RESUMEN
Tumour necrosis factor (TNF) is a cytokine belonging to a family of trimeric proteins; it has been shown to be a key mediator in autoimmune diseases such as rheumatoid arthritis and Crohn's disease. While TNF is the target of several successful biologic drugs, attempts to design small molecule therapies directed to this cytokine have not led to approved products. Here we report the discovery of potent small molecule inhibitors of TNF that stabilise an asymmetrical form of the soluble TNF trimer, compromising signalling and inhibiting the functions of TNF in vitro and in vivo. This discovery paves the way for a class of small molecule drugs capable of modulating TNF function by stabilising a naturally sampled, receptor-incompetent conformation of TNF. Furthermore, this approach may prove to be a more general mechanism for inhibiting protein-protein interactions.
Asunto(s)
Antiinflamatorios/farmacología , Artritis Experimental/tratamiento farmacológico , Multimerización de Proteína/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Animales , Antiinflamatorios/uso terapéutico , Artritis Experimental/inmunología , Línea Celular , Cristalografía por Rayos X , Descubrimiento de Drogas , Masculino , Ratones , Simulación de Dinámica Molecular , Infiltración Neutrófila/efectos de los fármacos , Neutrófilos/efectos de los fármacos , Neutrófilos/inmunología , Estabilidad Proteica/efectos de los fármacos , Estructura Cuaternaria de Proteína/efectos de los fármacos , Receptores Tipo I de Factores de Necrosis Tumoral/inmunología , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/ultraestructura , Transducción de Señal/inmunología , Relación Estructura-Actividad , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/aislamiento & purificación , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/ultraestructuraRESUMEN
Aldehyde oxidase (AO) catalyzes oxidations of azaheterocycles and aldehydes, amide hydrolysis, and diverse reductions. AO substrates are rare among marketed drugs, and many candidates failed due to poor pharmacokinetics, interspecies differences, and adverse effects. As most issues arise from complex and poorly understood AO biology, an effective solution is to stop or decrease AO metabolism. This perspective focuses on rational drug design approaches to modulate AO-mediated metabolism in drug discovery. AO biological aspects are also covered, as they are complementary to chemical design and important when selecting the experimental system for risk assessment. The authors' recommendation is an early consideration of AO-mediated metabolism supported by computational and in vitro experimental methods but not an automatic avoidance of AO structural flags, many of which are versatile and valuable building blocks. Preferably, consideration of AO-mediated metabolism should be part of the multiparametric drug optimization process, with the goal to improve overall drug-like properties.
Asunto(s)
Aldehído Oxidasa/metabolismo , Diseño de Fármacos , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Enfermedades Metabólicas/tratamiento farmacológico , Preparaciones Farmacéuticas/metabolismo , Animales , Humanos , Enfermedades Metabólicas/enzimología , Enfermedades Metabólicas/patologíaRESUMEN
Aiming at the design of an allosteric modulator of the neonatal Fc receptor (FcRn)-Immunoglobulin G (IgG) interaction, we developed a new methodology including NMR fragment screening, X-ray crystallography, and magic-angle-spinning (MAS) NMR at 100 kHz after sedimentation, exploiting very fast spinning of the nondeuterated soluble 42 kDa receptor construct to obtain resolved proton-detected 2D and 3D NMR spectra. FcRn plays a crucial role in regulation of IgG and serum albumin catabolism. It is a clinically validated drug target for the treatment of autoimmune diseases caused by pathogenic antibodies via the inhibition of its interaction with IgG. We herein present the discovery of a small molecule that binds into a conserved cavity of the heterodimeric, extracellular domain composed of an α-chain and ß2-microglobulin (ß2m) (FcRnECD, 373 residues). X-ray crystallography was used alongside NMR at 100 kHz MAS with sedimented soluble protein to explore possibilities for refining the compound as an allosteric modulator. Proton-detected MAS NMR experiments on fully protonated [13C,15N]-labeled FcRnECD yielded ligand-induced chemical-shift perturbations (CSPs) for residues in the binding pocket and allosteric changes close to the interface of the two receptor heterodimers present in the asymmetric unit as well as potentially in the albumin interaction site. X-ray structures with and without ligand suggest the need for an optimized ligand to displace the α-chain with respect to ß2m, both of which participate in the FcRnECD-IgG interaction site. Our investigation establishes a method to characterize structurally small molecule binding to nondeuterated large proteins by NMR, even in their glycosylated form, which may prove highly valuable for structure-based drug discovery campaigns.
Asunto(s)
Antígenos de Histocompatibilidad Clase I/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Receptores Fc/metabolismo , Sitio Alostérico , Cristalografía por Rayos X , Células HEK293 , Humanos , LigandosRESUMEN
A series of 4-azaindole inhibitors of c-Met kinase is described. The postulated binding mode was confirmed by an X-ray crystal structure and series optimisation was performed on the basis of this structure. Future directions for series development are discussed.
Asunto(s)
Indoles/química , Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Línea Celular Tumoral , Simulación por Computador , Cristalografía por Rayos X , Descubrimiento de Drogas , Humanos , Indoles/síntesis química , Indoles/farmacología , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-met/metabolismo , Relación Estructura-ActividadRESUMEN
A series of quinoxaline inhibitors of c-Met kinase is described. The postulated binding mode was confirmed by an X-ray crystal structure and optimisation of the series was performed on the basis of this structure. Future directions for development of the series are discussed together with the identification of a novel quinoline scaffold.
Asunto(s)
Inhibidores Enzimáticos/farmacología , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Quinoxalinas/farmacología , Cristalografía por Rayos X , Descubrimiento de Drogas , Inhibidores Enzimáticos/química , Quinoxalinas/química , Relación Estructura-ActividadRESUMEN
Aryl Grignard reagents react stereospecifically with alkenyl halides in the presence of manganese chloride (10%) to afford good yields of cross-coupling products.
RESUMEN
We describe herein an efficient access to the highly substituted cyclopentane unit present in the Nudifloside secoiridoid family via crotyl phosphonamide anion mediated conjugate addition to cyclopentenone.
Asunto(s)
Iridoides/síntesis química , Estructura MolecularRESUMEN
Alkyl- and arylmanganese reagents react with o-chloro or o-bromoaryl ketones to give the substituted ketones in high yields. The cross-coupling reaction is performed under mild conditions (-60 to +40 degrees C, 30 min to 4 h) and takes place with excellent chemoselectivity. [reaction: see text]