RESUMEN
Ubiquitination controls the stability of most cellular proteins, and its deregulation contributes to human diseases including cancer. Deubiquitinases remove ubiquitin from proteins, and their inhibition can induce the degradation of selected proteins, potentially including otherwise 'undruggable' targets. For example, the inhibition of ubiquitin-specific protease 7 (USP7) results in the degradation of the oncogenic E3 ligase MDM2, and leads to re-activation of the tumour suppressor p53 in various cancers. Here we report that two compounds, FT671 and FT827, inhibit USP7 with high affinity and specificity in vitro and within human cells. Co-crystal structures reveal that both compounds target a dynamic pocket near the catalytic centre of the auto-inhibited apo form of USP7, which differs from other USP deubiquitinases. Consistent with USP7 target engagement in cells, FT671 destabilizes USP7 substrates including MDM2, increases levels of p53, and results in the transcription of p53 target genes, induction of the tumour suppressor p21, and inhibition of tumour growth in mice.
Asunto(s)
Piperidinas/farmacología , Pirazoles/farmacología , Pirimidinas/farmacología , Peptidasa Específica de Ubiquitina 7/antagonistas & inhibidores , Animales , Apoenzimas/antagonistas & inhibidores , Apoenzimas/química , Apoenzimas/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cristalografía por Rayos X , Femenino , Humanos , Ratones , Modelos Moleculares , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Neoplasias/patología , Piperidinas/síntesis química , Proteínas Proto-Oncogénicas c-mdm2/química , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Pirazoles/síntesis química , Pirimidinas/síntesis química , Especificidad por Sustrato , Transcripción Genética/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Peptidasa Específica de Ubiquitina 7/química , Peptidasa Específica de Ubiquitina 7/metabolismo , Ubiquitinación/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Reversible janus associated kinase (JAK) inhibitors such as tofacitinib and decernotinib block cytokine signaling and are efficacious in treating autoimmune diseases. However, therapeutic doses are limited due to inhibition of other JAK/signal transducer and activator of transcription pathways associated with hematopoiesis, lipid biogenesis, infection, and immune responses. A selective JAK3 inhibitor may have a better therapeutic index; however, until recently, no compounds have been described that maintain JAK3 selectivity in cells, as well as against the kinome, with good physicochemical properties to test the JAK3 hypothesis in vivo. To quantify the biochemical basis for JAK isozyme selectivity, we determined that the apparent Km value for each JAK isozyme ranged from 31.8 to 2.9 µM for JAK1 and JAK3, respectively. To confirm compound activity in cells, we developed a novel enzyme complementation assay that read activity of single JAK isozymes in a cellular context. Reversible JAK3 inhibitors cannot achieve sufficient selectivity against other isozymes in the cellular context due to inherent differences in enzyme ATP Km values. Therefore, we developed irreversible JAK3 compounds that are potent and highly selective in vitro in cells and against the kinome. Compound 2, a potent inhibitor of JAK3 (0.15 nM) was 4300-fold selective for JAK3 over JAK1 in enzyme assays, 67-fold [interleukin (IL)-2 versus IL-6] or 140-fold [IL-2 versus erythropoietin or granulocyte-macrophage colony-stimulating factor (GMCSF)] selective in cellular reporter assays and >35-fold selective in human peripheral blood mononuclear cell assays (IL-7 versus IL-6 or GMCSF). In vivo, selective JAK3 inhibition was sufficient to block the development of inflammation in a rat model of rheumatoid arthritis, while sparing hematopoiesis.
