RESUMEN
The design of potent Pin1 inhibitors has been challenging because its active site specifically recognizes a phospho-protein epitope. The de novo design of phosphate-based Pin1 inhibitors focusing on the phosphate recognition pocket and the successful replacement of the phosphate group with a carboxylate have been previously reported. The potency of the carboxylate series is now further improved through structure-based optimization of ligand-protein interactions in the proline binding site which exploits the H-bond interactions necessary for Pin1 catalytic function. Further optimization using a focused library approach led to the discovery of low nanomolar non-phosphate small molecular Pin1 inhibitors. Structural modifications designed to improve cell permeability resulted in Pin1 inhibitors with low micromolar anti-proliferative activities against cancer cells.
Asunto(s)
Bencimidazoles/farmacología , Ácidos Carboxílicos/farmacología , Inhibidores Enzimáticos/farmacología , Isomerasa de Peptidilprolil/antagonistas & inhibidores , Fosfatos/química , Bencimidazoles/síntesis química , Bencimidazoles/química , Ácidos Carboxílicos/síntesis química , Ácidos Carboxílicos/química , Dominio Catalítico/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Humanos , Estructura Molecular , Peptidilprolil Isomerasa de Interacción con NIMA , Isomerasa de Peptidilprolil/metabolismo , Relación Estructura-ActividadRESUMEN
The M2 isoform of pyruvate kinase is an emerging target for antitumor therapy. In this letter, we describe the discovery of 2-((1H-benzo[d]imidazol-1-yl)methyl)-4H-pyrido[1,2-a]pyrimidin-4-ones as potent and selective PKM2 activators which were found to have a novel binding mode. The original lead identified from high throughput screening was optimized into an efficient series via computer-aided structure-based drug design. Both a representative compound from this series and an activator described in the literature were used as molecular tools to probe the biological effects of PKM2 activation on cancer cells. Our results suggested that PKM2 activation alone is not sufficient to alter cancer cell metabolism.
Asunto(s)
Bencimidazoles/química , Proteínas Portadoras/agonistas , Proteínas de la Membrana/agonistas , Pirimidinonas/química , Hormonas Tiroideas/agonistas , Sitios de Unión , Proteínas Portadoras/metabolismo , Línea Celular , Diseño Asistido por Computadora , Evaluación Preclínica de Medicamentos , Ensayos Analíticos de Alto Rendimiento , Humanos , Cinética , Proteínas de la Membrana/metabolismo , Simulación del Acoplamiento Molecular , Unión Proteica , Estructura Terciaria de Proteína , Pirimidinonas/síntesis química , Pirimidinonas/metabolismo , Relación Estructura-Actividad , Hormonas Tiroideas/metabolismo , Proteínas de Unión a Hormona TiroideRESUMEN
Despite abundant evidence that aberrant Rho-family GTPase activation contributes to most steps of cancer initiation and progression, there is a dearth of inhibitors of their effectors (e.g., p21-activated kinases). Through high-throughput screening and structure-based design, we identify PF-3758309, a potent (K(d) = 2.7 nM), ATP-competitive, pyrrolopyrazole inhibitor of PAK4. In cells, PF-3758309 inhibits phosphorylation of the PAK4 substrate GEF-H1 (IC(50) = 1.3 nM) and anchorage-independent growth of a panel of tumor cell lines (IC(50) = 4.7 +/- 3 nM). The molecular underpinnings of PF-3758309 biological effects were characterized using an integration of traditional and emerging technologies. Crystallographic characterization of the PF-3758309/PAK4 complex defined determinants of potency and kinase selectivity. Global high-content cellular analysis confirms that PF-3758309 modulates known PAK4-dependent signaling nodes and identifies unexpected links to additional pathways (e.g., p53). In tumor models, PF-3758309 inhibits PAK4-dependent pathways in proteomic studies and regulates functional activities related to cell proliferation and survival. PF-3758309 blocks the growth of multiple human tumor xenografts, with a plasma EC(50) value of 0.4 nM in the most sensitive model. This study defines PAK4-related pathways, provides additional support for PAK4 as a therapeutic target with a unique combination of functions (apoptotic, cytoskeletal, cell-cycle), and identifies a potent, orally available small-molecule PAK inhibitor with significant promise for the treatment of human cancers.
Asunto(s)
Proliferación Celular/efectos de los fármacos , Modelos Moleculares , Neoplasias/metabolismo , Pirazoles/farmacología , Pirroles/farmacología , Transducción de Señal/efectos de los fármacos , Quinasas p21 Activadas/antagonistas & inhibidores , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cristalografía , Factores de Intercambio de Guanina Nucleótido/metabolismo , Humanos , Neoplasias/tratamiento farmacológico , Fosforilación/efectos de los fármacos , Pirazoles/química , Pirazoles/metabolismo , Pirroles/química , Pirroles/metabolismo , Factores de Intercambio de Guanina Nucleótido RhoRESUMEN
Oxobenzimidazoles (e.g., 1), a novel series of androgen receptor (AR) antagonists, were discovered through de novo design guided by structure-based drug design. The compounds in this series were reasonably permeable and metabolically stable, but suffered from poor solubility. The incorporation of three dimensional structural features led to improved solubility. In addition, the observation of a 'flipped' binding mode of an oxobenzimidazole analog in an AR ligand binding domain (LBD) model, led to the design and discovery of the novel oxindole series (e.g., 2) that is a potent full antagonist of AR.
