RESUMEN
Emerging resistance to current antimalarial medicines underscores the importance of identifying new drug targets and novel compounds. Malaria parasites are purine auxotrophic and import purines via the Plasmodium falciparum equilibrative nucleoside transporter type 1 (PfENT1). We previously showed that PfENT1 inhibitors block parasite proliferation in culture. Our goal was to identify additional, possibly more optimal chemical starting points for a drug discovery campaign. We performed a high throughput screen (HTS) of GlaxoSmithKline's 1.8 million compound library with a yeast-based assay to identify PfENT1 inhibitors. We used a parallel progression strategy for hit validation and expansion, with an emphasis on chemical properties in addition to potency. In one arm, the most active hits were tested for human cell toxicity; 201 had minimal toxicity. The second arm, hit expansion, used a scaffold-based substructure search with the HTS hits as templates to identify over 2000 compounds; 123 compounds had activity. Of these 324 compounds, 175 compounds inhibited proliferation of P. falciparum parasite strain 3D7 with IC50 values between 0.8 and â¼180 µM. One hundred forty-two compounds inhibited PfENT1 knockout (pfent1Δ) parasite growth, indicating they also hit secondary targets. Thirty-two hits inhibited growth of 3D7 but not pfent1Δ parasites. Thus, PfENT1 inhibition was sufficient to block parasite proliferation. Therefore, PfENT1 may be a viable target for antimalarial drug development. Six compounds with novel chemical scaffolds were extensively characterized in yeast-, parasite-, and human-erythrocyte-based assays. The inhibitors showed similar potencies against drug sensitive and resistant P. falciparum strains. They represent attractive starting points for development of novel antimalarial drugs.
Asunto(s)
Antimaláricos/farmacología , Transporte Biológico/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Descubrimiento de Drogas , Plasmodium falciparum/efectos de los fármacos , Purinas/metabolismo , Antimaláricos/química , Eritrocitos/efectos de los fármacos , Técnicas de Inactivación de Genes , Células Hep G2/efectos de los fármacos , Ensayos Analíticos de Alto Rendimiento , Humanos , Malaria/parasitología , Malaria Falciparum/parasitología , Proteínas Portadoras de Nucleobases, Nucleósidos, Nucleótidos y Ácidos Nucleicos/efectos de los fármacos , Proteínas Portadoras de Nucleobases, Nucleósidos, Nucleótidos y Ácidos Nucleicos/genética , Plasmodium falciparum/genética , Plasmodium falciparum/crecimiento & desarrollo , Plasmodium falciparum/metabolismo , Proteínas Protozoarias/efectos de los fármacos , Proteínas Protozoarias/genética , Transcriptoma , Levaduras/efectos de los fármacosRESUMEN
Change history: In this Letter, author Ana Puhl was inadvertently omitted; this error has been corrected online.An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMEN
Stimulator of interferon genes (STING) is a receptor in the endoplasmic reticulum that propagates innate immune sensing of cytosolic pathogen-derived and self DNA1. The development of compounds that modulate STING has recently been the focus of intense research for the treatment of cancer and infectious diseases and as vaccine adjuvants2. To our knowledge, current efforts are focused on the development of modified cyclic dinucleotides that mimic the endogenous STING ligand cGAMP; these have progressed into clinical trials in patients with solid accessible tumours amenable to intratumoral delivery3. Here we report the discovery of a small molecule STING agonist that is not a cyclic dinucleotide and is systemically efficacious for treating tumours in mice. We developed a linking strategy to synergize the effect of two symmetry-related amidobenzimidazole (ABZI)-based compounds to create linked ABZIs (diABZIs) with enhanced binding to STING and cellular function. Intravenous administration of a diABZI STING agonist to immunocompetent mice with established syngeneic colon tumours elicited strong anti-tumour activity, with complete and lasting regression of tumours. Our findings represent a milestone in the rapidly growing field of immune-modifying cancer therapies.
Asunto(s)
Bencimidazoles/química , Bencimidazoles/farmacología , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/inmunología , Diseño de Fármacos , Proteínas de la Membrana/agonistas , Animales , Bencimidazoles/administración & dosificación , Bencimidazoles/uso terapéutico , Humanos , Ligandos , Proteínas de la Membrana/inmunología , Ratones , Modelos Moleculares , Nucleótidos Cíclicos/metabolismoRESUMEN
This corrects the article DOI: 10.1038/ncomms16081.