Asunto(s)
Enfermedades Autoinmunes , Janus Quinasa 1 , Janus Quinasa 3 , Piperidinas/farmacología , Pirimidinas/farmacología , Pirroles/farmacología , Animales , Artritis Experimental/tratamiento farmacológico , Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/metabolismo , Relación Dosis-Respuesta a Droga , Monitoreo de Drogas/métodos , Humanos , Isoenzimas , Janus Quinasa 1/antagonistas & inhibidores , Janus Quinasa 1/química , Janus Quinasa 1/metabolismo , Janus Quinasa 3/antagonistas & inhibidores , Janus Quinasa 3/química , Janus Quinasa 3/metabolismo , Monitorización Inmunológica/métodos , Inhibidores de Proteínas Quinasas/farmacología , RatasRESUMEN
Selective inhibition of Kv1.5, which underlies the ultra-rapid delayed rectifier current, IKur, has been pursued as a treatment for atrial fibrillation. Here we describe the discovery of MK-1832, a Kv1.5 inhibitor with improved selectivity versus the off-target current IKs, whose inhibition has been associated with ventricular proarrhythmia. MK-1832 exhibits improved selectivity for IKur over IKs (>3000-fold versus 70-fold for MK-0448), consistent with an observed larger window between atrial and ventricular effects in vivo (>1800-fold versus 210-fold for MK-0448). MK-1832 also exhibits an improved preclinical pharmacokinetic profile consistent with projected once daily dosing in humans.
Asunto(s)
Canal de Potasio Kv1.5/antagonistas & inhibidores , Piridinas/farmacología , Descubrimiento de Drogas , Humanos , Piridinas/farmacocinética , Relación Estructura-ActividadRESUMEN
The mammalian Janus Kinases (JAK1, JAK2, JAK3 and TYK2) are intracellular, non-receptor tyrosine kinases whose activities have been associated in the literature and the clinic with a variety of hyperproliferative diseases and immunological disorders. At the onset of the program, it was hypothesized that a JAK1 selective compound over JAK2 could lead to an improved therapeutic index relative to marketed non-selective JAK inhibitors by avoiding the clinical AEs, such as anemia, presumably associated with JAK2 inhibition. During the course of the JAK1 program, a number of diverse chemical scaffolds were identified from both uHTS campaigns and de novo scaffold design. As part of this effort, a (benz)imidazole scaffold evolved via a scaffold-hopping exercise from a mature chemical series. Concurrent crystallography-driven exploration of the ribose pocket and the solvent front led to analogs with optimized kinome and JAK1 selectivities over the JAK2 isoform by targeting several residues unique to JAK1, such as Arg-879 and Glu-966.
Asunto(s)
Bencimidazoles/química , Bencimidazoles/farmacología , Janus Quinasa 1/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Piridonas/química , Piridonas/farmacología , Bencimidazoles/síntesis química , Cristalografía por Rayos X , Diseño de Fármacos , Humanos , Janus Quinasa 1/metabolismo , Modelos Moleculares , Inhibidores de Proteínas Quinasas/síntesis química , Piridonas/síntesis química , Relación Estructura-ActividadRESUMEN
This communication discusses the discovery of novel reverse tricyclic pyridones as inhibitors of Janus kinase 2 (JAK2). By using a kinase cross screening approach coupled with molecular modeling, a unique inhibitor-water interaction was discovered to impart excellent broad kinase selectivity. Improvements in intrinsic potency were achieved by utilizing a rapid library approach, while targeted structural changes to lower lipophilicity led to improved rat pharmacokinetics. This multi-pronged approach led to the identification of 31, which demonstrated encouraging rat pharmacokinetics, in vivo potency, and excellent off-target kinase selectivity.
