RESUMEN
The synthesis and antibacterial activity of heterocyclic methylsulfone hydroxamates is presented. Compounds in this series are potent inhibitors of the LpxC enzyme, a key enzyme involved in the production of lipopolysaccharide (LPS) found in the outer membrane of Gram-negative bacteria. SAR evaluation of compounds in this series revealed analogs with potent antibacterial activity against challenging Gram-negative species such as Pseudomonas aeruginosa and Klebsiella pneumoniae.
Asunto(s)
Amidohidrolasas/antagonistas & inhibidores , Antibacterianos/química , Inhibidores Enzimáticos/química , Bacterias Gramnegativas/efectos de los fármacos , Ácidos Hidroxámicos/química , Amidohidrolasas/metabolismo , Antibacterianos/síntesis química , Antibacterianos/farmacología , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Compuestos Heterocíclicos/química , Ácidos Hidroxámicos/síntesis química , Ácidos Hidroxámicos/farmacología , Klebsiella pneumoniae/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/enzimología , Relación Estructura-Actividad , Sulfonas/químicaRESUMEN
The nuclear hormone receptor retinoic acid receptor-related orphan C2 (RORC2, also known as RORγt) is a promising target for the treatment of autoimmune diseases. A small molecule, inverse agonist of the receptor is anticipated to reduce production of IL-17, a key proinflammatory cytokine. Through a high-throughput screening approach, we identified a molecule displaying promising binding affinity for RORC2, inhibition of IL-17 production in Th17 cells, and selectivity against the related RORA and RORB receptor isoforms. Lead optimization to improve the potency and metabolic stability of this hit focused on two key design strategies, namely, iterative optimization driven by increasing lipophilic efficiency and structure-guided conformational restriction to achieve optimal ground state energetics and maximize receptor residence time. This approach successfully identified 3-cyano- N-(3-(1-isobutyrylpiperidin-4-yl)-1-methyl-4-(trifluoromethyl)-1 H-pyrrolo[2,3- b]pyridin-5-yl)benzamide as a potent and selective RORC2 inverse agonist, demonstrating good metabolic stability, oral bioavailability, and the ability to reduce IL-17 levels and skin inflammation in a preclinical in vivo animal model upon oral administration.
Asunto(s)
Diseño de Fármacos , Agonismo Inverso de Drogas , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/agonistas , Piridinas/administración & dosificación , Piridinas/farmacología , Administración Oral , Animales , Disponibilidad Biológica , Evaluación Preclínica de Medicamentos , Humanos , Ratones , Piridinas/farmacocinética , Células Th17/efectos de los fármacos , Células Th17/metabolismoRESUMEN
C5-substituted 2,4-diaminoquinazoline inhibitors of the decapping scavenger enzyme DcpS (DAQ-DcpSi) have been developed for the treatment of spinal muscular atrophy (SMA), which is caused by genetic deficiency in the Survival Motor Neuron (SMN) protein. These compounds are claimed to act as SMN2 transcriptional activators but data underlying that claim are equivocal. In addition it is unclear whether the claimed effects on SMN2 are a direct consequence of DcpS inhibitor or might be a consequence of lysosomotropism, which is known to be neuroprotective. DAQ-DcpSi effects were characterized in cells in vitro utilizing DcpS knockdown and 7-methyl analogues as probes for DcpS vs non-DcpS-mediated effects. We also performed analysis of Smn transcript levels, RNA-Seq analysis of the transcriptome and SMN protein in order to identify affected pathways underlying the therapeutic effect, and studied lysosomotropic and non-lysosomotropic DAQ-DCpSi effects in 2B/- SMA mice. Treatment of cells caused modest and transient SMN2 mRNA increases with either no change or a decrease in SMNΔ7 and no change in SMN1 transcripts or SMN protein. RNA-Seq analysis of DAQ-DcpSi-treated N2a cells revealed significant changes in expression (both up and down) of approximately 2,000 genes across a broad range of pathways. Treatment of 2B/- SMA mice with both lysomotropic and non-lysosomotropic DAQ-DcpSi compounds had similar effects on disease phenotype indicating that the therapeutic mechanism of action is not a consequence of lysosomotropism. In striking contrast to the findings in vitro, Smn transcripts were robustly changed in tissues but there was no increase in SMN protein levels in spinal cord. We conclude that DAQ-DcpSi have reproducible benefit in SMA mice and a broad spectrum of biological effects in vitro and in vivo, but these are complex, context specific, and not the result of simple SMN2 transcriptional activation.
