RESUMO
Cortical bone allograft sterilized with a standard γ-radiation dose of 25-35kGy has demonstrated reduced static and cyclic fracture resistance compared with unirradiated bone. To mitigate radiation damage, we recently observed a dose-dependent response of high-cycle fatigue behavior of human cortical bone from 0 to 25 kGy, with lower doses exhibiting logarithmically longer fatigue lives. The objectives of this study were as follows: (1) to determine whether fracture toughness, work-to-fracture, and fatigue crack propagation resistance of human cortical bone are also radiation dose-dependent, and (2) to determine the associations of radiation dose and a Raman biomarker for collagen disorder with fracture properties. Compact tension specimens were machined from two donor femoral pairs and allocated to four treatment groups: 0 (unirradiated control), 10, 17.5, and 25 kGy. Fracture toughness specimens were monotonically loaded to failure and the critical stress intensity factor (KC ) was determined. Work-to-fracture was calculated from the load versus displacement integral up to fracture. Fatigue crack propagation specimens were cyclically loaded under constant room-temperature irrigation and fatigue crack growth rate (da/dN) and cyclic stress intensity (∆K) were calculated. Fracture toughness, work-to-fracture, and fatigue crack propagation resistance decreased 18%, 33%, and 15-fold from 0 to 25 kGy, respectively (p < 0.05). Radiation dose was more predictive of fracture properties than collagen disorder. These findings support that quasi-static and fatigue fracture properties of cortical bone are radiation dose-dependent within this dose range. The structural alterations arising from irradiation that cause these losses in fracture resistance remain to be elucidated.
Assuntos
Osso e Ossos , Fraturas de Estresse , Humanos , Osso Cortical , Colágeno , Doses de Radiação , Estresse MecânicoRESUMO
In our pursuit of developing a novel, potent, and selective cell division cycle 7 (Cdc7) inhibitor, we optimized the previously reported thieno[3,2-d]pyrimidinone analogue I showing time-dependent Cdc7 kinase inhibition and slow dissociation kinetics. These medicinal chemistry efforts led to the identification of compound 3d, which exhibited potent cellular activity, excellent kinase selectivity, and antitumor efficacy in a COLO205 xenograft mouse model. However, the issue of formaldehyde adduct formation emerged during a detailed study of 3d, which was deemed an obstacle to further development. A structure-based approach to circumvent the adduct formation culminated in the discovery of compound 11b (TAK-931) possessing a quinuclidine moiety as a preclinical candidate. In this paper, the design, synthesis, and biological evaluation of this series of compounds will be presented.
Assuntos
Antineoplásicos/uso terapêutico , Proteínas de Ciclo Celular/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirazolonas/uso terapêutico , Pirimidinas/uso terapêutico , Pirimidinonas/uso terapêutico , Quinuclidinas/uso terapêutico , Tiofenos/uso terapêutico , Animais , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Sítios de Ligação , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Desenho de Fármacos , Descoberta de Drogas , Formaldeído/química , Humanos , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Pirazolonas/farmacologia , Pirimidinas/farmacologia , Pirimidinonas/síntese química , Pirimidinonas/metabolismo , Quinuclidinas/síntese química , Quinuclidinas/metabolismo , Relação Estrutura-Atividade , Tiofenos/síntese química , Tiofenos/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Herein we report an efficient method for the synthesis of a highly functionalized 2-pyrrolidinone, tert-butyl 3-cyano-3-cyclopropyl-2-oxopyrrolidine-4-carboxylate, from readily available starting materials. Utility of this compound was demonstrated in the synthesis of a novel series of macrocyclic Tyk2 inhibitors, leading to the identification of a potent and selective macrocyclic Tyk2 inhibitor (26).
Assuntos
Inibidores de Proteínas Quinases/síntese química , Pirrolidinonas/síntese química , TYK2 Quinase/antagonistas & inibidores , Humanos , Células Jurkat , Estrutura Molecular , Inibidores de Proteínas Quinases/farmacologia , Pirrolidinonas/farmacologia , Relação Estrutura-AtividadeRESUMO
General control nonderepressible 2 (GCN2) is a master regulator kinase of amino acid homeostasis and important for cancer survival in the tumor microenvironment under amino acid depletion. We initiated studies aiming at the discovery of novel GCN2 inhibitors as first-in-class antitumor agents and conducted modification of the substructure of sulfonamide derivatives with expected type I half binding on GCN2. Our synthetic strategy mainly corresponding to the αC-helix allosteric pocket of GCN2 led to significant enhancement in potency and a good pharmacokinetic profile in mice. In addition, compound 6d, which showed slow dissociation in binding on GCN2, demonstrated antiproliferative activity in combination with the asparagine-depleting agent asparaginase in an acute lymphoblastic leukemia (ALL) cell line, and it also displayed suppression of GCN2 pathway activation with asparaginase treatment in the ALL cell line and mouse xenograft model.