Asunto(s)
Antagonistas de Receptores Androgénicos/síntesis química , Antineoplásicos/síntesis química , Bencimidazoles/síntesis química , Indoles/síntesis química , Receptores Androgénicos/química , Antagonistas de Receptores Androgénicos/farmacología , Antineoplásicos/farmacología , Bencimidazoles/farmacología , Línea Celular Tumoral , Diseño de Fármacos , Descubrimiento de Drogas , Humanos , Indoles/farmacología , Ligandos , Masculino , Modelos Moleculares , Neoplasias de la Próstata , Unión Proteica , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Receptores Androgénicos/metabolismo , Solubilidad , Relación Estructura-ActividadRESUMEN
(S)-1-((4-(3-(6-Amino-5-methoxypyridin-3-yl)-1-isopropyl-1H-pyrazol-4-yl)pyrimidin-2-yl)amino)propan-2-ol, 1, was recently identified as a potent inhibitor of the oncogenic kinase bRAF. Compounds containing 3-methoxy-2-aminopyridine, as in 1, comprised a promising lead series because of their high ligand efficiency and excellent ADME profile. However, following metabolic oxidation, compounds in this series also demonstrated two significant safety risks: mutagenic potential and time-dependent drug-drug interaction (TDI). Metabolite identification studies revealed formation of a reactive metabolite. We hypothesized that minimizing or blocking the formation of such a metabolite would mitigate the safety liabilities. Our investigation demonstrated that structural modifications which either reduced the electron density of the 3-methoxy-2-aminopyridine ring or blocked the reactive site following metabolic oxidation were successful in reducing TDI and AMES mutagenicity.
Asunto(s)
Aminopiridinas/química , Aminopiridinas/metabolismo , Electrones , Humanos , Microsomas Hepáticos/química , Microsomas Hepáticos/metabolismo , Estructura Molecular , Pruebas de Mutagenicidad , Oxidación-Reducción , Factores de TiempoRESUMEN
High throughput cell-based screening led to the identification of 3-aryloxy lactams as potent androgen receptor (AR) antagonists. Refinement of these leads to improve the ADME profile and remove residual agonism led to the discovery of 12, a potent full antagonist with greater oral bioavailability. Improvements in the ADME profile were realized by designing more ligand-efficient molecules with reduced molecular weights and lower lipophilicities.
Asunto(s)
Descubrimiento de Drogas , Lactamas/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Receptores Androgénicos/química , Relación Dosis-Respuesta a Droga , Ensayos Analíticos de Alto Rendimiento , Humanos , Lactamas/síntesis química , Lactamas/química , Masculino , Modelos Moleculares , Estructura Molecular , Neoplasias de la Próstata/cirugía , Receptores Androgénicos/metabolismo , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
Following the discovery of a novel series of phosphate-containing small molecular Pin1 inhibitors, the drug design strategy shifted to replacement of the phosphate group with an isostere with potential better pharmaceutical properties. The initial loss in potency of carboxylate analogs was likely due to weaker charge-charge interactions in the putative phosphate binding pocket and was subsequently recovered by structure-based optimization of ligand-protein interactions in the proline binding site, leading to the discovery of a sub-micromolar non-phosphate small molecular Pin1 inhibitor.
Asunto(s)
Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Isomerasa de Peptidilprolil/antagonistas & inhibidores , Isomerasa de Peptidilprolil/metabolismo , Sitios de Unión , Cristalografía por Rayos X , Diseño de Fármacos , Humanos , Modelos Moleculares , Peptidilprolil Isomerasa de Interacción con NIMA , Isomerasa de Peptidilprolil/química , Unión Proteica , Relación Estructura-ActividadRESUMEN
Pin1 is a member of the cis-trans peptidyl-prolyl isomerase family with potential anti-cancer therapeutic value. Here we report structure-based de novo design and optimization of novel Pin1 inhibitors. Without a viable lead from internal screenings, we designed a series of novel Pin1 inhibitors by interrogating and exploring a protein crystal structure of Pin1. The ligand efficiency of the initial concept molecule was optimized with integrated SBDD and parallel chemistry approaches, resulting in a more attractive lead series.
