RESUMEN
Preventing histone recognition by bromodomains emerges as an attractive therapeutic approach in cancer. Overexpression of ATAD2 (ATPase family AAA domain-containing 2 isoform A) in cancer cells is associated with poor prognosis making the bromodomain of ATAD2 a promising epigenetic therapeutic target. In the development of an in vitro assay and identification of small molecule ligands, we conducted structure-guided studies which revealed a conformationally flexible ATAD2 bromodomain. Structural studies on apo-, peptide-and small molecule-ATAD2 complexes (by co-crystallization) revealed that the bromodomain adopts a 'closed', histone-compatible conformation and a more 'open' ligand-compatible conformation of the binding site respectively. An unexpected conformational change of the conserved asparagine residue plays an important role in driving the peptide-binding conformation remodelling. We also identified dimethylisoxazole-containing ligands as ATAD2 binders which aided in the validation of the in vitro screen and in the analysis of these conformational studies.
Asunto(s)
Adenosina Trifosfatasas/química , Proteínas de Unión al ADN/química , Diseño de Fármacos , Inhibidores Enzimáticos/química , Histonas/química , Isoxazoles/química , Fragmentos de Péptidos/química , Procesamiento Proteico-Postraduccional , ATPasas Asociadas con Actividades Celulares Diversas , Adenosina Trifosfatasas/antagonistas & inhibidores , Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Sitios de Unión , Biotinilación , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Histonas/antagonistas & inhibidores , Histonas/metabolismo , Humanos , Isoxazoles/síntesis química , Isoxazoles/farmacología , Cinética , Ligandos , Proteínas Mutantes/antagonistas & inhibidores , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Fragmentos de Péptidos/antagonistas & inhibidores , Fragmentos de Péptidos/metabolismo , Docilidad , Conformación Proteica , Dominios y Motivos de Interacción de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Sulfonamidas/síntesis química , Sulfonamidas/química , Sulfonamidas/farmacología , metaminobenzoatos/síntesis química , metaminobenzoatos/química , metaminobenzoatos/farmacologíaRESUMEN
Two classes of ACK1 inhibitors, 4,5,6-trisubstituted furo[2,3-d]pyrimidin4-amines and 4,5,6-trisubstituted 7H-pyrrolo[2,3-d]pyrimidin-4-amines, were discovered and evaluated as ACK1 inhibitors. Further structural refinement led to the identification of potent and selective dithiolane inhibitor 37.
Asunto(s)
Furanos/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Pirimidinas/farmacología , Pirroles/farmacología , Relación Dosis-Respuesta a Droga , Furanos/síntesis química , Furanos/química , Humanos , Modelos Moleculares , Estructura Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proteínas Tirosina Quinasas/metabolismo , Pirimidinas/síntesis química , Pirimidinas/química , Pirroles/síntesis química , Pirroles/química , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
A new series of pyrazolo[3,4-d]pyrimidine-3,6-diamines was designed and synthesized as potent and selective inhibitors of the nonreceptor tyrosine kinase, ACK1. These compounds arose from efforts to rigidify an earlier series of N-aryl pyrimidine-5-carboxamides. The synthesis and structure-activity relationships of this new series of inhibitors are reported. The most promising compounds were also profiled for their pharmacokinetic properties.
Asunto(s)
Diaminas/antagonistas & inhibidores , Inhibidores Enzimáticos/síntesis química , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Pirazoles/química , Pirimidinas/química , Animales , Química Farmacéutica/métodos , Cristalografía por Rayos X/métodos , Diseño de Fármacos , Inhibidores Enzimáticos/farmacología , Concentración 50 Inhibidora , Masculino , Modelos Químicos , Conformación Molecular , Proteínas Tirosina Quinasas/química , Ratas , Ratas Sprague-Dawley , Relación Estructura-ActividadRESUMEN
An imidazo[4,5-h]isoquinolin-7,9-dione (1) was identified as an adenosine 5'-triphosphate competitive inhibitor of lck by high throughput screening. Initial structure-activity relationship studies identified the dichlorophenyl ring and the imide NH as important pharmacophores. A binding model was constructed to understand how 1 binds to a related kinase, hck. These results suggested that removing the gem-dimethyl group and flattening the ring would enhance activity. This was realized by converting 1 to the imidazo[4,5-h]isoquinolin-9-one (20), resulting in an 18-fold improvement in potency against lck and a 50-fold increase in potency in a cellular assay.
Asunto(s)
Inhibidores Enzimáticos/síntesis química , Imidazoles/síntesis química , Isoquinolinas/síntesis química , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/antagonistas & inhibidores , Animales , Anticuerpos/farmacología , Sitios de Unión , Complejo CD3/inmunología , Cristalografía por Rayos X , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Femenino , Humanos , Imidazoles/química , Imidazoles/farmacología , Interleucina-2/biosíntesis , Isoquinolinas/química , Isoquinolinas/farmacología , Células Jurkat , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Conformación Molecular , Relación Estructura-Actividad , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismoRESUMEN
The tyrosine kinase p56lck (lck) is essential for T cell activation; thus, inhibitors of lck have potential utility as autoimmune agents. Our initial disclosure of a new class of lck inhibitors based on the phenylaminoimidazoisoquinolin-9-one showed reasonable cellular activity but did not work in vivo upon oral administration. Our current work highlights the further use of rational drug design and molecular modeling to produce a series of lck inhibitors that demonstrate cellular activity below 100 nM and are as efficacious as cyclosporin A in an in vivo mouse model of anti-CD3-induced IL-2 production.
Asunto(s)
Bencimidazoles/síntesis química , Inhibidores Enzimáticos/síntesis química , Inmunosupresores/síntesis química , Isoquinolinas/síntesis química , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/antagonistas & inhibidores , Administración Oral , Animales , Anticuerpos Monoclonales/farmacología , Bencimidazoles/química , Bencimidazoles/farmacología , Complejo CD3/inmunología , Cristalografía por Rayos X , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Femenino , Humanos , Inmunosupresores/química , Inmunosupresores/farmacología , Interleucina-2/antagonistas & inhibidores , Interleucina-2/biosíntesis , Interleucina-2/sangre , Isoquinolinas/química , Isoquinolinas/farmacología , Células Jurkat , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Conformación Molecular , Unión Proteica , Relación Estructura-ActividadRESUMEN
An uHTS campaign was performed to identify selective inhibitors of PKC-theta. Initial triaging of the hit set based on selectivity and historical analysis led to the identification of 2,4-diamino-5-nitropyrimidines as potent and selective PKC-theta inhibitors. A homology model and initial SAR is presented demonstrating that a 2-arylalkylamino substituent in conjunction with suitable 4-diamino substituent are essential for achieving selectivity over many kinases. Additional hit to lead profiling is presented on selected compounds.