RESUMO
An integrated workflow has been established that enables the synthesis, purification, and subsequent biological testing of compound libraries on a microgram scale. This approach utilizes mass directed preparative HPLC in conjunction with charged aerosol detection (CAD) to generate solutions of investigational compounds at high purity and standardized concentrations, facilitating high fidelity biological testing. This new workflow successfully delivered libraries of histone deacetylase (HDAC) inhibitors that afforded biological data consistent with that obtained from standard scale parallel medicinal chemistry techniques. The advantages of this new approach to library synthesis include greatly reduced material requirements and amenability to high-throughput experimentation.
RESUMO
The selectivity of histone deacetylase inhibitors (HDACis) is greatly impacted by the zinc binding groups. In an effort to search for novel zinc binding groups, we applied a parallel medicinal chemistry (PMC) strategy to quickly synthesize substituted benzamide libraries. We discovered a series containing 2-substituted benzamides as the zinc binding group which afforded highly selective and potent HDAC3 inhibitors, exemplified by compound 16 with a 2-methylthiobenzamide. Compound 16 inhibited HDAC3 with an IC50 of 30 nM and with unprecedented selectivity of >300-fold over all other HDAC isoforms. Interestingly, a subtle change of the 2-methylthio to a 2-hydroxy benzamide in 20 retains HDAC3 potency but loses all selectivity over HDAC 1 and 2. This significant difference in selectivity was rationalized by X-ray crystal structures of HDACis 16 and 20 bound to HDAC2, revealing different binding modes to the catalytic zinc ion. This series of HDAC3 selective inhibitors served as tool compounds for investigating the minimal set of HDAC isoforms that must be inhibited for the HIV latency activation in a Jurkat 2C4 cell model and potentially as leads for selective HDAC3 inhibitors for other indications.
RESUMO
Bruton's tyrosine kinase (BTK) is a Tec family kinase with a well-defined role in the B cell receptor (BCR) pathway. It has become an attractive kinase target for selective B cell inhibition, and for the treatment of B cell related diseases. Many BTK inhibitors have been discovered for the treatment of cancer and rheumatoid arthritis, including a series of BTK inhibitors based on 8-amino-imidazo[1,5-a]pyrazine we recently reported. The X-ray crystal structures of BTK with inhibitors were also published, which provided great help for the SAR design. Here we report our SAR work introducing ring constraints for the 3-position piperidine amides on the BTK inhibitors based on 8-amino-imidazo[1,5-a]pyrazine. This modification improved the potency in BTK inhibitions, as well as the PK profile and the off-target selectivity. The dose-dependent efficacy of two BTK inhibitors was observed in the rat collagen induced arthritis (CIA) model.
Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Imidazóis/química , Inibidores de Proteínas Quinases/química , Pirazinas/química , Tirosina Quinase da Agamaglobulinemia/metabolismo , Animais , Artrite Experimental/tratamento farmacológico , Sítios de Ligação , Compostos Bicíclicos com Pontes/química , Cristalografia por Raios X , Modelos Animais de Doenças , Cães , Relação Dose-Resposta a Droga , Meia-Vida , Humanos , Imidazóis/metabolismo , Imidazóis/uso terapêutico , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Pirazinas/metabolismo , Pirazinas/uso terapêutico , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/metabolismoRESUMO
HIV persistence in latently infected, resting CD4+ T cells is broadly considered a barrier to eradicate HIV. Activation of the provirus using latency-reversing agents (LRAs) followed by immune-mediated clearance to purge reservoirs has been touted as a promising therapeutic approach. Histone deacetylases (HDACs) and histone acetyltransferases (HATs) control the acetylation level of lysine residues in histones to regulate the gene transcription. Several clinical HDAC inhibitors had been examined as LRAs, which induced HIV activation in vitro and in vivo. Here we report the discovery of a series of selective and potent class I HDAC inhibitors based on aryl ketones as a zinc binding group, which reversed HIV latency using a Jurkat model of HIV latency in 2C4 cells. The SAR led to the discovery of a highly selective class I HDAC inhibitor 10 with excellent potency. HDACi 10 induces the HIV gag P24 protein in patient latent CD4+ T cells.
RESUMO
A series of novel tetracyclic core-containing HCV NS5A inhibitors has been discovered. Incorporation of tetrahydropyran-substituted amino acid moiety improved their potency and yielded HCV NS5A inhibitors with a minimum potency shift from the GT1a strain compared to other genotypes and mutants. Compounds 53 and 54 showed the best potency profile and had reasonable half-times in rat PK studies. However, further optimization of their oral bioavailability is still needed in order to advance them for further development. [BMCL ABSTRACT] ©2000 Elsevier Science Ltd. All rights reserved.
