RESUMEN
6-Phenylnicotinamide (2) was previously identified as a potent TRPV1 antagonist with activity in an in vivo model of inflammatory pain. Optimization of this lead through modification of both the biaryl and heteroaryl components has resulted in the discovery of 6-(4-fluorophenyl)-2-methyl-N-(2-methylbenzothiazol-5-yl)nicotinamide (32; SB-782443) which possesses an excellent overall profile and has been progressed into pre-clinical development.
Asunto(s)
Benzotiazoles/síntesis química , Química Farmacéutica/métodos , Niacinamida/análogos & derivados , Niacinamida/síntesis química , Canales Catiónicos TRPV/antagonistas & inhibidores , Canales Catiónicos TRPV/química , Administración Oral , Animales , Benzotiazoles/farmacología , Capsaicina/química , Línea Celular , Diseño de Fármacos , Cobayas , Humanos , Inflamación , Concentración 50 Inhibidora , Modelos Químicos , Niacinamida/química , Niacinamida/farmacología , RatasRESUMEN
We report here the discovery of a class of MCH R1 ligands based on a biphenyl carboxamide template. A docked-in model is presented indicating key interactions in the putative binding site of the receptor. Parallel high throughput synthetic techniques were utilised to allow rapid exploration of the structure-activity relationship around this template, leading to compound SB-568849 which possessed good receptor affinity and selectivity. This compound proved to be an antagonist with stability in vivo, an acceptable brain-blood ratio and oral bioavailability.
Asunto(s)
Amidas/química , Amidas/farmacología , Compuestos de Bifenilo/síntesis química , Compuestos de Bifenilo/farmacología , Receptores de Somatostatina/antagonistas & inhibidores , Amidas/síntesis química , Amidas/farmacocinética , Animales , Compuestos de Bifenilo/química , Compuestos de Bifenilo/farmacocinética , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Bovinos , Biología Computacional , Humanos , Ligandos , Modelos Moleculares , Estructura Molecular , Receptores de Somatostatina/química , Receptores de Somatostatina/metabolismo , Relación Estructura-Actividad , Azufre/químicaRESUMEN
A strategy of systematically targeting more rigid analogues of the known MCH R1 receptor antagonist, SB-568849, serendipitously uncovered a binding mode accessible to N-aryl-phthalimide ligands. Optimisation to improve the stability of this compound class led to the discovery of novel N-aryl-quinazolinones, benzotriazinones and thienopyrimidinones as selective ligands with good affinity for human melanin-concentrating hormone receptor 1.
Asunto(s)
Amidas/farmacología , Compuestos de Bifenilo/farmacología , Receptores de Somatostatina/antagonistas & inhibidores , Amidas/síntesis química , Amidas/química , Anilidas/química , Compuestos de Bifenilo/síntesis química , Compuestos de Bifenilo/química , Humanos , Estructura Molecular , Receptores de Somatostatina/metabolismo , Relación Estructura-ActividadRESUMEN
Starting from the high throughput screening hit (3), novel N-tetrahydroquinolinyl, N-quinolinyl and N-isoquinolinyl carboxamides have been identified as potent antagonists of the ion channel TRPV1. The N-quinolinylnicotinamide (46) showed excellent potency at human, guinea pig and rat TRPV1, a favourable in vitro DMPK profile and activity in an in vivo model of inflammatory pain.