Asunto(s)
Inhibidores Enzimáticos/química , Isomerasa de Peptidilprolil/antagonistas & inhibidores , Secuencia de Aminoácidos , Sitios de Unión , Técnicas Químicas Combinatorias , Simulación por Computador , Cristalografía por Rayos X , Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Humanos , Peptidilprolil Isomerasa de Interacción con NIMA , Isomerasa de Peptidilprolil/metabolismo , Relación Estructura-ActividadRESUMEN
Since the discovery that FK-506 promotes neurite outgrowth, considerable attention has been focused on the development of potent nonimmunosuppressive ligands for FK-506 binding proteins (FKBPs). Such neuroimmunophilin agents have been reported to show neuroregenerative activity in a variety of cell and animal models including neurite outgrowth, age-related cognitive decline, Parkinson's disease, peripheral nerve injury, optic nerve degeneration, and diabetic neuropathy. We have designed and synthesized a unique series of tetracyclic aza-amides that have been shown to be potent FKBP12 rotamase inhibitors. The structure-activity relationships established in this study have demonstrated diverse structural modifications that result in potent rotamase inhibitory activity.
Asunto(s)
Amidas/síntesis química , Compuestos Aza/síntesis química , Compuestos Heterocíclicos de 4 o más Anillos/síntesis química , Fármacos Neuroprotectores/síntesis química , Proteína 1A de Unión a Tacrolimus/antagonistas & inhibidores , Proteína 1A de Unión a Tacrolimus/química , Amidas/química , Compuestos Aza/química , Sitios de Unión , Compuestos Heterocíclicos de 4 o más Anillos/química , Enlace de Hidrógeno , Isoquinolinas/síntesis química , Isoquinolinas/química , Ligandos , Fármacos Neuroprotectores/química , Relación Estructura-Actividad , Tacrolimus/químicaRESUMEN
[reaction: see text] Treatment of 1,4-dilithio-1,3-butadiyne (1) with dichalcogenides RSSR or RSeSeR affords dithio- and diseleno-1,3-butadiynes (2, 3), perthio- and perseleno-[3]-cumulenes (4, 5), perthio- and perseleno-1,3-butadienes (6, 7), and/or perthio- and perseleno-but-1-ene-3-ynes (8, 9). The products can be controlled by stoichiometry and temperature, by the presence or absence of oxygen, and by choice of the "R" group. By X-ray crystallography, hexa(methylthio)-1,3-butadiene is highly twisted, with a torsion angle [Phi(CCCC)] of 84.7 degrees and an elongated C(2)-C(3) distance of 1.484(3) A.
RESUMEN
The P21-activated kinases (PAK) are emerging antitumor therapeutic targets. In this paper, we describe the discovery of potent PAK inhibitors guided by structure-based drug design. In addition, the efflux of the pyrrolopyrazole series was effectively reduced by applying multiple medicinal chemistry strategies, leading to a series of PAK inhibitors that are orally active in inhibiting tumor growth in vivo.
Asunto(s)
Antineoplásicos/síntesis química , Pirazoles/síntesis química , Pirroles/síntesis química , Quinasas p21 Activadas/antagonistas & inhibidores , Administración Oral , Amidas/síntesis química , Amidas/farmacocinética , Amidas/farmacología , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Carbamatos/química , Carbamatos/farmacocinética , Carbamatos/farmacología , Cristalografía por Rayos X , Perros , Humanos , Enlace de Hidrógeno , Ratones , Modelos Moleculares , Conformación Molecular , Permeabilidad , Pirazoles/farmacocinética , Pirazoles/farmacología , Pirroles/farmacocinética , Pirroles/farmacología , Ratas , Estereoisomerismo , Relación Estructura-Actividad , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
N-{trans-3-[(5-Cyano-6-methylpyridin-2-yl)oxy]-2,2,4,4-tetramethylcyclobutyl}imidazo[1,2-a]pyrimidine-3-carboxamide (1) was recently identified as a full antagonist of the androgen receptor, demonstrating excellent in vivo tumor growth inhibition in castration-resistant prostate cancer (CRPC). However, the imidazo[1,2-a]pyrimidine moiety is rapidly metabolized by aldehyde oxidase (AO). The present paper describes a number of medicinal chemistry strategies taken to avoid the AO-mediated oxidation of this particular system. Guided by an AO protein structure-based model, our investigation revealed the most probable site of AO oxidation and the observation that altering the heterocycle or blocking the reactive site are two of the more effective strategies for reducing AO metabolism. These strategies may be useful for other drug discovery programs.
Asunto(s)
Aldehído Oxidasa/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Ciclobutanos/química , Imidazoles/química , Pirimidinas/química , Aldehído Oxidasa/metabolismo , Dominio Catalítico , Humanos , Imidazoles/síntesis química , Imidazoles/metabolismo , Modelos Moleculares , Oxidación-Reducción , Unión Proteica , Pirimidinas/síntesis química , Pirimidinas/metabolismo , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
An aryloxy tetramethylcyclobutane was identified as a novel template for androgen receptor (AR) antagonists via cell-based high-throughput screening. Follow-up to the initial "hit" established 5 as a viable lead. Further optimization to achieve full AR antagonism led to the discovery of 26 and 30, both of which demonstrated excellent in vivo tumor growth inhibition upon oral administration in a castration-resistant prostate cancer (CRPC) animal model.