RESUMO
Retinoic-acid-related orphan receptor γt (RORγt) inverse agonists could be used for the treatment of autoimmune diseases. Previously, we reported a novel quinazolinedione 1 a with a flexible linear linker as a novel RORγt inverse agonist. A U-shaped conformation in the complex structure of 1 a with RORγt protein was confirmed. Further improvement of the pharmacokinetic (PK) profiles was required because of the low drug exposure in mice upon oral administration (mouse AUC of 1 a: 27â ng â h â mL-1 at 1â mg â kg-1 , p.o.). To improve the PK profiles, conformationally constrained U-shaped scaffolds were investigated. As a result, morpholine analogues with improved PK profiles and high potency were successfully identified. The substituent at the N1 position of the quinazoline moiety was also modified, leading to an enhancement of reporter activity. Consequently, compound 43 (N2 -(3-chloro-4-cyanophenyl)-N4 -(3-(cyclopropylmethyl)-1-isopropyl-2,4-dioxo-1,2,3,4-tetrahydroquinazolin-6-yl)morpholine-2,4-dicarboxamide) exhibited improved drug exposure (mouse AUC: 1289â ng â h â mL-1 at 1â mg â kg-1 , p.o.). In addition, suppression of IL-17A gene expression by IL-23 stimulation in a mouse pharmacodynamics model was observed for 43. The conformation of 43 with RORγt protein was also confirmed as U-shape by X-ray co-crystal structure analysis. The key interaction that boosts potency is also discussed.
Assuntos
Ciclopentanos/farmacologia , Desenho de Fármacos , Furanos/farmacologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Administração Oral , Animais , Cristalografia por Raios X , Ciclopentanos/administração & dosagem , Ciclopentanos/síntese química , Transferência Ressonante de Energia de Fluorescência , Furanos/administração & dosagem , Furanos/síntese química , Camundongos , Modelos Moleculares , Conformação Molecular , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismoRESUMO
Retinoic acid receptor-related orphan receptor γt (RORγt) agonists are expected to provide a novel class of immune-activating anticancer drugs via activation of Th17 cells and Tc17 cells. Herein, we describe a novel structure-based functionality switching approach from in house well-optimized RORγt inverse agonists to potent RORγt agonists. We succeeded in the identification of potent RORγt agonist 5 without major chemical structure change. The biochemical response was validated by molecular dynamics simulation studies that showed a helix 12 stabilization effect of RORγt agonists. These results indicate that targeting helix 12 is an attractive and novel medicinal chemistry strategy for switching existing RORγt inverse agonists to agonists.
Assuntos
Desenho de Fármacos , Agonismo Inverso de Drogas , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Animais , Ensaios de Triagem em Larga Escala , Simulação de Dinâmica Molecular , Relação Estrutura-Atividade , Células Th17/efeitos dos fármacosRESUMO
A series of tetrahydronaphthyridine derivatives as novel RORγt inverse agonists were designed and synthesized. We reduced the lipophilicity of tetrahydroisoquinoline compound 1 by replacement of the trimethylsilyl group and SBDD-guided scaffold exchange, which successfully afforded compound 7 with a lower log D value and tolerable in vitro activity. Consideration of LLE values in the subsequent optimization of the carboxylate tether led to the discovery of [ cis-3-({(5 R)-5-[(7-fluoro-1,1-dimethyl-2,3-dihydro-1 H-inden-5-yl)carbamoyl]-2-methoxy-7,8-dihydro-1,6-naphthyridin-6(5 H)-yl}carbonyl)cyclobutyl]acetic acid, TAK-828F (10), which showed potent RORγt inverse agonistic activity, excellent selectivity against other ROR isoforms and nuclear receptors, and a good pharmacokinetic profile. In animal studies, oral administration of compound 10 exhibited robust and dose-dependent inhibition of IL-17A cytokine expression in a mouse IL23-induced gene expression assay. Furthermore, development of clinical symptoms in a mouse experimental autoimmune encephalomyelitis model was significantly reduced. Compound 10 was selected as a clinical compound for the treatment of Th17-driven autoimmune diseases.
