RESUMO
Increased fructose consumption and its subsequent metabolism have been implicated in metabolic disorders such as nonalcoholic fatty liver disease and steatohepatitis (NAFLD/NASH) and insulin resistance. Ketohexokinase (KHK) converts fructose to fructose-1-phosphate (F1P) in the first step of the metabolic cascade. Herein we report the discovery of a first-in-class KHK inhibitor, PF-06835919 (8), currently in phase 2 clinical trials. The discovery of 8 was built upon our originally reported, fragment-derived lead 1 and the recognition of an alternative, rotated binding mode upon changing the ribose-pocket binding moiety from a pyrrolidinyl to an azetidinyl ring system. This new binding mode enabled efficient exploration of the vector directed at the Arg-108 residue, leading to the identification of highly potent 3-azabicyclo[3.1.0]hexane acetic acid-based KHK inhibitors by combined use of parallel medicinal chemistry and structure-based drug design.
Assuntos
Descoberta de Drogas/métodos , Inibidores Enzimáticos/química , Frutoquinases/antagonistas & inibidores , Frutoquinases/metabolismo , Frutose/efeitos adversos , Doenças Metabólicas/enzimologia , Animais , Cristalografia por Raios X , Cães , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Frutose/administração & dosagem , Hepatócitos/efeitos dos fármacos , Hepatócitos/enzimologia , Humanos , Resistência à Insulina/fisiologia , Masculino , Doenças Metabólicas/induzido quimicamente , Doenças Metabólicas/tratamento farmacológico , Estrutura Secundária de Proteína , Ratos , Ratos WistarRESUMO
We disclose the discovery and X-ray cocrystal data of potent, selective quinazoline inhibitors of PDE1. Inhibitor ( S)-3 readily attains free plasma concentrations above PDE1 IC50 values and has restricted brain access. The racemic compound 3 inhibits >75% of PDE hydrolytic activity in soluble samples of human myocardium, consistent with heightened PDE1 activity in this tissue. These compounds represent promising new tools to probe the value of PDE1 inhibition in the treatment of cardiovascular disease.
Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 1/antagonistas & inibidores , Descoberta de Drogas , Miocárdio/enzimologia , Inibidores de Fosfodiesterase/química , Inibidores de Fosfodiesterase/farmacologia , Quinazolinas/química , AMP Cíclico/metabolismo , Humanos , Modelos Moleculares , Estrutura Molecular , Conformação ProteicaRESUMO
Monoacylglycerol lipase (MAGL) inhibition provides a potential treatment approach to neuroinflammation through modulation of both the endocannabinoid pathway and arachidonoyl signaling in the central nervous system (CNS). Herein we report the discovery of compound 15 (PF-06795071), a potent and selective covalent MAGL inhibitor, featuring a novel trifluoromethyl glycol leaving group that confers significant physicochemical property improvements as compared with earlier inhibitor series with more lipophilic leaving groups. The design strategy focused on identifying an optimized leaving group that delivers MAGL potency, serine hydrolase selectivity, and CNS exposure while simultaneously reducing log D, improving solubility, and minimizing chemical lability. Compound 15 achieves excellent CNS exposure, extended 2-AG elevation effect in vivo, and decreased brain inflammatory markers in response to an inflammatory challenge.
Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/farmacologia , Carbamatos/síntese química , Carbamatos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Monoacilglicerol Lipases/antagonistas & inibidores , Neurite (Inflamação)/tratamento farmacológico , Amidoidrolases/antagonistas & inibidores , Animais , Ácidos Araquidônicos/metabolismo , Biomarcadores , Química Encefálica/efeitos dos fármacos , Cães , Desenho de Fármacos , Descoberta de Drogas , Endocanabinoides/metabolismo , Glicerídeos/metabolismo , Humanos , Macaca mulatta , Modelos Moleculares , Ratos , Ratos Wistar , Relação Estrutura-AtividadeRESUMO
Computational modeling was used to direct the synthesis of analogs of previously reported phosphodiesterase 2A (PDE2A) inhibitor 1 with an imidazotriazine core to yield compounds of significantly enhanced potency. The analog PF-05180999 (30) was subsequently identified as a preclinical candidate targeting cognitive impairment associated with schizophrenia. Compound 30 demonstrated potent binding to PDE2A in brain tissue, dose responsive mouse brain cGMP increases, and reversal of N-methyl-d-aspartate (NMDA) antagonist-induced (MK-801, ketamine) effects in electrophysiology and working memory models in rats. Preclinical pharmacokinetics revealed unbound brain/unbound plasma levels approaching unity and good oral bioavailability resulting in an average concentration at steady state (Cav,ss) predicted human dose of 30 mg once daily (q.d.). Modeling of a modified release formulation suggested that 25 mg twice daily (b.i.d.) could maintain plasma levels of 30 at or above targeted efficacious plasma levels for 24 h, which became part of the human clinical plan.
Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Animais , Disponibilidade Biológica , Encéfalo/fisiologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Humanos , Imidazóis/química , Imidazóis/metabolismo , Imidazóis/farmacocinética , Imidazóis/farmacologia , Concentração Inibidora 50 , Memória de Curto Prazo/efeitos dos fármacos , Simulação de Acoplamento Molecular , Conformação ProteicaRESUMO
Monoacylglycerol lipase (MAGL) is the main enzyme responsible for degradation of the endocannabinoid 2-arachidonoylglycerol (2-AG) in the CNS. MAGL catalyzes the conversion of 2-AG to arachidonic acid (AA), a precursor to the proinflammatory eicosannoids such as prostaglandins. Herein we describe highly efficient MAGL inhibitors, identified through a parallel medicinal chemistry approach that highlighted the improved efficiency of azetidine and piperidine-derived carbamates. The discovery and optimization of 3-substituted azetidine carbamate irreversible inhibitors of MAGL were aided by the generation of inhibitor-bound MAGL crystal structures. Compound 6, a highly efficient and selective MAGL inhibitor against recombinant enzyme and in a cellular context, was tested in vivo and shown to elevate central 2-AG levels at a 10 mg/kg dose.
Assuntos
Azetidinas/farmacologia , Carbamatos/farmacologia , Inibidores Enzimáticos/farmacologia , Monoacilglicerol Lipases/antagonistas & inibidores , Piperidinas/farmacologia , Animais , Azetidinas/química , Azetidinas/farmacocinética , Carbamatos/química , Carbamatos/farmacocinética , Linhagem Celular , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Humanos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Monoacilglicerol Lipases/metabolismo , Piperidinas/química , Piperidinas/farmacocinética , Proteínas Recombinantes/metabolismoRESUMO
Increased fructose consumption and its subsequent metabolism have been implicated in hepatic steatosis, dyslipidemia, obesity, and insulin resistance in humans. Since ketohexokinase (KHK) is the principal enzyme responsible for fructose metabolism, identification of a selective KHK inhibitor may help to further elucidate the effect of KHK inhibition on these metabolic disorders. Until now, studies on KHK inhibition with small molecules have been limited due to the lack of viable in vivo pharmacological tools. Herein we report the discovery of 12, a selective KHK inhibitor with potency and properties suitable for evaluating KHK inhibition in rat models. Key structural features interacting with KHK were discovered through fragment-based screening and subsequent optimization using structure-based drug design, and parallel medicinal chemistry led to the identification of pyridine 12.
Assuntos
Desenho de Fármacos , Frutoquinases/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Cristalografia por Raios X , Frutoquinases/química , Frutoquinases/metabolismo , Humanos , Masculino , Simulação de Acoplamento Molecular , Piridinas/química , Piridinas/farmacologia , Ratos , Ratos Sprague-DawleyRESUMO
Phosphodiesterase 2A (PDE2A) inhibitors have been reported to demonstrate in vivo activity in preclinical models of cognition. To more fully explore the biology of PDE2A inhibition, we sought to identify potent PDE2A inhibitors with improved brain penetration as compared to current literature compounds. Applying estimated human dose calculations while simultaneously leveraging synthetically enabled chemistry and structure-based drug design has resulted in a highly potent, selective, brain penetrant compound 71 (PF-05085727) that effects in vivo biochemical changes commensurate with PDE2A inhibition along with behavioral and electrophysiological reversal of the effects of NMDA antagonists in rodents. This data supports the ability of PDE2A inhibitors to potentiate NMDA signaling and their further development for clinical cognition indications.
Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/antagonistas & inibidores , Desenho de Fármacos , Inibidores de Fosfodiesterase/química , Inibidores de Fosfodiesterase/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cristalografia por Raios X , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/metabolismo , Cães , Haplorrinos , Humanos , Camundongos , Simulação de Acoplamento Molecular , Inibidores de Fosfodiesterase/administração & dosagem , Inibidores de Fosfodiesterase/farmacocinética , RatosRESUMO
The tubulysin class of natural products has attracted much attention from the medicinal chemistry community due to its potent cytotoxicity against a wide range of human cancer cell lines, including significant activity in multidrug-resistant carcinoma models. As a result of their potency, the tubulysins have become an important tool for use in targeted therapy, being widely pursued as payloads in the development of novel small molecule drug conjugates (SMDCs) and antibody-drug conjugates (ADCs). A structure-based and parallel medicinal chemistry approach was applied to the synthesis of novel tubulysin analogues. These efforts led to the discovery of a number of novel and potent cytotoxic tubulysin analogues, providing a framework for our simultaneous report, which highlights the discovery of tubulysin-based ADCs, including use of site-specific conjugation to address in vivo stability of the C-11 acetate functionality.
RESUMO
Lysophospholipase-like 1 (LYPLAL1) is an uncharacterized metabolic serine hydrolase. Human genome-wide association studies link variants of the gene encoding this enzyme to fat distribution, waist-to-hip ratio, and nonalcoholic fatty liver disease. We describe the discovery of potent and selective covalent small-molecule inhibitors of LYPLAL1 and their use to investigate its role in hepatic metabolism. In hepatocytes, selective inhibition of LYPLAL1 increased glucose production supporting the inference that LYPLAL1 is a significant actor in hepatic metabolism. The results provide an example of how a selective chemical tool can contribute to evaluating a hypothetical target for therapeutic intervention, even in the absence of complete biochemical characterization.
Assuntos
Hidrolases/metabolismo , Lisofosfolipase/antagonistas & inibidores , Serina/metabolismo , Animais , Cristalização , Cristalografia por Raios X , Inibidores Enzimáticos/farmacologia , Humanos , Lisofosfolipase/químicaRESUMO
N-methyl-d-aspartate receptors (NMDARs) are glutamate-gated ion channels that play key roles in brain physiology and pathology. Because numerous pathologic conditions involve NMDAR overactivation, subunit-selective antagonists hold strong therapeutic potential, although clinical successes remain limited. Among the most promising NMDAR-targeting drugs are allosteric inhibitors of GluN2B-containing receptors. Since the discovery of ifenprodil, a range of GluN2B-selective compounds with strikingly different structural motifs have been identified. This molecular diversity raises the possibility of distinct binding sites, although supporting data are lacking. Using X-ray crystallography, we show that EVT-101, a GluN2B antagonist structurally unrelated to the classic phenylethanolamine pharmacophore, binds at the same GluN1/GluN2B dimer interface as ifenprodil but adopts a remarkably different binding mode involving a distinct subcavity and receptor interactions. Mutagenesis experiments demonstrate that this novel binding site is physiologically relevant. Moreover, in silico docking unveils that GluN2B-selective antagonists broadly divide into two distinct classes according to binding pose. These data widen the allosteric and pharmacological landscape of NMDARs and offer a renewed structural framework for designing next-generation GluN2B antagonists with therapeutic value for brain disorders.