Assuntos
Antivirais/farmacologia , Descoberta de Drogas , Genótipo , Hepacivirus/efeitos dos fármacos , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/química , Antivirais/farmacocinética , Meia-Vida , RatosRESUMO
We describe the discovery of MK-6169, a potent and pan-genotype hepatitis C virus NS5A inhibitor with optimized activity against common resistance-associated substitutions. SAR studies around the combination of changes to both the valine and aminal carbon region of elbasvir led to the discovery of a series of compounds with substantially improved potency against common resistance-associated substitutions in the major genotypes, as well as good pharmacokinetics in both rat and dog. Through further optimization of key leads from this effort, MK-6169 (21) was discovered as a preclinical candidate for further development.
Assuntos
Antivirais/farmacologia , Descoberta de Drogas , Farmacorresistência Viral/efeitos dos fármacos , Hepacivirus/efeitos dos fármacos , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/farmacocinética , Cães , Genótipo , Hepacivirus/genética , Hepacivirus/metabolismo , Masculino , Ratos , Distribuição TecidualRESUMO
HCV NS5A inhibitors have shown impressive in vitro potency profiles in HCV replicon assays thus making them attractive components for inclusion in an all oral fixed dose combination regimen. Herein, we describe the discovery and characterization of silyl proline-containing HCV NS5A inhibitor MK-8325 with good pan-genotype activity and acceptable pharmacokinetic properties.
Assuntos
Antivirais/química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Prolina/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/farmacocinética , Antivirais/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Cães , Genótipo , Meia-Vida , Haplorrinos , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Hepacivirus/fisiologia , Compostos Heterocíclicos de 4 ou mais Anéis/farmacocinética , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Ratos , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacosRESUMO
8-Amino-imidazo[1,5-a]pyrazine-based Bruton's tyrosine kinase (BTK) inhibitors, such as 6, exhibited potent inhibition of BTK but required improvements in both kinase and hERG selectivity (Liu et al., 2016; Gao et al., 2017). In an effort to maintain the inhibitory activity of these analogs and improve their selectivity profiles, we carried out SAR exploration of groups at the 3-position of pyrazine compound 6. This effort led to the discovery of the morpholine group as an optimized pharmacophore. Compounds 13, 23 and 38 displayed excellent BTK potencies, kinase and hERG selectivities, and pharmacokinetic profiles.
Assuntos
Artrite Reumatoide/tratamento farmacológico , Descoberta de Drogas , Imidazóis/farmacologia , Morfolinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Artrite Reumatoide/metabolismo , Relação Dose-Resposta a Droga , Humanos , Imidazóis/síntese química , Imidazóis/química , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Modelos Moleculares , Estrutura Molecular , Morfolinas/síntese química , Morfolinas/química , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Tirosina Quinases/metabolismo , Relação Estrutura-Atividade , Regulador Transcricional ERG/antagonistas & inibidores , Regulador Transcricional ERG/metabolismoRESUMO
Our research on hydantoin based TNF-α converting enzyme (TACE) inhibitors led to fused bi-heteroaryl hydantoin series that demonstrate sub-nanomolar potency (Ki) as well as excellent activity in human whole blood (hWBA). However, lead compound 2 posed some formulation challenges which prevented it for further development. A prodrug approach was investigated to address this issue. The pivalate prodrug 3 can be formulated as stable neutral form and demonstrated improved DMPK properties when compared with parent compound.
Assuntos
Proteína ADAM17/antagonistas & inibidores , Hidantoínas/química , Hidantoínas/síntese química , Hidantoínas/farmacologia , Ácidos Pentanoicos/química , Pró-Fármacos/síntese química , Pró-Fármacos/farmacologia , Proteína ADAM17/metabolismo , Administração Oral , Animais , Área Sob a Curva , Cães , Ativação Enzimática/efeitos dos fármacos , Meia-Vida , Haplorrinos , Humanos , Hidantoínas/administração & dosagem , Hidantoínas/farmacocinética , Ácidos Pentanoicos/administração & dosagem , Ácidos Pentanoicos/farmacocinética , Pró-Fármacos/administração & dosagem , Pró-Fármacos/farmacocinética , Curva ROC , Ratos , Relação Estrutura-AtividadeRESUMO
We have identified a series of hydantoin-derived TNF-a converting enzyme (TACE) inhibitors containing a pendant fused bi-heteroaryl group, which demonstrate sub-nanomolar potency (Ki), excellent activity in human whole blood assay, and improved DMPK profiles over prior series.