Assuntos
Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Receptores do Ácido Retinoico/agonistas , Animais , Doenças Autoimunes/tratamento farmacológico , Descoberta de Drogas , Agonismo Inverso de Drogas , Encefalomielite Autoimune Experimental/tratamento farmacológico , Expressão Gênica/efeitos dos fármacos , Genes Reporter/efeitos dos fármacos , Interleucina-17/genética , Interleucina-17/metabolismo , Subunidade p19 da Interleucina-23/genética , Subunidade p19 da Interleucina-23/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Células Th17/imunologiaRESUMO
Novel small molecules were synthesized and evaluated as retinoic acid receptor-related orphan receptor-gamma t (RORγt) inverse agonists for the treatment of inflammatory and autoimmune diseases. A hit compound, 1, was discovered by high-throughput screening of our compound library. The structure-activity relationship (SAR) study of compound 1 showed that the introduction of a chlorine group at the 3-position of 4-cyanophenyl moiety increased the potency and a 3-methylpentane-1,5-diamide linker is favorable for the activity. The carbazole moiety of 1 was also optimized; a quinazolinedione derivative 18i suppressed the increase of IL-17A mRNA level in the lymph node of a rat model of experimental autoimmune encephalomyelitis (EAE) upon oral administration. These results indicate that the novel quinazolinedione derivatives have great potential as orally available small-molecule RORγt inverse agonists for the treatment of Th17-driven autoimmune diseases. A U-shaped bioactive conformation of this chemotype with RORγt protein was also observed.
Assuntos
Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Quinazolinonas/química , Administração Oral , Animais , Sítios de Ligação , Agonismo Inverso de Drogas , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/patologia , Encefalomielite Autoimune Experimental/veterinária , Feminino , Humanos , Concentração Inibidora 50 , Interleucina-17/genética , Interleucina-17/metabolismo , Células Jurkat , Simulação de Acoplamento Molecular , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Ligação Proteica/efeitos dos fármacos , Estrutura Terciária de Proteína , Quinazolinonas/administração & dosagem , Quinazolinonas/metabolismo , Quinazolinonas/farmacologia , Ratos , Ratos Endogâmicos Lew , Solubilidade , Relação Estrutura-Atividade , Células Th17/citologia , Células Th17/efeitos dos fármacos , Células Th17/metabolismoRESUMO
A series of novel phenylglycinamides as retinoic acid receptor-related orphan receptor-gamma t (RORγt) inverse agonists were discovered through optimization of a high-throughput screen hit 1. (R)-N-(2-((3,5-Difluoro-4-(trimethylsilyl)phenyl) amino)-1-(4-methoxyphenyl)-2-oxoethyl)-3-hydroxy-N-methylisoxazole-5-carboxamide (22) was identified as one of the best of these compounds. It displayed higher subtype selectivity and specificity over other nuclear receptors and demonstrated in vivo potency to suppress the transcriptional activity of RORγt in a mouse PD (pharmacodynamic) model upon oral administration.
Assuntos
Descoberta de Drogas , Glicina/análogos & derivados , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Administração Oral , Animais , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Glicina/administração & dosagem , Glicina/química , Glicina/farmacologia , Humanos , Células Jurkat , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Modelos Moleculares , Estrutura Molecular , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Relação Estrutura-AtividadeRESUMO
It has been hypothesized that selective inhibition of phosphodiesterase (PDE) 2A could potentially be a novel approach to treat cognitive impairment in neuropsychiatric and neurodegenerative disorders through augmentation of cyclic nucleotide signaling pathways in brain regions associated with learning and memory. Following our earlier work, this article describes a drug design strategy for a new series of lead compounds structurally distinct from our clinical candidate 2 (TAK-915), and subsequent medicinal chemistry efforts to optimize potency, selectivity over other PDE families, and other preclinical properties including in vitro phototoxicity and in vivo rat plasma clearance. These efforts resulted in the discovery of N-((1S)-2-hydroxy-2-methyl-1-(4-(trifluoromethoxy)phenyl)propyl)-6-methyl-5-(3-methyl-1H-1,2,4-triazol-1-yl)pyrazolo[1,5-a]pyrimidine-3-carboxamide (20), which robustly increased 3',5'-cyclic guanosine monophosphate (cGMP) levels in the rat brain following an oral dose, and moreover, attenuated MK-801-induced episodic memory deficits in a passive avoidance task in rats. These data provide further support to the potential therapeutic utility of PDE2A inhibitors in enhancing cognitive performance.