Assuntos
Antagonistas Adrenérgicos alfa/metabolismo , Drogas em Investigação/metabolismo , Moduladores de Transporte de Membrana/metabolismo , Modelos Moleculares , Receptores de N-Metil-D-Aspartato/metabolismo , Antagonistas Adrenérgicos alfa/química , Antagonistas Adrenérgicos alfa/farmacologia , Regulação Alostérica/efeitos dos fármacos , Substituição de Aminoácidos , Animais , Sítios de Ligação , Biologia Computacional , Drogas em Investigação/química , Drogas em Investigação/farmacologia , Sistemas Inteligentes , Humanos , Imidazóis/química , Imidazóis/metabolismo , Imidazóis/farmacologia , Ligantes , Moduladores de Transporte de Membrana/química , Moduladores de Transporte de Membrana/farmacologia , Conformação Molecular , Simulação de Acoplamento Molecular , Mutação , Oxidiazóis/química , Oxidiazóis/metabolismo , Oxidiazóis/farmacologia , Piperidinas/química , Piperidinas/metabolismo , Piperidinas/farmacologia , Domínios e Motivos de Interação entre Proteínas , Subunidades Proteicas/antagonistas & inibidores , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Piridazinas/química , Piridazinas/metabolismo , Piridazinas/farmacologia , Pirimidinas/química , Pirimidinas/metabolismo , Pirimidinas/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Proteínas de Xenopus/antagonistas & inibidores , Proteínas de Xenopus/química , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismoRESUMO
A unique tetrahydrofuran ether class of highly potent α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor potentiators has been identified using rational and structure-based drug design. An acyclic lead compound, containing an ether-linked isopropylsulfonamide and biphenyl group, was pharmacologically augmented by converting it to a conformationally constrained tetrahydrofuran to improve key interactions with the human GluA2 ligand-binding domain. Subsequent replacement of the distal phenyl motif with 2-cyanothiophene to enhance its potency, selectivity, and metabolic stability afforded N-{(3S,4S)-4-[4-(5-cyano-2-thienyl)phenoxy]tetrahydrofuran-3-yl}propane-2-sulfonamide (PF-04958242, 3), whose preclinical characterization suggests an adequate therapeutic index, aided by low projected human oral pharmacokinetic variability, for clinical studies exploring its ability to attenuate cognitive deficits in patients with schizophrenia.
Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Receptores de AMPA/metabolismo , Sulfonamidas/farmacologia , Tiofenos/farmacologia , Administração Oral , Adolescente , Adulto , Idoso , Animais , Sítios de Ligação , Modelos Animais de Doenças , Cães , Relação Dose-Resposta a Droga , Descoberta de Drogas , Estabilidade de Medicamentos , Feminino , Humanos , Masculino , Memória de Curto Prazo/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Conformação Proteica , Ratos Sprague-Dawley , Esquizofrenia/tratamento farmacológico , Relação Estrutura-Atividade , Sulfonamidas/química , Tiofenos/química , Adulto JovemRESUMO
In recent years, the first generation of ß-secretase (BACE1) inhibitors advanced into clinical development for the treatment of Alzheimer's disease (AD). However, the alignment of drug-like properties and selectivity remains a major challenge. Herein, we describe the discovery of a novel class of potent, low clearance, CNS penetrant BACE1 inhibitors represented by thioamidine 5. Further profiling suggested that a high fraction of the metabolism (>95%) was due to CYP2D6, increasing the potential risk for victim-based drug-drug interactions (DDI) and variable exposure in the clinic due to the polymorphic nature of this enzyme. To guide future design, we solved crystal structures of CYP2D6 complexes with substrate 5 and its corresponding metabolic product pyrazole 6, which provided insight into the binding mode and movements between substrate/inhibitor complexes. Guided by the BACE1 and CYP2D6 crystal structures, we designed and synthesized analogues with reduced risk for DDI, central efficacy, and improved hERG therapeutic margins.
Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Secretases da Proteína Precursora do Amiloide/química , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Ácido Aspártico Endopeptidases/química , Citocromo P-450 CYP2D6/química , Interações Medicamentosas , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Sequência de Aminoácidos , Proteínas Amiloidogênicas/metabolismo , Animais , Cristalografia por Raios X , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Desenho de Fármacos , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Canais de Potássio Éter-A-Go-Go/metabolismo , Humanos , Concentração Inibidora 50 , Masculino , Camundongos Endogâmicos , Modelos Moleculares , Dados de Sequência Molecular , Inibidores de Proteases/administração & dosagem , Inibidores de Proteases/farmacocinética , Pirazóis/química , Relação Estrutura-AtividadeRESUMO
Phosphodiesterase 4 (PDE4) is an essential contributor to intracellular signaling and an important drug target. The four members of this enzyme family (PDE4A to -D) are functional dimers in which each subunit contains two upstream conserved regions (UCR), UCR1 and -2, which precede the C-terminal catalytic domain. Alternative promoters, transcriptional start sites, and mRNA splicing lead to the existence of over 25 variants of PDE4, broadly classified as long, short, and supershort forms. We report the X-ray crystal structure of long form PDE4B containing UCR1, UCR2, and the catalytic domain, crystallized as a dimer in which a disulfide bond cross-links cysteines engineered into UCR2 and the catalytic domain. Biochemical and mass spectrometric analyses showed that the UCR2-catalytic domain interaction occurs in trans, and established that this interaction regulates the catalytic activity of PDE4. By elucidating the key structural determinants of dimerization, we show that only long forms of PDE4 can be regulated by this mechanism. The results also provide a structural basis for the long-standing observation of high- and low-affinity binding sites for the prototypic inhibitor rolipram.
Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Engenharia de Proteínas/métodos , Processamento Alternativo , Domínio Catalítico , Cromatografia Líquida , Códon , Cristalografia por Raios X , AMP Cíclico/metabolismo , Disostoses/enzimologia , Regulação Enzimológica da Expressão Gênica , Variação Genética , Humanos , Deficiência Intelectual/enzimologia , Espectrometria de Massas , Modelos Moleculares , Mutação , Osteocondrodisplasias/enzimologia , Fosforilação , Conformação Proteica , Multimerização Proteica , Rolipram/química , Transdução de Sinais , Difração de Raios XRESUMO
Auristatins, synthetic analogues of the antineoplastic natural product Dolastatin 10, are ultrapotent cytotoxic microtubule inhibitors that are clinically used as payloads in antibody-drug conjugates (ADCs). The design and synthesis of several new auristatin analogues with N-terminal modifications that include amino acids with α,α-disubstituted carbon atoms are described, including the discovery of our lead auristatin, PF-06380101. This modification of the peptide structure is unprecedented and led to analogues with excellent potencies in tumor cell proliferation assays and differential ADME properties when compared to other synthetic auristatin analogues that are used in the preparation of ADCs. In addition, auristatin cocrystal structures with tubulin are being presented that allow for the detailed examination of their binding modes. A surprising finding is that all analyzed analogues have a cis-configuration at the Val-Dil amide bond in their functionally relevant tubulin bound state, whereas in solution this bond is exclusively in the trans-configuration. This remarkable observation shines light onto the preferred binding mode of auristatins and serves as a valuable tool for structure-based drug design.
Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Depsipeptídeos/química , Depsipeptídeos/farmacologia , Descoberta de Drogas , Neoplasias/tratamento farmacológico , Animais , Área Sob a Curva , Células Cultivadas , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Modelos Moleculares , Estrutura Molecular , Conformação Proteica , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Espectrometria de Massas em Tandem , Tubulina (Proteína)/metabolismoRESUMO
Positive allosteric modulators ("potentiators") of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors (AMPAR) enhance excitatory neurotransmission and may improve the cognitive deficits associated with various neurological disorders. The dihydroisoxazole (DHI) series of AMPAR potentiators described herein originated from the identification of 7 by a high-throughput functional activity screen using mouse embryonic stem (mES) cell-derived neuronal precursors. Subsequent structure-based drug design using X-ray crystal structures of the ligand-binding domain of human GluA2 led to the discovery of both PF-04725379 (11), which in tritiated form became a novel ligand for characterizing the binding affinities of subsequent AMPAR potentiators in rat brain homogenate, and PF-04701475 (8a), a prototype used to explore AMPAR-mediated pharmacology in vivo. Lead series optimization provided 16a, a functionally potent compound lacking the potentially bioactivatable aniline within 8a, but retaining desirable in vitro ADME properties.
