RESUMEN
To facilitate the detection and management of potential clinical antiviral resistance, in vitro selection of drug-resistant severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) against the virus Mpro inhibitor nirmatrelvir (Paxlovid active component) was conducted. Six Mpro mutation patterns containing T304I alone or in combination with T21I, L50F, T135I, S144A, or A173V emerged, with A173V+T304I and T21I+S144A+T304I mutations showing >20-fold resistance each. Biochemical analyses indicated inhibition constant shifts aligned to antiviral results, with S144A and A173V each markedly reducing nirmatrelvir inhibition and Mpro activity. SARS-CoV-2 surveillance revealed that in vitro resistance-associated mutations from our studies and those reported in the literature were rarely detected in the Global Initiative on Sharing All Influenza Data database. In the Paxlovid Evaluation of Protease Inhibition for COVID-19 in High-Risk Patients trial, E166V was the only emergent resistance mutation, observed in three Paxlovid-treated patients, none of whom experienced COVID-19-related hospitalization or death.
Asunto(s)
Antivirales , Tratamiento Farmacológico de COVID-19 , Farmacorresistencia Viral , Mutación , SARS-CoV-2 , SARS-CoV-2/genética , SARS-CoV-2/efectos de los fármacos , Farmacorresistencia Viral/genética , Humanos , Antivirales/farmacología , Antivirales/uso terapéutico , COVID-19/virología , COVID-19/genética , COVID-19/epidemiología , Proteasas 3C de Coronavirus/genética , Proteasas 3C de Coronavirus/antagonistas & inhibidores , Lactamas , Leucina , Nitrilos , ProlinaRESUMEN
Despite the record-breaking discovery, development and approval of vaccines and antiviral therapeutics such as Paxlovid, coronavirus disease 2019 (COVID-19) remained the fourth leading cause of death in the world and third highest in the United States in 2022. Here, we report the discovery and characterization of PF-07817883, a second-generation, orally bioavailable, SARS-CoV-2 main protease inhibitor with improved metabolic stability versus nirmatrelvir, the antiviral component of the ritonavir-boosted therapy Paxlovid. We demonstrate the in vitro pan-human coronavirus antiviral activity and off-target selectivity profile of PF-07817883. PF-07817883 also demonstrated oral efficacy in a mouse-adapted SARS-CoV-2 model at plasma concentrations equivalent to nirmatrelvir. The preclinical in vivo pharmacokinetics and metabolism studies in human matrices are suggestive of improved oral pharmacokinetics for PF-07817883 in humans, relative to nirmatrelvir. In vitro inhibition/induction studies against major human drug metabolizing enzymes/transporters suggest a low potential for perpetrator drug-drug interactions upon single-agent use of PF-07817883.
RESUMEN
KAT6A, and its paralog KAT6B, are histone lysine acetyltransferases (HAT) that acetylate histone H3K23 and exert an oncogenic role in several tumor types including breast cancer where KAT6A is frequently amplified/overexpressed. However, pharmacologic targeting of KAT6A to achieve therapeutic benefit has been a challenge. Here we describe identification of a highly potent, selective, and orally bioavailable KAT6A/KAT6B inhibitor CTx-648 (PF-9363), derived from a benzisoxazole series, which demonstrates anti-tumor activity in correlation with H3K23Ac inhibition in KAT6A over-expressing breast cancer. Transcriptional and epigenetic profiling studies show reduced RNA Pol II binding and downregulation of genes involved in estrogen signaling, cell cycle, Myc and stem cell pathways associated with CTx-648 anti-tumor activity in ER-positive (ER+) breast cancer. CTx-648 treatment leads to potent tumor growth inhibition in ER+ breast cancer in vivo models, including models refractory to endocrine therapy, highlighting the potential for targeting KAT6A in ER+ breast cancer.
Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/genética , Histonas/metabolismo , Histona Acetiltransferasas/genética , Histona Acetiltransferasas/metabolismo , Transducción de Señal , Línea Celular TumoralRESUMEN
The COVID-19 pandemic continues to be a public health threat with emerging variants of SARS-CoV-2. Nirmatrelvir (PF-07321332) is a reversible, covalent inhibitor targeting the main protease (Mpro) of SARS-CoV-2 and the active protease inhibitor in PAXLOVID (nirmatrelvir tablets and ritonavir tablets). However, the efficacy of nirmatrelvir is underdetermined against evolving SARS-CoV-2 variants. Here, we evaluated the in vitro catalytic activity and potency of nirmatrelvir against the Mpro of prevalent variants of concern (VOCs) or variants of interest (VOIs): Alpha (α, B.1.1.7), Beta (ß, B.1.351), Delta (δ, B1.617.2), Gamma (γ, P.1), Lambda (λ, B.1.1.1.37/C37), Omicron (ο, B.1.1.529), as well as the original Washington or wildtype strain. These VOCs/VOIs carry prevalent mutations at varying frequencies in the Mpro specifically for α, ß, γ (K90R), λ (G15S), and ο (P132H). In vitro biochemical enzymatic assay characterization of the enzyme kinetics of the mutant Mpros demonstrates that they are catalytically comparable to wildtype. We found that nirmatrelvir has similar potency against each mutant Mpro including P132H that is observed in the Omicron variant with a Ki of 0.635 nM as compared to a Ki of 0.933 nM for wildtype. The molecular basis for these observations were provided by solution-phase structural dynamics and structural determination of nirmatrelvir bound to the ο, λ, and ß Mpro at 1.63 to 2.09 Å resolution. These in vitro data suggest that PAXLOVID has the potential to maintain plasma concentrations of nirmatrelvir many-fold times higher than the amount required to stop the SARS-CoV-2 VOC/VOI, including Omicron, from replicating in cells.
Asunto(s)
Tratamiento Farmacológico de COVID-19 , COVID-19 , Lactamas/química , SARS-CoV-2 , Inhibidores de Proteasa Viral/química , COVID-19/virología , Proteasas 3C de Coronavirus , Cisteína Endopeptidasas/metabolismo , Humanos , Leucina , Nitrilos , Pandemias , Prolina , SARS-CoV-2/efectos de los fármacos , Proteínas Virales/metabolismoRESUMEN
The worldwide outbreak of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global pandemic. Alongside vaccines, antiviral therapeutics are an important part of the healthcare response to countering the ongoing threat presented by COVID-19. Here, we report the discovery and characterization of PF-07321332, an orally bioavailable SARS-CoV-2 main protease inhibitor with in vitro pan-human coronavirus antiviral activity and excellent off-target selectivity and in vivo safety profiles. PF-07321332 has demonstrated oral activity in a mouse-adapted SARS-CoV-2 model and has achieved oral plasma concentrations exceeding the in vitro antiviral cell potency in a phase 1 clinical trial in healthy human participants.
Asunto(s)
Tratamiento Farmacológico de COVID-19 , Lactamas/farmacología , Lactamas/uso terapéutico , Leucina/farmacología , Leucina/uso terapéutico , Nitrilos/farmacología , Nitrilos/uso terapéutico , Prolina/farmacología , Prolina/uso terapéutico , SARS-CoV-2/efectos de los fármacos , Inhibidores de Proteasa Viral/farmacología , Inhibidores de Proteasa Viral/uso terapéutico , Administración Oral , Animales , COVID-19/virología , Ensayos Clínicos Fase I como Asunto , Coronavirus/efectos de los fármacos , Modelos Animales de Enfermedad , Quimioterapia Combinada , Humanos , Lactamas/administración & dosificación , Lactamas/farmacocinética , Leucina/administración & dosificación , Leucina/farmacocinética , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Nitrilos/administración & dosificación , Nitrilos/farmacocinética , Prolina/administración & dosificación , Prolina/farmacocinética , Ensayos Clínicos Controlados Aleatorios como Asunto , Ritonavir/administración & dosificación , Ritonavir/uso terapéutico , SARS-CoV-2/fisiología , Inhibidores de Proteasa Viral/administración & dosificación , Inhibidores de Proteasa Viral/farmacocinética , Replicación Viral/efectos de los fármacosRESUMEN
Two novel compounds were identified as Naa50 binders/inhibitors using DNA-encoded technology screening. Biophysical and biochemical data as well as cocrystal structures were obtained for both compounds (3a and 4a) to understand their mechanism of action. These data were also used to rationalize the binding affinity differences observed between the two compounds and a MLGP peptide-containing substrate. Cellular target engagement experiments further confirm the Naa50 binding of 4a and demonstrate its selectivity toward related enzymes (Naa10 and Naa60). Additional analogs of inhibitor 4a were also evaluated to study the binding mode observed in the cocrystal structures.