Assuntos
Transtornos Cognitivos/tratamento farmacológico , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/antagonistas & inibidores , Descoberta de Drogas , Inibidores de Fosfodiesterase/farmacologia , Pirazinas/farmacologia , Pirazóis/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Células 3T3 , Administração Oral , Animais , Células COS , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Transtornos Cognitivos/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/metabolismo , Relação Dose-Resposta a Droga , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Estrutura Molecular , Inibidores de Fosfodiesterase/administração & dosagem , Inibidores de Fosfodiesterase/química , Difração de Pó , Pirazinas/química , Pirazóis/química , Piridinas/química , Pirimidinas/química , Ratos , Ratos Long-Evans , Solubilidade , Relação Estrutura-Atividade , TermodinâmicaRESUMO
Irregular N-methyl-D-aspartate receptor (NMDAR) function is one of the main hypotheses employed to facilitate understanding of the underlying disease state of schizophrenia. Although direct agonism of the NMDAR has not yielded promising therapeutics, advances have been made by modulating the NMDAR co-agonist site which is activated by glycine and D-serine. One approach to activate the co-agonist site is to increase synaptic D-serine levels through inhibition of D-amino acid oxidase (DAO), the major catabolic clearance pathway for this and other D-amino acids. A number of DAO inhibitors have been developed but most have not entered clinical trials. One exception to this is sodium benzoate which has demonstrated efficacy in small trials of schizophrenia and Alzheimer's disease. Herein we provide data on the effect of sodium benzoate and an optimised Takeda compound, PGM030756 on ex vivo DAO enzyme occupancy and cerebellar D-serine levels in mice. Both compounds achieve high levels of enzyme occupancy; although lower doses of PGM030756 (1, 3 and 10 mg/kg) were required to achieve this compared to sodium benzoate (300, 1000 mg/kg). Cerebellar D-serine levels were increased by both agents with a delay of approximately 6 h after dosing before the peak effect was achieved. Our data and methods may be useful in understanding the effects of sodium benzoate that have been seen in clinical trials of schizophrenia and Alzheimer's disease and to support the potential clinical assessment of other DAO inhibitors, such as PGM030756, which demonstrate good enzyme occupancy and D-serine increases following administration of low oral doses.
Assuntos
Cerebelo/metabolismo , Clorobenzenos/farmacologia , D-Aminoácido Oxidase/antagonistas & inibidores , D-Aminoácido Oxidase/metabolismo , Inibidores Enzimáticos/farmacologia , Piridazinas/farmacologia , Serina/metabolismo , Benzoato de Sódio/farmacologia , Administração Oral , Animais , Biomarcadores/metabolismo , Clorobenzenos/administração & dosagem , Clorobenzenos/química , Cristalografia por Raios X , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Piridazinas/administração & dosagem , Piridazinas/química , Benzoato de Sódio/administração & dosagem , Benzoato de Sódio/químicaRESUMO
Phosphodiesterase (PDE) 2A inhibitors have emerged as a novel mechanism with potential therapeutic option to ameliorate cognitive dysfunction in schizophrenia or Alzheimer's disease through upregulation of cyclic nucleotides in the brain and thereby achieve potentiation of cyclic nucleotide signaling pathways. This article details the expedited optimization of our recently disclosed pyrazolo[1,5-a]pyrimidine lead compound 4b, leading to the discovery of clinical candidate 36 (TAK-915), which demonstrates an appropriate combination of potency, PDE selectivity, and favorable pharmacokinetic (PK) properties, including brain penetration. Successful identification of 36 was realized through application of structure-based drug design (SBDD) to further improve potency and PDE selectivity, coupled with prospective design focused on physicochemical properties to deliver brain penetration. Oral administration of 36 demonstrated significant elevation of 3',5'-cyclic guanosine monophosphate (cGMP) levels in mouse brains and improved cognitive performance in a novel object recognition task in rats. Consequently, compound 36 was advanced into human clinical trials.
