was directed towards in vitro optimization of NR2B activity and selectivity over the hERG K(+) channel. Preferred compounds were subsequently evaluated for selectivity in an alpha(1)-adrenergic receptor binding counter-screen and a cell-based assay of NR2B activity.
Asunto(s)
Benzocicloheptenos/síntesis química , Neurotransmisores/síntesis química , Piridinas/síntesis química , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Benzocicloheptenos/química , Benzocicloheptenos/farmacología , Línea Celular , Canales de Potasio Éter-A-Go-Go/metabolismo , Humanos , Neurotransmisores/química , Neurotransmisores/farmacología , Piridinas/química , Piridinas/farmacología , Receptores de N-Metil-D-Aspartato/metabolismo , Relación Estructura-ActividadRESUMEN
A novel series of cyclic benzamidines was synthesized and shown to exhibit NR2B-subtype selective NMDA antagonist activity. Compound 29 is orally active in a carrageenan-induced rat hyperalgesia model of pain.
Asunto(s)
Benzamidinas/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Administración Oral , Animales , Benzamidinas/administración & dosificación , Benzamidinas/uso terapéutico , Antagonistas de Aminoácidos Excitadores/administración & dosificación , Modelos Biológicos , Dolor/tratamiento farmacológico , RatasRESUMEN
The discovery of a novel series of NR2B subtype selective N-methyl-d-aspartate (NMDA) antagonists is reported. Initial optimization of a high-throughput screening lead afforded an aminopyridine derivative 13 with significant NR2B antagonist potency but limited selectivity over hERG-channel and other off-target activities. Further structure-activity studies on the aminoheterocycle moiety and optimization of the carbamate led to the highly potent 2-aminopyrimidine derivative 20j with a significantly improved off-target activity profile and oral bioavailability in multiple species coupled with good brain penetration. Compound 20j demonstrated efficacy in in vivo rodent models of antinociception, allodynia, and Parkinson's disease.
Asunto(s)
Analgésicos/síntesis química , Encéfalo/metabolismo , Pirimidinas/síntesis química , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Administración Oral , Analgésicos/farmacocinética , Analgésicos/farmacología , Animales , Antiparkinsonianos/síntesis química , Antiparkinsonianos/farmacocinética , Antiparkinsonianos/farmacología , Disponibilidad Biológica , Línea Celular , Perros , Femenino , Lóbulo Frontal/metabolismo , Humanos , Masculino , Dimensión del Dolor , Pirimidinas/farmacocinética , Pirimidinas/farmacología , Ensayo de Unión Radioligante , Ratas , Ratas Sprague-Dawley , Relación Estructura-ActividadRESUMEN
Two classes of 5-substituted benzimidazoles were identified as potent antagonists of the NR2B subtype of the N-methyl-d-aspartate (NMDA) receptor. Selected compounds show very good selectivity versus the NR2A, NR2C, and NR2D subtypes of the NMDA receptor as well as versus hERG-channel activity and alpha(1)-adrenergic binding. Benzimidazole 37a shows excellent activity in the carrageenan-induced mechanical hyperalgesia assay in rats as well as good pharmacokinetic behavior in dogs.
Asunto(s)
Analgésicos/síntesis química , Bencimidazoles/síntesis química , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Analgésicos/farmacocinética , Analgésicos/farmacología , Animales , Bencimidazoles/farmacocinética , Bencimidazoles/farmacología , Encéfalo/metabolismo , Calcio/metabolismo , Carragenina , Línea Celular , Perros , Femenino , Humanos , Hiperalgesia/sangre , Hiperalgesia/inducido químicamente , Hiperalgesia/tratamiento farmacológico , Técnicas In Vitro , Masculino , Técnicas de Placa-Clamp , Ratas , Ratas Sprague-Dawley , Receptores de N-Metil-D-Aspartato/fisiología , Relación Estructura-ActividadRESUMEN
A novel series of benzamidines was synthesized and shown to exhibit NR2B-subtype selective NMDA antagonist activity. Compound 31 is orally active in a carrageenan-induced rat hyperalgesia model of pain and shows no motor coordination side effects.
Asunto(s)
Benzamidinas/farmacología , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Administración Oral , Animales , Benzamidinas/síntesis química , Carragenina , Evaluación Preclínica de Medicamentos , Hiperalgesia/tratamiento farmacológico , Dolor/tratamiento farmacológico , Desempeño Psicomotor/efectos de los fármacos , Ratas , Relación Estructura-ActividadRESUMEN
The synthesis and biological evaluation of a series of nonpeptidic small molecule antagonists of the human platelet thrombin receptor (PAR-1) are described. Optimization of the 5-amino-3-arylisoxazole lead resulted in an approximate 100-fold increase in potency. The most potent of these compounds (54) inhibits platelet activation with IC(50)s of 90 nM against the thrombin receptor agonist peptide (TRAP) and 510 nM against thrombin as the agonist. Further, antagonist 54 fully blocks platelet aggregation stimulated by 1 nM thrombin for 10 min.