Assuntos
Proteína ADAM17/antagonistas & inibidores , Hidantoínas/química , Inibidores de Proteases/química , Proteína ADAM17/metabolismo , Animais , Área Sob a Curva , Cães , Ativação Enzimática/efeitos dos fármacos , Meia-Vida , Haplorrinos , Humanos , Hidantoínas/síntese química , Hidantoínas/farmacologia , Inibidores de Proteases/síntese química , Inibidores de Proteases/farmacologia , Curva ROC , Ratos , Relação Estrutura-AtividadeRESUMO
We describe the research that led to the discovery of compound 40 (ruzasvir, MK-8408), a pan-genotypic HCV nonstructural protein 5A (NS5A) inhibitor with a "flat" GT1 mutant profile. This NS5A inhibitor contains a unique tetracyclic indole core while maintaining the imidazole-proline-valine Moc motifs of our previous NS5A inhibitors. Compound 40 is currently in early clinical trials and is under evaluation as part of an all-oral DAA regimen for the treatment of chronic HCV infection.
Assuntos
Antivirais/química , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Polimorfismo Genético , Pirrolidinas/química , Pirrolidinas/farmacologia , Tiazóis/química , Tiazóis/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/farmacocinética , Linhagem Celular , Cães , Haplorrinos , Hepacivirus/genética , Compostos Heterocíclicos de 4 ou mais Anéis/farmacocinética , Humanos , Pirrolidinas/farmacocinética , Ratos , Relação Estrutura-Atividade , Tiazóis/farmacocinéticaRESUMO
The discovery of potent and pan-genotypic HCV NS5A inhibitors faces many challenges including the significant diversity among genotypes, substantial potency shift conferred on some key resistance-associated variants, inconsistent SARs between different genotypes and mutants, and the lacking of models of inhibitor/protein complexes for rational inhibitor design. As part of ongoing efforts on HCV NS5A inhibition at Merck, we now describe the discovery of a novel series of chromane containing NS5A inhibitors. SAR studies around the "Z" group of the tetracyclic indole scaffold explored fused bicyclic rings as alternates to the phenyl group of elbasvir (1, MK-8742) and identified novel chromane and 2,3-dihydrobenzofuran derivatives as "Z" group replacements offered good potency across all genotypes. This effort, incorporating the C-1 fluoro substitution at the tetracyclic indole core, led to the discovery of a new series of NS5A inhibitors, such as compounds 14 and 25-28, with significantly improved potency against resistance-associated variants, such as GT2b, GT1a Y93H, and GT1a L31V. Compound 14 also showed reasonable PK exposures in preclinical species (rat and dog).
Assuntos
Antivirais/farmacologia , Cromanos/farmacologia , Descoberta de Drogas , Farmacorresistência Viral/efeitos dos fármacos , Hepacivirus/efeitos dos fármacos , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/síntese química , Antivirais/química , Cromanos/síntese química , Cromanos/química , Cães , Relação Dose-Resposta a Droga , Masculino , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ratos , Ratos Wistar , Relação Estrutura-AtividadeRESUMO
Herein, we describe our research efforts to develop unique cores in molecules which function as HCV nonstructural protein 5A (NS5A) inhibitors. In particular, various fused tetracyclic cores were identified which showed genotype and mutant activities comparable to the indole-based tetracyclic core.
Assuntos
Indóis/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacosRESUMO
We describe the impact of proline modifications, in our tetracyclic-indole based series of nonstructural protein 5A (NS5A) inhibitors, to their replicon profiles. This work identified NS5A inhibitors with an improved and flattened resistance profiles.
Assuntos
Antivirais/farmacologia , Benzofuranos/farmacologia , Imidazóis/farmacologia , Indóis/química , Prolina/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/química , Benzofuranos/química , Imidazóis/química , Relação Estrutura-AtividadeRESUMO
As part of an ongoing effort in NS5A inhibition at Merck we now describe our efforts for introducing substitution around the tetracyclic indole core of MK-8742. Fluoro substitution on the core combined with the fluoro substitutions on the proline ring improved the potency against GT1a Y93H significantly. However, no improvement on GT2b potency was achieved. Limiting the fluoro substitution to C-1 of the tetracyclic indole core had a positive impact on the potency against the resistance associated variants, such as GT1a Y93H and GT2b, and the PK profile as well. Compounds, such as 62, with reduced potency shifts between wild type GT1a to GT2b, GT1a Y93H, and GT1a L31V were identified.