RESUMEN
Tropomyosin receptor kinases (TrkA, TrkB, TrkC) are activated by hormones of the neurotrophin family: nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), neurotrophin 3 (NT3), and neurotrophin 4 (NT4). Moreover, the NGF antibody tanezumab has provided clinical proof of concept for inhibition of the TrkA kinase pathway in pain leading to significant interest in the development of small molecule inhibitors of TrkA. However, achieving TrkA subtype selectivity over TrkB and TrkC via a Type I and Type II inhibitor binding mode has proven challenging and Type III or Type IV allosteric inhibitors may present a more promising selectivity design approach. Furthermore, TrkA inhibitors with minimal brain availability are required to deliver an appropriate safety profile. Herein, we describe the discovery of a highly potent, subtype selective, peripherally restricted, efficacious, and well-tolerated series of allosteric TrkA inhibitors that culminated in the delivery of candidate quality compound 23.
Asunto(s)
Inhibidores de Proteínas Quinasas/química , Receptor trkA/antagonistas & inhibidores , Regulación Alostérica , Secuencia de Aminoácidos , Animales , Sitios de Unión , Cristalografía por Rayos X , Evaluación Preclínica de Medicamentos , Semivida , Ensayos Analíticos de Alto Rendimiento , Humanos , Ligandos , Microsomas Hepáticos/metabolismo , Simulación de Dinámica Molecular , Unión Proteica , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/metabolismo , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacocinética , Estructura Terciaria de Proteína , Pirazoles/síntesis química , Pirazoles/química , Pirazoles/farmacocinética , Ratas , Receptor trkA/metabolismo , Alineación de Secuencia , Relación Estructura-ActividadRESUMEN
Hormones of the neurotrophin family, nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), neurotrophin 3 (NT3), and neurotrophin 4 (NT4), are known to activate the family of Tropomyosin receptor kinases (TrkA, TrkB, and TrkC). Moreover, inhibition of the TrkA kinase pathway in pain has been clinically validated by the NGF antibody tanezumab, leading to significant interest in the development of small molecule inhibitors of TrkA. Furthermore, Trk inhibitors having an acceptable safety profile will require minimal brain availability. Herein, we discuss the discovery of two potent, selective, peripherally restricted, efficacious, and well-tolerated series of pan-Trk inhibitors which successfully delivered three candidate quality compounds 10b, 13b, and 19. All three compounds are predicted to possess low metabolic clearance in human that does not proceed via aldehyde oxidase-catalyzed reactions, thus addressing the potential clearance prediction liability associated with our current pan-Trk development candidate PF-06273340.
Asunto(s)
Descubrimiento de Drogas , Dolor/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Animales , Humanos , Ligandos , Simulación del Acoplamiento Molecular , Conformación Proteica , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacocinética , Inhibidores de Proteínas Quinasas/uso terapéutico , Piridinas/química , Piridinas/farmacocinética , Piridinas/farmacología , Piridinas/uso terapéutico , Ratas , Proteínas Tirosina Quinasas Receptoras/química , Proteínas Tirosina Quinasas Receptoras/metabolismo , Solubilidad , Relación Estructura-Actividad , Distribución TisularRESUMEN
Tumors use tryptophan-catabolizing enzymes such as indoleamine 2,3-dioxygenase (IDO-1) to induce an immunosuppressive environment. IDO-1 is induced in response to inflammatory stimuli and promotes immune tolerance through effector T-cell anergy and enhanced Treg function. As such, IDO-1 is a nexus for the induction of a key immunosuppressive mechanism and represents an important immunotherapeutic target in oncology. Starting from HTS hit 5, IDO-1 inhibitor 6 (EOS200271/PF-06840003) has been developed. The structure-activity relationship around 6 is described and rationalized using the X-ray crystal structure of 6 bound to human IDO-1, which shows that 6, differently from most of the IDO-1 inhibitors described so far, does not bind to the heme iron atom and has a novel binding mode. Clinical candidate 6 shows good potency in an IDO-1 human whole blood assay and also shows a very favorable ADME profile leading to favorable predicted human pharmacokinetic properties, including a predicted half-life of 16-19 h.
