RESUMO
There are currently no effective chemotherapeutic drugs approved for the treatment of diffuse intrinsic pontine glioma (DIPG), an aggressive pediatric cancer resident in the pons region of the brainstem. Radiation therapy is beneficial but not curative, with the condition being uniformly fatal. Analysis of the genomic landscape surrounding DIPG has revealed that activin receptor-like kinase-2 (ALK2) constitutes a potential target for therapeutic intervention given its dysregulation in the disease. We adopted an open science approach to develop a series of potent, selective, orally bioavailable, and brain-penetrant ALK2 inhibitors based on the lead compound LDN-214117. Modest structural changes to the C-3, C-4, and C-5 position substituents of the core pyridine ring afforded compounds M4K2009, M4K2117, and M4K2163, each with a superior potency, selectivity, and/or blood-brain barrier (BBB) penetration profile. Robust in vivo pharmacokinetic (PK) properties and tolerability mark these inhibitors as advanced preclinical compounds suitable for further development and evaluation in orthotopic models of DIPG.
Assuntos
Receptores de Ativinas Tipo I/antagonistas & inibidores , Antineoplásicos/farmacologia , Glioma Pontino Intrínseco Difuso/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Descoberta de Drogas , Feminino , Células HEK293 , Humanos , Masculino , Camundongos SCID , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Ratos Sprague-Dawley , Relação Estrutura-AtividadeRESUMO
A deconstruction of previously reported phosphoinositide 3-kinase δ (PI3Kδ) inhibitors and subsequent regrowth led to the identification of a privileged fragment for PI3Kδ, which was exploited to deliver a potent, efficient, and selective lead series with a novel binding mode observed in the PI3Kδ crystal structure.
Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Relação Estrutura-Atividade , Administração por Inalação , Animais , Classe Ia de Fosfatidilinositol 3-Quinase/química , Cristalografia por Raios X , Cães , Avaliação Pré-Clínica de Medicamentos , Canal de Potássio ERG1/metabolismo , Inibidores Enzimáticos/administração & dosagem , Ligação de Hidrogênio , Isoquinolinas/química , Células Madin Darby de Rim Canino , RatosRESUMO
Following the discovery of 4-(substituted amino)-1-alkyl-pyrazolo[3,4-b]pyridine-5-carboxamides as potent and selective phosphodiesterase 4B inhibitors, [Hamblin, J. N.; Angell, T.; Ballentine, S., et al. Bioorg. Med. Chem. Lett.2008, 18, 4237] the SAR of the 5-position was investigated further. A range of substituted heterocycles showed good potencies against PDE4. Optimisation using X-ray crystallography and computational modelling led to the discovery of 16, with sub-nM inhibition of LPS-induced TNF-α production from isolated human peripheral blood mononuclear cells.
Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/química , Compostos Heterocíclicos/química , Inibidores de Fosfodiesterase/química , Pirazóis/química , Piridinas/química , Sítios de Ligação , Simulação por Computador , Cristalografia por Raios X , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Humanos , Modelos Químicos , Modelos Moleculares , Inibidores de Fosfodiesterase/síntese química , Inibidores de Fosfodiesterase/farmacologia , Estrutura Terciária de Proteína , Pirazóis/síntese química , Pirazóis/farmacologia , Piridinas/síntese química , Piridinas/farmacologia , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Optimisation of a high-throughput screening hit resulted in the discovery of 4-(substituted amino)-1-alkyl-pyrazolo[3,4-b]pyridine-5-carboxamides as potent and selective inhibitors of Phosphodiesterase 4 (PDE4). Herein, we describe early SAR studies around this novel template highlighting preferred substituents and rationalization of SAR through X-ray crystal structures of analogues bound to the PDE4 active site. Pyrazolopyridine 20a was found to be a potent and selective PDE4 inhibitor which also inhibits LPS induced TNF-alpha production from isolated human peripheral blood mononuclear cells and has an encouraging rat PK profile suitable for oral dosing.