Asunto(s)
Janus Quinasa 2/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/química , Piridonas/química , Sulfonamidas/química , Adenosina Trifosfato/química , Adenosina Trifosfato/metabolismo , Animales , Sitios de Unión , Evaluación Preclínica de Medicamentos , Semivida , Janus Quinasa 2/metabolismo , Simulación de Dinámica Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacocinética , Estructura Terciaria de Proteína , Piridonas/síntesis química , Piridonas/farmacocinética , Ratas , Relación Estructura-Actividad , Sulfonamidas/síntesis química , Sulfonamidas/farmacocinéticaRESUMEN
When a ribosome stalls during translation, it runs the risk of collision with a trailing ribosome. Such an encounter leads to the formation of a stable di-ribosome complex, which needs to be resolved by a dedicated machinery. The initial stalling and the subsequent resolution of di-ribosomal complexes requires activity of Makorin and ZNF598 ubiquitin E3 ligases, respectively, through ubiquitylation of the eS10 and uS10 subunits of the ribosome. We have developed a specific small-molecule inhibitor of the deubiquitylase USP9X. Proteomics analysis, following inhibitor treatment of HCT116 cells, confirms previous reports linking USP9X with centrosome-associated protein stability but also reveals a loss of Makorin 2 and ZNF598. We show that USP9X interacts with both these ubiquitin E3 ligases, regulating their abundance through the control of protein stability. In the absence of USP9X or following chemical inhibition of its catalytic activity, levels of Makorins and ZNF598 are diminished, and the ribosomal quality control pathway is impaired.
Asunto(s)
Ribosomas/metabolismo , Ubiquitina Tiolesterasa/metabolismo , Ubiquitinación , Anticuerpos/metabolismo , Biocatálisis , Proteínas Portadoras/metabolismo , Línea Celular Tumoral , Células HEK293 , Humanos , Estabilidad Proteica , Reproducibilidad de los Resultados , Ribonucleoproteínas/metabolismo , Ubiquitina Tiolesterasa/antagonistas & inhibidoresRESUMEN
Lung squamous cell carcinoma (LSCC) is a considerable global health burden, with an incidence of over 600,000 cases per year. Treatment options are limited, and patient's 5-year survival rate is less than 5%. The ubiquitin-specific protease 28 (USP28) has been implicated in tumourigenesis through its stabilization of the oncoproteins c-MYC, c-JUN, and Δp63. Here, we show that genetic inactivation of Usp28-induced regression of established murine LSCC lung tumours. We developed a small molecule that inhibits USP28 activity in the low nanomole range. While displaying cross-reactivity against the closest homologue USP25, this inhibitor showed a high degree of selectivity over other deubiquitinases. USP28 inhibitor treatment resulted in a dramatic decrease in c-MYC, c-JUN, and Δp63 proteins levels and consequently induced substantial regression of autochthonous murine LSCC tumours and human LSCC xenografts, thereby phenocopying the effect observed by genetic deletion. Thus, USP28 may represent a promising therapeutic target for the treatment of squamous cell lung carcinoma.
Asunto(s)
Proteínas de Unión al ADN/genética , Eliminación de Gen , Neoplasias Pulmonares/genética , Neoplasias de Células Escamosas/genética , Factores de Transcripción/genética , Ubiquitina Tiolesterasa/genética , Animales , Proteínas de Unión al ADN/metabolismo , Modelos Animales de Enfermedad , Humanos , Ratones , Factores de Transcripción/metabolismo , Ubiquitina Tiolesterasa/metabolismoRESUMEN
This paper describes the discovery and design of a novel class of JAK2 inhibitors. Furthermore, we detail the optimization of a screening hit using ligand binding efficiency and log D. These efforts led to the identification of compound 41, which demonstrates in vivo activity in our study.
Asunto(s)
Compuestos Heterocíclicos con 3 Anillos/química , Janus Quinasa 2/antagonistas & inhibidores , Piridonas/química , Animales , Sitios de Unión , Simulación por Computador , Ciclización , Evaluación Preclínica de Medicamentos , Compuestos Heterocíclicos con 3 Anillos/síntesis química , Compuestos Heterocíclicos con 3 Anillos/farmacología , Janus Quinasa 2/metabolismo , Ratones , Ratones Endogámicos C57BL , Piridonas/síntesis química , Piridonas/farmacología , Factor de Transcripción STAT5/metabolismo , Relación Estructura-ActividadRESUMEN
A series of triarylethanolamine inhibitors of the Kv1.5 potassium channel have been prepared and evaluated for their effects in vitro and in vivo. The structure-activity relationship (SAR) studies described herein led to the development of potent, selective and orally active inhibitors of Kv1.5.