Asunto(s)
Inhibidores Enzimáticos/farmacología , Indolamina-Pirrol 2,3,-Dioxigenasa/antagonistas & inhibidores , Indoles/farmacología , Succinimidas/farmacología , Animales , Línea Celular , Cristalografía por Rayos X , Perros , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacocinética , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/química , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Indoles/química , Indoles/farmacocinética , Macaca fascicularis , Masculino , Ratones , Simulación del Acoplamiento Molecular , Ratas , Relación Estructura-Actividad , Succinimidas/química , Succinimidas/farmacocinéticaRESUMEN
The design of potent Pin1 inhibitors has been challenging because its active site specifically recognizes a phospho-protein epitope. The de novo design of phosphate-based Pin1 inhibitors focusing on the phosphate recognition pocket and the successful replacement of the phosphate group with a carboxylate have been previously reported. The potency of the carboxylate series is now further improved through structure-based optimization of ligand-protein interactions in the proline binding site which exploits the H-bond interactions necessary for Pin1 catalytic function. Further optimization using a focused library approach led to the discovery of low nanomolar non-phosphate small molecular Pin1 inhibitors. Structural modifications designed to improve cell permeability resulted in Pin1 inhibitors with low micromolar anti-proliferative activities against cancer cells.
Asunto(s)
Bencimidazoles/farmacología , Ácidos Carboxílicos/farmacología , Inhibidores Enzimáticos/farmacología , Isomerasa de Peptidilprolil/antagonistas & inhibidores , Fosfatos/química , Bencimidazoles/síntesis química , Bencimidazoles/química , Ácidos Carboxílicos/síntesis química , Ácidos Carboxílicos/química , Dominio Catalítico/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Humanos , Estructura Molecular , Peptidilprolil Isomerasa de Interacción con NIMA , Isomerasa de Peptidilprolil/metabolismo , Relación Estructura-ActividadRESUMEN
The M2 isoform of pyruvate kinase is an emerging target for antitumor therapy. In this letter, we describe the discovery of 2-((1H-benzo[d]imidazol-1-yl)methyl)-4H-pyrido[1,2-a]pyrimidin-4-ones as potent and selective PKM2 activators which were found to have a novel binding mode. The original lead identified from high throughput screening was optimized into an efficient series via computer-aided structure-based drug design. Both a representative compound from this series and an activator described in the literature were used as molecular tools to probe the biological effects of PKM2 activation on cancer cells. Our results suggested that PKM2 activation alone is not sufficient to alter cancer cell metabolism.
Asunto(s)
Bencimidazoles/química , Proteínas Portadoras/agonistas , Proteínas de la Membrana/agonistas , Pirimidinonas/química , Hormonas Tiroideas/agonistas , Sitios de Unión , Proteínas Portadoras/metabolismo , Línea Celular , Diseño Asistido por Computadora , Evaluación Preclínica de Medicamentos , Ensayos Analíticos de Alto Rendimiento , Humanos , Cinética , Proteínas de la Membrana/metabolismo , Simulación del Acoplamiento Molecular , Unión Proteica , Estructura Terciaria de Proteína , Pirimidinonas/síntesis química , Pirimidinonas/metabolismo , Relación Estructura-Actividad , Hormonas Tiroideas/metabolismo , Proteínas de Unión a Hormona TiroideRESUMEN
Lead optimization efforts that employed structure base drug design and physicochemical property based optimization leading to the discovery of a novel series of 4-methylpyrido pyrimidinone (MPP) are discussed. Synthesis and profile of 1, a PI3Kα/mTOR dual inhibitor, is highlighted.
Asunto(s)
Diseño de Fármacos , Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas/síntesis química , Piridonas/química , Pirimidinas/química , Pirimidinonas/química , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Animales , Sitios de Unión , Cristalografía por Rayos X , Semivida , Humanos , Ratones , Microsomas Hepáticos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacocinética , Estructura Terciaria de Proteína , Piridonas/síntesis química , Piridonas/farmacocinética , Pirimidinas/síntesis química , Pirimidinas/farmacocinética , Pirimidinonas/síntesis química , Pirimidinonas/farmacocinética , Pirrolidinas/química , Ratas , Relación Estructura-Actividad , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
Human glucokinase (GK) is a principal regulating sensor of plasma glucose levels. Mutations that inactivate GK are linked to diabetes, and mutations that activate it are associated with hypoglycemia. Unique kinetic properties equip GK for its regulatory role: although it has weak basal affinity for glucose, positive cooperativity in its binding of glucose causes a rapid increase in catalytic activity when plasma glucose concentrations rise above euglycemic levels. In clinical trials, small molecule GK activators (GKAs) have been efficacious in lowering plasma glucose and enhancing glucose-stimulated insulin secretion, but they carry a risk of overly activating GK and causing hypoglycemia. The theoretical models proposed to date attribute the positive cooperativity of GK to the existence of distinct protein conformations that interconvert slowly and exhibit different affinities for glucose. Here we report the respective crystal structures of the catalytic complex of GK and of a GK-glucose complex in a wide open conformation. To assess conformations of GK in solution, we also carried out small angle x-ray scattering experiments. The results showed that glucose dose-dependently converts GK from an apo conformation to an active open conformation. Compared with wild type GK, activating mutants required notably lower concentrations of glucose to be converted to the active open conformation. GKAs decreased the level of glucose required for GK activation, and different compounds demonstrated distinct activation profiles. These results lead us to propose a modified mnemonic model to explain cooperativity in GK. Our findings may offer new approaches for designing GKAs with reduced hypoglycemic risk.