RESUMEN
The identification and prioritization of chemically tractable therapeutic targets is a significant challenge in the discovery of new medicines. We have developed a novel method that rapidly screens multiple proteins in parallel using DNA-encoded library technology (ELT). Initial efforts were focused on the efficient discovery of antibacterial leads against 119 targets from Acinetobacter baumannii and Staphylococcus aureus. The success of this effort led to the hypothesis that the relative number of ELT binders alone could be used to assess the ligandability of large sets of proteins. This concept was further explored by screening 42 targets from Mycobacterium tuberculosis. Active chemical series for six targets from our initial effort as well as three chemotypes for DHFR from M. tuberculosis are reported. The findings demonstrate that parallel ELT selections can be used to assess ligandability and highlight opportunities for successful lead and tool discovery.
Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/farmacología , Descubrimiento de Drogas/métodos , Biblioteca de Genes , Mycobacterium tuberculosis/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas , Staphylococcus aureus/efectos de los fármacos , Acinetobacter baumannii/metabolismo , Evaluación Preclínica de Medicamentos , Terapia Molecular Dirigida , Mycobacterium tuberculosis/metabolismo , Staphylococcus aureus/metabolismoRESUMEN
DNA-encoded small-molecule library technology has recently emerged as a new paradigm for identifying ligands against drug targets. To date, this technology has been used with soluble protein targets that are produced and used in a purified state. Here, we describe a cell-based method for identifying small-molecule ligands from DNA-encoded libraries against integral membrane protein targets. We use this method to identify novel, potent, and specific inhibitors of NK3, a member of the tachykinin family of G-protein coupled receptors (GPCRs). The method is simple and broadly applicable to other GPCRs and integral membrane proteins. We have extended the application of DNA-encoded library technology to membrane-associated targets and demonstrate the feasibility of selecting DNA-tagged, small-molecule ligands from complex combinatorial libraries against targets in a heterogeneous milieu, such as the surface of a cell.
Asunto(s)
Acetatos/farmacología , ADN/química , Quinolinas/farmacología , Receptores de Neuroquinina-3/antagonistas & inhibidores , Bibliotecas de Moléculas Pequeñas/farmacología , Acetatos/química , Relación Dosis-Respuesta a Droga , Células HEK293 , Humanos , Ligandos , Estructura Molecular , Quinolinas/química , Bibliotecas de Moléculas Pequeñas/síntesis química , Bibliotecas de Moléculas Pequeñas/química , Relación Estructura-ActividadRESUMEN
The sirtuins SIRT1, SIRT2, and SIRT3 are NAD(+) dependent deacetylases that are considered potential targets for metabolic, inflammatory, oncologic, and neurodegenerative disorders. Encoded library technology (ELT) was used to affinity screen a 1.2 million heterocycle enriched library of DNA encoded small molecules, which identified pan-inhibitors of SIRT1/2/3 with nanomolar potency (e.g., 11c: IC50 = 3.6, 2.7, and 4.0 nM for SIRT1, SIRT2, and SIRT3, respectively). Subsequent SAR studies to improve physiochemical properties identified the potent drug like analogues 28 and 31. Crystallographic studies of 11c, 28, and 31 bound in the SIRT3 active site revealed that the common carboxamide binds in the nicotinamide C-pocket and the aliphatic portions of the inhibitors extend through the substrate channel, explaining the observable SAR. These pan SIRT1/2/3 inhibitors, representing a novel chemotype, are significantly more potent than currently available inhibitors, which makes them valuable tools for sirtuin research.
Asunto(s)
Descubrimiento de Drogas , Pirimidinas/química , Pirimidinas/farmacología , Sirtuinas/antagonistas & inhibidores , Humanos , Modelos Moleculares , Conformación Proteica , Sirtuina 1/antagonistas & inhibidores , Sirtuina 1/química , Sirtuina 2/antagonistas & inhibidores , Sirtuina 2/química , Sirtuina 3/antagonistas & inhibidores , Sirtuina 3/química , Sirtuinas/químicaRESUMEN
High throughput screening of the corporate compound collection led to the identification of a novel series of 2-amino-9-aryl-3-cyano-4-methyl-7-oxo-6,7,8,9-tetrahydropyrido[2',3':4,5]thieno[2,3-b]pyridine derivatives as selective PR agonists. Initial SAR exploration leading to potent and selective agonists 9 and 11, X-ray crystal structure of 9 bound to PR-LBD and preliminary developability data are described.