Asunto(s)
Etanolaminas/farmacología , Bloqueadores de los Canales de Potasio/farmacología , Canales de Potasio con Entrada de Voltaje/antagonistas & inhibidores , Animales , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos , Etanolaminas/química , Humanos , Bloqueadores de los Canales de Potasio/química , Relación Estructura-ActividadRESUMEN
Inhibition of mutant IDH1 is being evaluated clinically as a treatment option for oncology. Here we describe the structure-based design and optimization of quinoline lead compounds to identify FT-2102, a potent, orally bioavailable, brain penetrant, and selective mIDH1 inhibitor. FT-2102 has excellent ADME/PK properties and reduces 2-hydroxyglutarate levels in an mIDH1 xenograft tumor model. This compound has been selected as a candidate for clinical development in hematologic malignancies, solid tumors, and gliomas with mIDH1.
Asunto(s)
Antineoplásicos/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Isocitrato Deshidrogenasa/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Piridinas/uso terapéutico , Quinolinas/uso terapéutico , Quinolonas/uso terapéutico , Animales , Antineoplásicos/síntesis química , Antineoplásicos/metabolismo , Línea Celular Tumoral , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/metabolismo , Femenino , Humanos , Isocitrato Deshidrogenasa/metabolismo , Ratones Endogámicos BALB C , Estructura Molecular , Unión Proteica , Piridinas/síntesis química , Piridinas/metabolismo , Quinolinas/síntesis química , Quinolinas/metabolismo , Quinolonas/síntesis química , Quinolonas/metabolismo , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
A bench-stable potassium trifluoroborate enol ether reagent has been prepared. This reagent is suitable for the incorporation of 2,2-difluoroenolethers into aryl and heteroaryl systems via palladium-mediated cross-coupling with suitable halide coupling partners.
Asunto(s)
Boratos/química , Éteres/síntesis química , Cetonas/síntesis química , Paladio/química , Éteres/química , Cetonas/química , Estructura Molecular , Sales (Química)/química , EstereoisomerismoRESUMEN
Mutations at the arginine residue (R132) in isocitrate dehydrogenase 1 (IDH1) are frequently identified in various human cancers. Inhibition of mutant IDH1 (mIDH1) with small molecules has been clinically validated as a promising therapeutic treatment for acute myeloid leukemia and multiple solid tumors. Herein, we report the discovery and optimization of a series of quinolinones to provide potent and orally bioavailable mIDH1 inhibitors with selectivity over wild-type IDH1. The X-ray structure of an early lead 24 in complex with mIDH1-R132H shows that the inhibitor unexpectedly binds to an allosteric site. Efforts to improve the in vitro and in vivo absorption, distribution, metabolism, and excretion (ADME) properties of 24 yielded a preclinical candidate 63. The detailed preclinical ADME and pharmacology studies of 63 support further development of quinolinone-based mIDH1 inhibitors as therapeutic agents in human trials.