Assuntos
Encéfalo/efeitos dos fármacos , Cognição/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/antagonistas & inibidores , Inibidores de Fosfodiesterase/farmacologia , Inibidores de Fosfodiesterase/farmacocinética , Pirazinas/farmacologia , Pirazinas/farmacocinética , Animais , Encéfalo/metabolismo , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/metabolismo , Cristalografia por Raios X , GMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/metabolismo , Desenho de Fármacos , Halogenação , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Inibidores de Fosfodiesterase/química , Pirazinas/química , Pirazóis/química , Pirazóis/farmacocinética , Pirazóis/farmacologia , Pirimidinas/química , Pirimidinas/farmacocinética , Pirimidinas/farmacologia , Ratos , Ratos Sprague-DawleyRESUMO
A novel class of therapeutic drug candidates for heart failure, highly potent and selective GRK2 inhibitors, exhibit potentiation of ß-adrenergic signaling in vitro studies. Hydrazone derivative 5 and 1,2,4-triazole derivative 24a were identified as hit compounds by HTS. New scaffold generation and SAR studies of all parts resulted in a 4-methyl-1,2,4-triazole derivative with an N-benzylcarboxamide moiety with highly potent activity toward GRK2 and selectivity over other kinases. In terms of subtype selectivity, these compounds showed enough selectivity against GRK1, 5, 6, and 7 with almost equipotent inhibition to GRK3. Our medicinal chemistry efforts led to the discovery of 115h (GRK2 IC50 = 18 nM), which was obtained the cocrystal structure with human GRK2 and an inhibitor of GRK2 that potentiates ß-adrenergic receptor (ßAR)-mediated cAMP accumulation and prevents internalization of ßARs in ß2AR-expressing HEK293 cells treated with isoproterenol. Therefore, 115h appears to be a novel class of therapeutic for heart failure treatment.
Assuntos
Quinase 2 de Receptor Acoplado a Proteína G/antagonistas & inibidores , Insuficiência Cardíaca/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Triazóis/farmacologia , meta-Aminobenzoatos/farmacologia , Cristalografia por Raios X , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A/síntese química , Inibidores do Citocromo P-450 CYP3A/química , Inibidores do Citocromo P-450 CYP3A/farmacologia , Desenho de Fármacos , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Hidrazonas/síntese química , Hidrazonas/química , Hidrazonas/farmacologia , Proteína Quinase C-alfa/antagonistas & inibidores , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Piridinas/síntese química , Piridinas/química , Receptores Adrenérgicos beta/metabolismo , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química , meta-Aminobenzoatos/síntese química , meta-Aminobenzoatos/química , Quinases Associadas a rho/antagonistas & inibidoresRESUMO
Cell division cycle 7 (Cdc7) is a serine/threonine kinase that plays important roles in the regulation of DNA replication process. A genetic study indicates that Cdc7 inhibition can induce selective tumor-cell death in a p53-dependent manner, suggesting that Cdc7 is an attractive target for the treatment of cancers. In order to identify a new class of potent Cdc7 inhibitors, we generated a putative pharmacophore model based on in silico docking analysis of a known inhibitor with Cdc7 homology model. The pharmacophore model provided a minimum structural motif of Cdc7 inhibitor, by which preliminary medicinal chemistry efforts identified a dihydrothieno[3,2-d]-pyrimidin-4(1H)-one scaffold having a heteroaromatic hinge-binding moiety. The structure-activity relationship (SAR) studies resulted in the discovery of new, potent, and selective Cdc7 inhibitors 14a, c, e. Furthermore, the high selectivity of 14c, e for Cdc7 over Rho-associated protein kinase 1 (ROCK1) is discussed by utilizing a docking study with Cdc7 and ROCK2 crystal structures.
Assuntos
Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirimidinonas/farmacologia , Humanos , Modelos Moleculares , Pirimidinonas/síntese química , Pirimidinonas/química , Relação Estrutura-AtividadeRESUMO
Axl has been a target of interest in the oncology field for several years based on its role in various oncogenic processes. To date, no wild-type Axl crystal structure has been reported. Herein, we describe the structure-based optimization of a novel chemotype of Axl inhibitors, 1H-imidazole-2-carboxamide, using a mutated kinase homolog, Mer(I650M), as a crystallographic surrogate. Iterative optimization of the initial lead compound (1) led to compound (21), a selective and potent inhibitor of wild-type Axl. Compound (21) will serve as a useful compound for further in vivo studies.