Asunto(s)
Endorribonucleasas/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Atrofia Muscular Espinal/tratamiento farmacológico , Atrofia Muscular Espinal/enzimología , Quinazolinas/farmacología , Animales , Línea Celular , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/química , Femenino , Técnicas de Silenciamiento del Gen , Células HEK293 , Humanos , Masculino , Ratones , Ratones Noqueados , Atrofia Muscular Espinal/genética , Regiones Promotoras Genéticas , Quinazolinas/química , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteína 2 para la Supervivencia de la Neurona Motora/deficiencia , Proteína 2 para la Supervivencia de la Neurona Motora/genética , Proteína 2 para la Supervivencia de la Neurona Motora/metabolismoRESUMEN
This work describes the first rational targeting of tyrosine residues in a protein binding site by small-molecule covalent probes. Specific tyrosine residues in the active site of the mRNA-decapping scavenger enzyme DcpS were modified using reactive sulfonyl fluoride covalent inhibitors. Structure-based molecular design was used to create an alkyne-tagged probe bearing the sulfonyl fluoride warhead, thus enabling the efficient capture of the protein from a complex proteome. Use of the probe in competition experiments with a diaminoquinazoline DcpS inhibitor permitted the quantification of intracellular target occupancy. As a result, diaminoquinazoline upregulators of survival motor neuron protein that are used for the treatment of spinal muscular atrophy were confirmed as inhibitors of DcpS in human primary cells. This work illustrates the utility of sulfonyl fluoride probes designed to react with specific tyrosine residues of a protein and augments the chemical biology toolkit by these probes uses in target validation and molecular pharmacology.
Asunto(s)
Endorribonucleasas/metabolismo , Inhibidores Enzimáticos/farmacología , Sondas Moleculares/química , Ácidos Sulfínicos/química , Tirosina/metabolismo , Dominio Catalítico , Células Cultivadas , Técnicas de Química Sintética , Cristalografía por Rayos X , Endorribonucleasas/antagonistas & inhibidores , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Humanos , Sondas Moleculares/síntesis química , Terapia Molecular Dirigida/métodos , Relación Estructura-Actividad , Tirosina/químicaRESUMEN
Despite its diverse applications, such as identification of the protein binding partners of small molecules and investigation of intracellular drug-target engagement, photoaffinity labelling (PAL) is intrinsically challenging, primarily due to the difficulty in discovering functionally active photoaffinity probes. Here we describe the creation of a chemoproteomic library to discover a novel photoaffinity probe for DcpS, an mRNA decapping enzyme that is a putative target for Spinal Muscular Atrophy. This library approach expedites the discovery of photoaffinity probes and expands the chemical biology toolbox to include RNA cap-binding proteins.
Asunto(s)
Endorribonucleasas/metabolismo , Sondas Moleculares/química , Etiquetas de Fotoafinidad/química , Sitios de Unión , Endorribonucleasas/química , Biblioteca de Genes , Humanos , Modelos Moleculares , Sondas Moleculares/metabolismo , Quinazolinas/químicaRESUMEN
The synthesis and biological activity of a new series of LpxC inhibitors represented by pyridone methylsulfone hydroxamate 2a is presented. Members of this series have improved solubility and free fraction when compared to compounds in the previously described biphenyl methylsulfone hydroxamate series, and they maintain superior Gram-negative antibacterial activity to comparator agents.
Asunto(s)
Amidohidrolasas/antagonistas & inhibidores , Antibacterianos/síntesis química , Bacterias Gramnegativas/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Ácidos Hidroxámicos/síntesis química , Piridonas/síntesis química , Ácidos Sulfónicos/síntesis química , Animales , Antibacterianos/farmacocinética , Antibacterianos/farmacología , Cristalografía por Rayos X , Humanos , Ácidos Hidroxámicos/farmacocinética , Ácidos Hidroxámicos/farmacología , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Estructura Molecular , Conformación Proteica , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/enzimología , Piridonas/farmacocinética , Piridonas/farmacología , Ratas , Estereoisomerismo , Relación Estructura-Actividad , Ácidos Sulfónicos/farmacocinética , Ácidos Sulfónicos/farmacologíaRESUMEN
In this paper, we present the synthesis and SAR as well as selectivity, pharmacokinetic, and infection model data for representative analogues of a novel series of potent antibacterial LpxC inhibitors represented by hydroxamic acid.