Asunto(s)
Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Isocitrato Deshidrogenasa/antagonistas & inhibidores , Quinolonas/química , Quinolonas/farmacología , Sitio Alostérico/efectos de los fármacos , Animales , Disponibilidad Biológica , Línea Celular Tumoral , Cristalografía por Rayos X , Perros , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacocinética , Femenino , Humanos , Isocitrato Deshidrogenasa/química , Isocitrato Deshidrogenasa/genética , Células de Riñón Canino Madin Darby , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Mutación Puntual , Quinolonas/farmacocinéticaRESUMEN
Drug discovery efforts have focused recently on atrial-selective targets, including the Kv1.5 channel, which underlies the ultrarapid delayed rectifier current, I(Kur), to develop novel treatments for atrial fibrillation (AF). Two structurally distinct compounds, a triarylethanolamine TAEA and an isoquinolinone 3-[(dimethylamino)-methyl]-6-methoxy-2-methyl-4-phenylisoquinolin-1(2H)-one (ISQ-1), blocked I(Kur) in Chinese hamster ovary cells expressing human Kv1.5 with IC(50) values of 238 and 324 nM, respectively. In anesthetized dogs, i.v. infusions of TAEA and ISQ-1 elicited comparable 16% increases in atrial refractory period, with no effect on ventricular refractory period or QTc interval. Plasma concentrations at end infusion for TAEA and ISQ-1 were 58.5 +/- 23.6 and 330.3 +/- 43.5 nM, respectively. The abilities of TAEA and ISQ-1 to terminate AF, with comparison to the rapidly activating component of delayed rectifier potassium current blocker (+)-N-[1'-(6-cyano-1,2,3,4-tetrahydro-2(R)-naphthalenyl)-3,4-dihydro-4(R)-hydroxyspiro(2H-1-benzopyran-2,4'-piperidin)-6-yl]methanesulfonamide] monohydrochloride (MK-499) and the class IC 1-[2-[2-hydroxy-3-(propylamino)-propoxy]phenyl]-3-phenyl-1-propanone (propafenone), were assessed in conscious dogs with heart failure and inducible AF (entry criterion). All test agents administered in i.v. bolus regimens terminated AF in at least half of animals tested; conversely no agent was universally effective. MK-499, ISQ-1, TAEA, and propafenone terminated AF in five of six, four of seven, four of six, and five of six animals at plasma concentrations of 32.6 +/- 18.7, 817 +/- 274, 714 +/- 622, and 816 +/- 240 nM, respectively. Directed cardiac electrophysiologic studies in anesthetized dogs using i.v. bolus (consistent with AF studies) plus infusion regimens with TAEA and ISQ-1 demonstrated significant increases in atrial refractory period (12-15%), A-H and P-A intervals, but no effects on ventricular refractory period, H-V, and HEG intervals. The demonstration of AF termination with TAEA and ISQ-1 in the dog heart failure model extends the profile of antiarrhythmic efficacy of Kv1.5 blockade.
Asunto(s)
Antiarrítmicos/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Insuficiencia Cardíaca/tratamiento farmacológico , Isoquinolinas/uso terapéutico , Canal de Potasio Kv1.5/antagonistas & inhibidores , Bloqueadores de los Canales de Potasio/uso terapéutico , Piridinas/uso terapéutico , Animales , Fibrilación Atrial/fisiopatología , Benzopiranos/uso terapéutico , Línea Celular , Perros , Femenino , Atrios Cardíacos/efectos de los fármacos , Atrios Cardíacos/fisiopatología , Humanos , Masculino , Piperidinas/uso terapéutico , Propafenona/uso terapéutico , Bloqueadores de los Canales de Sodio/uso terapéuticoRESUMEN
The discovery of a potent selective low dose Janus kinase 1 (JAK1) inhibitor suitable for clinical evaluation is described. As part of an overall goal to minimize dose, we pursued a medicinal chemistry strategy focused on optimization of key parameters that influence dose size, including lowering human Clint and increasing intrinsic potency, bioavailability, and solubility. To impact these multiple parameters simultaneously, we used lipophilic ligand efficiency as a key metric to track changes in the physicochemical properties of our analogs, which led to improvements in overall compound quality. In parallel, structural information guided advancements in JAK1 selectivity by informing on new vector space, which enabled the discovery of a unique key amino acid difference between JAK1 (Glu966) and JAK2 (Asp939). This difference was exploited to consistently produce analogs with the best balance of JAK1 selectivity, efficacy, and projected human dose, ultimately culminating in the discovery of compound 28.