Assuntos
Imidazóis/química , Imidazóis/farmacologia , Mutação , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/genética , Cristalografia por Raios X , Estrutura Molecular , c-Mer Tirosina Quinase , Receptor Tirosina Quinase AxlRESUMO
Spleen Tyrosine Kinase (SYK) is a non-receptor cytoplasmic tyrosine kinase that is primarily expressed in hematopoietic cells. SYK is a key mediator for a variety of inflammatory cells, including B cells, mast cells, macrophages and neutrophils and therefore, an attractive approach for treatment of both inflammatory diseases and oncology indications. Using in house co-crystal structure information, and structure-based drug design, we designed and optimized a novel series of heteroaromatic pyrrolidinone SYK inhibitors resulting in the selection of the development candidate TAK-659. TAK-659 is currently undergoing Phase I clinical trials for advanced solid tumor and lymphoma malignancies, a Phase Ib study in advanced solid tumors in combination with nivolumab, and PhIb/II trials for relapsed/refractory AML.
Assuntos
Descoberta de Drogas , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Pirrolidinonas/farmacologia , Quinase Syk/antagonistas & inibidores , Animais , Antineoplásicos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/química , Pirimidinas/administração & dosagem , Pirimidinas/química , Pirrolidinonas/administração & dosagem , Pirrolidinonas/química , Relação Estrutura-Atividade , Quinase Syk/metabolismoRESUMO
The crystallization experiment has one main objective: to obtain diffraction quality crystals. This can be achieved through myriad avenues; here the focus will be on crystallization in support of drug discovery. In drug discovery there are two main paradigms for crystallography: high-throughput, and by any means necessary. Each paradigm requires the investigator to formulate strategies based on different priorities. In the high-throughput environment, the emphasis is on rapid prosecution of a large number of protein targets. In the by any means necessary paradigm the target pool is generally smaller and structural information is absolutely necessary for success. The process of growing diffraction quality protein crystals involves deciding on a crystallization method, initial screening, cryoprotection, initial diffraction analysis, and growth optimization. Furthermore, in structure-based drug design it is necessary to obtain crystal structures of protein-ligand complexes.
Assuntos
Cristalização/métodos , Desenho de Fármacos , Proteínas/química , Conformação ProteicaRESUMO
Trytophan Hydroxylase Type I (TPH1), most abundantly expressed in the gastrointestinal tract, initiates the synthesis of serotonin by catalyzing hydroxylation of tryptophan in the presence of biopterin and oxygen. We have previously described three series of novel, periphery-specific TPH1 inhibitors that selectively deplete serotonin in the gastrointestinal tract. We have now determined co-crystal structures of TPH1 with three of these inhibitors at high resolution. Analysis of the structural data showed that each of the three inhibitors fills the tryptophan binding pocket of TPH1 without reaching into the binding site of the cofactor pterin, and induces major conformational changes of the enzyme. The enzyme-inhibitor complexes assume a compact conformation that is similar to the one in tryptophan complex. Kinetic analysis showed that all three inhibitors are competitive versus the substrate tryptophan, consistent with the structural data that the compounds occupy the tryptophan binding site. On the other hand, all three inhibitors appear to be uncompetitive versus the cofactor 6-methyltetrahydropterin, which is not only consistent with the structural data but also indicate that the hydroxylation reaction follows an ordered binding mechanism in which a productive complex is formed only if tryptophan binds only after pterin, similar to the kinetic mechanisms of tyrosine and phenylalanine hydroxylase.
RESUMO
A series of deoxycytidine kinase inhibitors was simultaneously optimized for potency and PK properties. A co-crystal structure then allowed merging this series with a high throughput screening hit to afford a highly potent, selective and orally bioavailable inhibitor, compound 10. This compound showed dose dependent inhibition of deoxycytidine kinase in vivo.
Assuntos
Desoxicitidina Quinase/antagonistas & inibidores , Desoxicitidina/análogos & derivados , Desenho de Fármacos , Inibidores de Proteínas Quinases/farmacologia , Desoxicitidina/síntese química , Desoxicitidina/química , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
The 2.25 A crystal structure of a complex of Aurora A kinase (AIKA) with cyclopropanecarboxylic acid-(3-(4-(3-trifluoromethyl-phenylamino)-pyrimidin-2-ylamino)-phenyl)-amide 1 is described here. The inhibitor binding mode is novel, with the cyclopropanecarboxylic acid moiety directed towards the solvent exposed region of the ATP-binding pocket, and several induced structural changes in the active-site compared with other published AIK structures. This structure provides context for the available SAR data on this compound class, and could be exploited for the design of analogs with increased affinity and selectivity for AIK.