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Regulación de la Expresión Génica , Glucoquinasa/metabolismo , Glucosa/química , Sitio Alostérico , Catálisis , Activación Enzimática , Homeostasis , Humanos , Hipoglucemia/patología , Cinética , Modelos Biológicos , Modelos Moleculares , Mutación , Conformación Proteica , Dispersión de Radiación , Rayos XRESUMEN
High throughput cell-based screening led to the identification of 3-aryloxy lactams as potent androgen receptor (AR) antagonists. Refinement of these leads to improve the ADME profile and remove residual agonism led to the discovery of 12, a potent full antagonist with greater oral bioavailability. Improvements in the ADME profile were realized by designing more ligand-efficient molecules with reduced molecular weights and lower lipophilicities.
Asunto(s)
Descubrimiento de Drogas , Lactamas/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Receptores Androgénicos/química , Relación Dosis-Respuesta a Droga , Ensayos Analíticos de Alto Rendimiento , Humanos , Lactamas/síntesis química , Lactamas/química , Masculino , Modelos Moleculares , Estructura Molecular , Neoplasias de la Próstata/cirugía , Receptores Androgénicos/metabolismo , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
Analogues substituted with various amines at the 6-position of the pyrazine ring on (4-amino-7-isopropyl-7H-pyrrolo[2,3-d]pyrimidin-5-yl)pyrazin-2-ylmethanone were discovered as potent and selective inhibitors of PDK1 with potential as anticancer agents. An early lead with 2-pyridine-3-ylethylamine as the pyrazine substituent showed moderate potency and selectivity. Structure-based drug design led to improved potency and selectivity against PI3Kα through a combination of cyclizing the ethylene spacer into a saturated, five-membered ring and substituting on the 4-position of the aryl ring with a fluorine. ADME properties were improved by lowering the lipophilicity with heteroatom replacements in the saturated, five-membered ring. The optimized analogues have a PDK1 Ki of 1 nM and >100-fold selectivity against PI3K/AKT-pathway kinases. The cellular potency of these analogues was assessed by the inhibition of AKT phosphorylation (T308) and by their antiproliferation activity against a number of tumor cell lines.
Asunto(s)
Antineoplásicos/síntesis química , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Piridinas/síntesis química , Pirroles/síntesis química , Proteínas Quinasas Dependientes de 3-Fosfoinosítido , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Etilaminas/síntesis química , Etilaminas/química , Etilaminas/farmacología , Humanos , Modelos Moleculares , Fosforilación , Conformación Proteica , Proteínas Proto-Oncogénicas c-akt/metabolismo , Piridinas/química , Piridinas/farmacología , Pirroles/química , Pirroles/farmacología , Transducción de Señal , Relación Estructura-ActividadRESUMEN
An aryloxy tetramethylcyclobutane was identified as a novel template for androgen receptor (AR) antagonists via cell-based high-throughput screening. Follow-up to the initial "hit" established 5 as a viable lead. Further optimization to achieve full AR antagonism led to the discovery of 26 and 30, both of which demonstrated excellent in vivo tumor growth inhibition upon oral administration in a castration-resistant prostate cancer (CRPC) animal model.