Asunto(s)
Benzamidas/química , Benzamidas/farmacología , Isoquinolinas/química , Isoquinolinas/farmacología , Quinolinas/química , Quinolinas/farmacología , Canales Catiónicos TRPV/antagonistas & inhibidores , Animales , Benzamidas/síntesis química , Capsaicina/farmacología , Cobayas , Humanos , Isoquinolinas/síntesis química , Hígado/efectos de los fármacos , Hígado/metabolismo , Estructura Molecular , Quinolinas/síntesis química , Ratas , Relación Estructura-Actividad , Canales Catiónicos TRPV/metabolismoRESUMEN
At their clinical doses, current antipsychotic agents share the property of both dopamine D(2) and D(3) receptor blockade. However, a major disadvantage of many current medications are the observed extrapyramidal side-effects (EPS), postulated to arise from D(2) receptor antagonism. Consequently, a selective dopamine D(3) receptor antagonist could offer an attractive antipsychotic therapy, devoid of the unwanted EPS. Using SAR information gained in two previously reported series of potent and selective D(3) receptor antagonists, as exemplified by the 2,3,4,5-tetrahydro-1H-3-benzazepine 10 and the 2,3-dihydro-1H-isoindoline 11, a range of 7-sulfonyloxy- and 7-sulfonylbenzazepines has been prepared. Compounds of this type combined a high level of D(3) affinity and selectivity vs D(2) with an excellent pharmacokinetic profile in the rat. Subsequent optimization of this series to improve selectivity over a range of receptors and reduce cytochrome P450 inhibitory potential gave trans-3-(2-(4-((3-(3-(5-methyl-1,2,4-oxidiazolyl))phenyl)carboxamido)cyclohexyl)ethyl)-7-methylsulfonyl-2,3,4,5-tetrahydro-1H-3-benzazepine (58, SB-414796). This compound is a potent and selective dopamine D(3) receptor antagonist with high oral bioavailability and is CNS penetrant in the rat. Subsequent evaluation in the rat has shown that 58 preferentially reduces firing of dopaminergic cells in the ventral tegmental area (A10) compared to the substantia nigra (A9), an observation consistent with a prediction for atypical antipsychotic efficacy. In a separate study, 58 has been shown to block expression of the conditioned place preference (CPP) response to cocaine in male rats, suggesting that it may also have a role in the treatment of cue-induced relapse in drug-free cocaine addicts.
Asunto(s)
Antipsicóticos/síntesis química , Benzazepinas/síntesis química , Antagonistas de Dopamina/síntesis química , Antagonistas de los Receptores de Dopamina D2 , Sulfonas/síntesis química , Potenciales de Acción/efectos de los fármacos , Administración Oral , Animales , Antipsicóticos/farmacocinética , Antipsicóticos/farmacología , Benzazepinas/farmacocinética , Benzazepinas/farmacología , Disponibilidad Biológica , Células CHO , Catalepsia/inducido químicamente , Cocaína/farmacología , Condicionamiento Clásico/efectos de los fármacos , Cricetinae , Dopamina/metabolismo , Antagonistas de Dopamina/farmacocinética , Antagonistas de Dopamina/farmacología , Diseño de Fármacos , Humanos , Masculino , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/fisiología , Prolactina/sangre , Ensayo de Unión Radioligante , Ratas , Ratas Sprague-Dawley , Receptores de Dopamina D3 , Relación Estructura-Actividad , Sustancia Negra/citología , Sustancia Negra/efectos de los fármacos , Sustancia Negra/fisiología , Sulfonas/farmacocinética , Sulfonas/farmacología , Área Tegmental Ventral/citología , Área Tegmental Ventral/efectos de los fármacos , Área Tegmental Ventral/fisiologíaRESUMEN
Apelin peptides have recently been identified to be the endogenous ligands for the G protein-coupled receptor APJ. However, little is known about the physiological roles of this ligand-receptor pairing. In the present study we investigated the pharmacology of several apelin analogues at the human recombinant APJ receptor using radioligand binding and functional assays. This has led to the identification of key residues in the apelin peptide required for functional potency and binding affinity through structure-activity studies. In particular, we have identified that replacement of leucine in position 5, or arginine in position 2 and 4 of the C-terminal apelin peptide, apelin-13, resulted in significant changes in pharmacology. We also investigated the detailed localization of pre-proapelin and APJ receptor mRNA in a wide range of human, rat and mouse tissues using quantitative RT-PCR, and carried out a detailed immunohistochemical study of the distribution of the APJ receptor in rat brain and spinal cord. Interestingly, the APJ receptor was not only co-localized in white matter with GFAP in the spinal cord, but was also clearly localized on neurones in the brain, suggesting that this receptor and its peptide may be involved in a wide range of biological process yet to be determined.