Asunto(s)
Piridinas/química , Piridonas/química , Receptores de Progesterona/agonistas , Tiofenos/química , Animales , Sitios de Unión , Simulación por Computador , Cristalografía por Rayos X , Humanos , Microsomas Hepáticos/metabolismo , Conformación Molecular , Piridinas/síntesis química , Piridinas/farmacología , Piridonas/síntesis química , Piridonas/farmacología , Ratas , Receptores de Progesterona/metabolismo , Relación Estructura-Actividad , Tiofenos/síntesis química , Tiofenos/farmacologíaRESUMEN
A series of N-arylpiperazine camphor sulfonamides was discovered as novel CXCR3 antagonists. The synthesis, structure-activity relationships, and optimization of the initial hit that resulted in the identification of potent and selective CXCR3 antagonists are described.
Asunto(s)
Alcanfor/análogos & derivados , Receptores CXCR3/antagonistas & inhibidores , Sulfonamidas/síntesis química , Alcanfor/síntesis química , Alcanfor/farmacología , Humanos , Piperazinas , Relación Estructura-Actividad , Sulfonamidas/farmacologíaRESUMEN
High-throughput screening of the GSK compound collection against the P2Y(1) receptor identified a novel series of tetrahydro-4-quinolinamine antagonists. Optimal substitution around the piperidine group was pivotal for ensuring activity. An exemplar analog from this series was shown to inhibit platelet aggregation.
Asunto(s)
Aminoquinolinas/síntesis química , Aminoquinolinas/farmacología , Inhibidores de Agregación Plaquetaria/síntesis química , Inhibidores de Agregación Plaquetaria/farmacología , Antagonistas del Receptor Purinérgico P2 , Aminoquinolinas/química , Técnicas Químicas Combinatorias , Humanos , Estructura Molecular , Inhibidores de Agregación Plaquetaria/química , Receptores Purinérgicos P2/metabolismo , Receptores Purinérgicos P2Y1 , Estereoisomerismo , Relación Estructura-Actividad , Trombosis/tratamiento farmacológicoRESUMEN
A series of amino acid anthranilamide derivatives identified from a high-throughput screening campaign as novel, potent, and glucose-sensitive inhibitors of human liver glycogen phosphorylase a are described. A solid-phase synthesis using Wang resin was also developed which provided efficient access to a variety of analogues, and resulted in the identification of key structure-activity relationships, and the discovery of a potent exemplar (IC(50)=80 nM). The SAR scope, synthetic strategy, and in vitro results for this series are presented herein.
Asunto(s)
Glucógeno Fosforilasa de Forma Hepática/antagonistas & inhibidores , ortoaminobenzoatos/química , Aminoácidos/química , Animales , Química Farmacéutica/métodos , Diseño de Fármacos , Glucógeno Fosforilasa de Forma Hepática/química , Humanos , Concentración 50 Inhibidora , Hígado/enzimología , Microsomas Hepáticos/enzimología , Modelos Químicos , Ratas , Relación Estructura-Actividad , Urea/química , ortoaminobenzoatos/farmacologíaRESUMEN
A series of 3-phenyl-2-propenamides discovered from a high-throughput screening campaign as novel, potent, glucose-sensitive inhibitors of human liver glycogen phosphorylase a is described. A solid-phase synthesis on DMHB resin was also developed which provided efficient access not only to certain analogues that could not be cleanly made using more traditional means, but also to a variety of additional analogues. The SAR scope and synthetic strategy are presented herein.
Asunto(s)
Acrilamidas/síntesis química , Acrilamidas/farmacología , Inhibidores Enzimáticos/farmacología , Glucógeno Fosforilasa/antagonistas & inhibidores , Técnicas Químicas Combinatorias , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/síntesis química , Humanos , Hígado/enzimología , Resinas Sintéticas/química , Relación Estructura-ActividadRESUMEN
An efficient, asymmetric solid-phase synthesis of benzothiadiazine-substituted tetramic acids is reported. Starting from commercially available chiral Fmoc-protected alpha-amino acids loaded onto Wang resin, Fmoc removal, reductive amination followed by amide bond formation, and base-catalyzed cyclization with simultaneous cleavage from the resin provided the desired products. Compounds described are potent inhibitors of the hepatitis C virus RNA-dependent RNA polymerase.