Asunto(s)
Antagonistas de Andrógenos/síntesis química , Antineoplásicos/síntesis química , Compuestos Bicíclicos Heterocíclicos con Puentes/síntesis química , Ciclobutanos/síntesis química , Pirazoles/síntesis química , Administración Oral , Antagonistas de Andrógenos/farmacocinética , Antagonistas de Andrógenos/farmacología , Andrógenos/síntesis química , Andrógenos/farmacocinética , Andrógenos/farmacología , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacocinética , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Línea Celular , Ciclobutanos/farmacocinética , Ciclobutanos/farmacología , Resistencia a Antineoplásicos , Ensayos Analíticos de Alto Rendimiento , Humanos , Ligandos , Masculino , Ratones , Ratones Desnudos , Modelos Moleculares , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Pirazoles/farmacocinética , Pirazoles/farmacología , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Phosphoinositide-dependent kinase-1 (PDK1) is a critical enzyme in the PI3K/AKT pathway and to the activation of AGC family protein kinases, including S6K, SGK, and PKC. Dysregulation of this pathway plays a key role in cancer cell growth, survival and tumor angiogenesis. As such, inhibitors of PDK1 offer the promise of a new therapeutic modality for cancer treatment. Fragment based drug screening has recently become a viable entry point for hit identification. In this work, NMR spectroscopy fragment screening of PDK1 afforded novel chemotypes as orthogonal starting points from HTS screening hits. Compounds identified as hits by NMR spectroscopy were tested in a biochemical assay, and fragments with activity in both assays were clustered. The Pfizer compound file was mined via substructure and 2D similarity search, and the chemotypes were prioritized by ligand efficiency (LE), SAR mining, chemical attractiveness, and chemical enablement of promising vectors. From this effort, an isoquinolone fragment hit, 5 (IC(50) 870 µM, LE = 0.39), was identified as a novel, ligand efficient inhibitor of PDK1 and a suitable scaffold for further optimization. Initially in the absence of crystallographic data, a fragment growing approach efficiently explored four vectors of the isoquinolone scaffold via parallel synthesis to afford a compound with crystallographic data, 16 (IC(50) 41.4 µM, LE = 0.33). Subsequent lead optimization efforts provided 24 (IC(50) 1.8 µM, LE = 0.42), with greater than fivefold selectivity against other key pathway kinases.
Asunto(s)
Descubrimiento de Drogas/métodos , Evaluación Preclínica de Medicamentos/métodos , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Sitios de Unión , Cristalografía por Rayos X , Ensayos Analíticos de Alto Rendimiento , Humanos , Enlace de Hidrógeno , Ligandos , Imagen por Resonancia Magnética , Fragmentos de Péptidos/química , Unión Proteica , Proteínas Serina-Treonina Quinasas/química , Piruvato Deshidrogenasa Quinasa Acetil-TransferidoraRESUMEN
Intra-molecular hydrogen bonding was introduced to the quinazoline motif to form a pseudo ring (intra-molecular H-bond scaffold, iMHBS) to mimic our previous published core structures, pyrido[2.3-D]pyrimidin-7-one and pteridinone, as PI3K/mTOR dual inhibitors. This design results in potent PI3K/mTOR dual inhibitors and the purposed intra-molecular hydrogen bonding structure is well supported by co-crystal structure in PI3Kγ enzyme. In addition, a novel synthetic route was developed for these analogs.
Asunto(s)
Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas/química , Quinazolinas/química , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Sitios de Unión , Línea Celular Tumoral , Cristalografía por Rayos X , Humanos , Enlace de Hidrógeno , Modelos Químicos , Modelos Moleculares , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/síntesis química , Quinazolinas/farmacología , Relación Estructura-Actividad , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
Pteridinones were designed based on a non-selective kinase template. Because of the uniqueness of the PI3K and mTOR binding pockets, a methyl group was introduced to C-4 position of the peteridinone core to give compounds with excellent selectivity for PI3K and mTOR. This series of compounds were further optimized to improve their potency against PI3Kα and mTOR. Finally, orally active compounds with improved solubility and robust in vivo efficacy in tumor growth inhibition were identified as well.
Asunto(s)
Antineoplásicos/química , Antineoplásicos/uso terapéutico , Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/uso terapéutico , Pteridinas/química , Pteridinas/uso terapéutico , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Línea Celular Tumoral , Glioma/tratamiento farmacológico , Humanos , Ratones , Modelos Moleculares , Neoplasias/tratamiento farmacológico , Fosfatidilinositol 3-Quinasas/química , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacología , Pteridinas/administración & dosificación , Pteridinas/farmacología , Solubilidad , Relación Estructura-Actividad , Serina-Treonina Quinasas TOR/química , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
A novel series of potent thioether benzenesulfonamide inhibitors of carbonic anhydrases II and IV was discovered using structure-based drug design. Synthesis, structure-activity relationship, and optimization of physicochemical properties are described. Low nanomolar potency was achieved, and selected compounds with improved thermodynamic solubility showed promising in vitro inhibition of carbonic anhydrase activity in rabbit iris ciliary body homogenate.