RESUMO
The biotin carboxylase (AccC) is part of the multi-component bacterial acetyl coenzyme-A carboxylase (ACCase) and is essential for pathogen survival. We describe herein the affinity optimization of an initial hit to give 2-(2-chlorobenzylamino)-1-(cyclohexylmethyl)-1H-benzo[d]imidazole-5-carboxamide (1), which was identified using our proprietary Automated Ligand Identification System (ALIS).(1) The X-ray co-crystal structure of 1 was solved and revealed several key interactions and opportunities for further optimization in the ATP site of AccC. Structure Based Drug Design (SBDD) and parallel synthetic approaches resulted in a novel series of AccC inhibitors, exemplified by (R)-2-(2-chlorobenzylamino)-1-(2,3-dihydro-1H-inden-1-yl)-1H-imidazo[4,5-b]pyridine-5-carboxamide (40). This compound is a potent and selective inhibitor of bacterial AccC with an IC(50) of 20 nM and a MIC of 0.8 microg/mL against a sensitized strain of Escherichia coli (HS294 E. coli).
Assuntos
Antibacterianos/farmacologia , Benzimidazóis/farmacologia , Carbono-Nitrogênio Ligases/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Escherichia coli/efeitos dos fármacos , Imidazóis/farmacologia , Ácidos Nicotínicos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Benzimidazóis/síntese química , Benzimidazóis/química , Cristalografia por Raios X , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Imidazóis/síntese química , Imidazóis/química , Ligantes , Testes de Sensibilidade Microbiana , Modelos Moleculares , Ácidos Nicotínicos/síntese química , Ácidos Nicotínicos/química , Relação Estrutura-AtividadeRESUMO
A novel series of non-ATP-competitive MK2 inhibitors based on a furan-2-carboxyamide scaffold was discovered through high-throughput screening using the affinity selection-mass spectrometry-based Automated Ligand Identification System platform. Medicinal chemistry efforts optimized the initial screening hit to leadlike compounds with significant improvements in biochemical and cellular potencies, while maintaining excellent kinase selectivity and in vitro pharmacokinetic properties. Biophysical and biochemical studies confirmed the unique non-ATP-competitive binding mode of this series and suggested that highly selective inhibitors of MK2 should be feasible by targeting the outside ATP pocket.
RESUMO
Pyridine carboxamide-based inhibitors of the hepatitis C virus (HCV) NS5B polymerase were diversified and optimized to a variety of topologically related scaffolds. In particular, the 2-methyl nicotinic acid scaffold was developed into inhibitors with improved biochemical (IC50-GT1b = 0.014 µM) and cell-based HCV replicon potency (EC50-GT1b = 0.7 µM). Biophysical and biochemical characterization identified this novel series of compounds as palm site binders to HCV polymerase.