Assuntos
Antivirais/farmacologia , Benzofuranos/farmacologia , Imidazóis/farmacologia , Indóis/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/química , Antivirais/farmacocinética , Benzofuranos/química , Benzofuranos/farmacocinética , Imidazóis/química , Imidazóis/farmacocinética , Indóis/química , Indóis/farmacocinética , Relação Estrutura-AtividadeRESUMO
A matched and mixed capping SAR study was conducted on the tetracyclic indole class of HCV NS5A inhibitors to examine the influence of modifications of this region on the overall HCV virologic resistance profiles.
Assuntos
Antivirais/química , Hepacivirus/metabolismo , Indóis/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/metabolismo , Antivirais/farmacologia , Área Sob a Curva , Genótipo , Meia-Vida , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Indóis/metabolismo , Indóis/farmacologia , Curva ROC , Ratos , Relação Estrutura-Atividade , Proteínas não Estruturais Virais/metabolismoRESUMO
Herein we describe our research efforts around the aryl and heteroaryl substitutions at the aminal carbon of the tetracyclic indole-based HCV NS5A inhibitor MK-8742. A series of potent NS5A inhibitors are described, such as compounds 45-47, 54, 56, and 65, which showed improved potency against clinically relevant and resistance associated HCV variants. The improved potency profiles of these compounds demonstrated an SAR that can improve the potency against GT2b, GT1a Y93H, and GT1a L31V altogether, which was unprecedented in our previous efforts in NS5A inhibition.
Assuntos
Antivirais/farmacologia , Benzofuranos/farmacologia , Hepacivirus/efeitos dos fármacos , Imidazóis/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/síntese química , Antivirais/química , Benzofuranos/síntese química , Benzofuranos/química , Relação Dose-Resposta a Droga , Imidazóis/síntese química , Imidazóis/química , Masculino , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Relação Estrutura-AtividadeRESUMO
HCV NS5A inhibitors have demonstrated impressive in vitro potency profiles in HCV replicon assays and robust HCV RNA titer reduction in the clinic making them attractive components for inclusion in an all oral fixed dose combination regimen for the treatment of HCV infection. Herein we describe our continued research efforts around the alkyl "Z group" modification of the tetracyclic indole-based NS5A inhibitor MK-8742, which led to the discovery of a series of potent NS5A inhibitors. Compounds 10 and 19 are of particular interests since they are as potent as our previous leads and have much improved rat pharmacokinetic profiles.
Assuntos
Antivirais/farmacologia , Benzofuranos/farmacologia , Hepacivirus/efeitos dos fármacos , Imidazóis/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/síntese química , Antivirais/química , Benzofuranos/síntese química , Benzofuranos/química , Relação Dose-Resposta a Droga , Hepatite C/tratamento farmacológico , Imidazóis/síntese química , Imidazóis/química , Masculino , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacosRESUMO
HCV NS5A inhibitors have demonstrated impressive in vitro virologic profiles in HCV replicon assays and robust HCV RNA titer reduction in the clinic making them attractive components for inclusion in an all oral fixed-dose combination (FDC) regimen for the treatment of HCV infection. Merck's effort in this area identified MK-4882 and MK-8325 as early development leads. Herein, we describe the discovery of potent macrocyclic NS5A inhibitors bearing the MK-8325 or MK-4882 core structure.
Assuntos
Antivirais/farmacologia , Descoberta de Drogas , Hepacivirus/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Compostos Macrocíclicos/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/síntese química , Antivirais/química , Relação Dose-Resposta a Droga , Hepatite C/tratamento farmacológico , Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Macrocíclicos/síntese química , Compostos Macrocíclicos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacosRESUMO
HCV NS5A inhibitors have demonstrated impressive in vitro potency profiles in HCV replicon assays and robust HCV RNA titer reduction in the clinic making them attractive components for inclusion in an all oral fixed dose combination regimen for the treatment of HCV infection. Herein, we describe research efforts that led to the discovery of a series of fused tricyclic core containing HCV NS5A inhibitors such as 24, 39, 40, 43, and 44 which have pan-genotype activity and are orally bioavailable in the rat.