Asunto(s)
Janus Quinasa 1/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Pirazoles/química , Pirazoles/farmacología , Animales , Perros , Descubrimiento de Drogas , Halogenación , Humanos , Janus Quinasa 1/química , Janus Quinasa 1/metabolismo , Simulación del Acoplamiento Molecular , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacocinética , Pirazoles/administración & dosificación , Pirazoles/farmacocinética , Ratas , Relación Estructura-ActividadRESUMEN
Novel 3-cyanoisoquinoline Kv1.5 antagonists have been prepared and evaluated in in vitro and in vivo assays for inhibition of the Kv1.5 potassium channel and its associated cardiac potassium current, IKur. Structural modifications of isoquinolinone lead 1 afforded compounds with excellent potency, selectivity, and oral bioavailability.
Asunto(s)
Antiarrítmicos/síntesis química , Fibrilación Atrial/tratamiento farmacológico , Isoquinolinas/síntesis química , Canal de Potasio Kv1.5/antagonistas & inhibidores , Nitrilos/síntesis química , Administración Oral , Animales , Antiarrítmicos/química , Antiarrítmicos/farmacología , Disponibilidad Biológica , Electrofisiología , Corazón/efectos de los fármacos , Corazón/fisiología , Humanos , Isoquinolinas/química , Isoquinolinas/farmacología , Canal de Potasio Kv1.5/fisiología , Nitrilos/química , Nitrilos/farmacología , Técnicas de Placa-Clamp , Ratas , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
The development of farnesyltransferase inhibitors, a novel approach to non-cytotoxic anticancer therapy, has been an active area of research over the past decade. Compounds that have advanced to clinical trials were evolved both from substrate-based design efforts and from compound library screening hits. This review focuses on the effort at Merck to evolve inhibitors from the protein substrate of farnesyltransferase, which resulted in the identification of a non-peptide inhibitor for clinical evaluation. X-ray crystal structures of farnesyltransferase complexed with early peptidomimetic as well as later non-peptide inhibitors have validated this design approach. NMR spectroscopic methods for studying enzyme-bound inhibitor structure, in conjunction with the use of conformational constraints, were critical components of subsequent efforts to provide potent inhibitors with varying levels of farnesyltransferase and geranylgeranyltransferase-I inhibitory specificity. Several of these compounds were important tools for investigating the use of prenyltransferase inhibitors to target Ki-Ras-mediated tumor growth.
Asunto(s)
Transferasas Alquil y Aril/antagonistas & inhibidores , Antineoplásicos/química , Inhibidores Enzimáticos/química , Neoplasias/tratamiento farmacológico , Animales , Antineoplásicos/farmacología , Ensayos Clínicos como Asunto , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Farnesiltransferasa , Humanos , Estructura Molecular , Neoplasias/enzimología , Prenilación de Proteína , Relación Estructura-ActividadRESUMEN
[reaction: see text] A one-pot, tandem reductive amination-transamidation-cyclization reaction was employed to produce substituted piperazin-2-ones in good yields. Various amino acid methyl esters and transferable acyl groups were examined to establish the reaction's scope.
Asunto(s)
Piperazinas/síntesis química , Aminación , Ciclización , Modelos Moleculares , Conformación Molecular , Oxidación-ReducciónRESUMEN
A mild method for the synthesis of carbamates from amino alcohols involves sequential carboxylation with carbon dioxide, followed by a Mitsunobu reaction. Unexpectedly, the stereochemical course of the Mitsunobu reaction is dependent on whether the carbamic acid intermediate is N-substituted with hydrogen (retention) or carbon (inversion).
RESUMEN
Controlling the elements of planar and axial chirality are the principal challenges in the synthesis of the aglycon of vancomycin. Vancomycin is the prototypical member of the glycopeptide family of antibiotics which are effective for the treatment of infections by methicillin-resistant Staphylococcus aureus. The first total syntheses of the vancomycin and eremomycin aglycons provide insight into the influence of structure on kinetic and thermodynamic control of atropselective macrocyclizations.