Assuntos
Descoberta de Drogas , Isoxazóis/química , Isoxazóis/farmacologia , Receptores de AMPA/metabolismo , Absorção , Regulação Alostérica/efeitos dos fármacos , Animais , Ensaios de Triagem em Larga Escala , Humanos , Isoxazóis/metabolismo , Isoxazóis/farmacocinética , Masculino , Camundongos , Modelos Moleculares , Estrutura Terciária de Proteína , Ratos , Receptores de AMPA/química , Relação Estrutura-AtividadeRESUMO
We identified potent, selective PDE2 inhibitors by optimizing residual PDE2 activity in a series of PDE4 inhibitors, while simultaneously minimizing PDE4 activity. These newly designed PDE2 inhibitors bind to the PDE2 enzyme in a cGMP-like mode in contrast to the cAMP-like binding mode found in PDE4. Structure activity relationship studies coupled with an inhibitor bound crystal structure in the active site of the catalytic domain of PDE2 identified structural features required to minimize PDE4 inhibition while simultaneously maximizing PDE2 inhibition.
Assuntos
Azirinas/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/antagonistas & inibidores , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/química , Di-Hidropiridinas/química , Inibidores da Fosfodiesterase 4/química , Inibidores de Fosfodiesterase/química , Animais , Azirinas/metabolismo , Azirinas/uso terapêutico , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Di-Hidropiridinas/metabolismo , Di-Hidropiridinas/uso terapêutico , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Osteoartrite/tratamento farmacológico , Inibidores de Fosfodiesterase/metabolismo , Inibidores de Fosfodiesterase/uso terapêutico , Ligação Proteica , Relação Estrutura-AtividadeRESUMO
Selective phosphodiesterase 2 (PDE2) inhibitors are shown to have efficacy in a rat model of osteoarthritis (OA) pain. We identified potent, selective PDE2 inhibitors by optimizing residual PDE2 activity in a series of phosphodiesterase 4 (PDE4) inhibitors, while minimizing PDE4 inhibitory activity. These newly designed PDE2 inhibitors bind to the PDE2 enzyme in a cGMP-like binding mode orthogonal to the cAMP-like binding mode found in PDE4. Extensive structure activity relationship studies ultimately led to identification of pyrazolodiazepinone, 22, which was >1000-fold selective for PDE2 over recombinant, full length PDEs 1B, 3A, 3B, 4A, 4B, 4C, 7A, 7B, 8A, 8B, 9, 10 and 11. Compound 22 also retained excellent PDE2 selectivity (241-fold to 419-fold) over the remaining recombinant, full length PDEs, 1A, 4D, 5, and 6. Compound 22 exhibited good pharmacokinetic properties and excellent oral bioavailability (F=78%, rat). In an in vivo rat model of OA pain, compound 22 had significant analgesic activity 1 and 3h after a single, 10 mg/kg, subcutaneous dose.
Assuntos
Azepinas/química , Azirinas/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/antagonistas & inibidores , Di-Hidropiridinas/química , Inibidores de Fosfodiesterase/química , Pirazóis/química , Analgésicos/química , Analgésicos/farmacocinética , Analgésicos/uso terapêutico , Animais , Azepinas/farmacocinética , Azepinas/uso terapêutico , Azirinas/farmacocinética , Azirinas/uso terapêutico , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Nucleotídeo Cíclico Fosfodiesterase do Tipo 2/metabolismo , Di-Hidropiridinas/farmacocinética , Di-Hidropiridinas/uso terapêutico , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Meia-Vida , Osteoartrite/tratamento farmacológico , Inibidores da Fosfodiesterase 4/química , Inibidores de Fosfodiesterase/farmacocinética , Inibidores de Fosfodiesterase/uso terapêutico , Ligação Proteica , Pirazóis/farmacocinética , Pirazóis/uso terapêutico , Ratos , Relação Estrutura-AtividadeRESUMO
The structure-based design, synthesis, and biological evaluation of a new pyrazole series of irreversible KAT II inhibitors are described herein. The modification of the inhibitor scaffold of 1 and 2 from a dihydroquinolinone core to a tetrahydropyrazolopyridinone core led to discovery of a new series of potent KAT II inhibitors with excellent physicochemical properties. Compound 20 is the most potent and lipophilically efficient of these new pyrazole analogs, with a k(inact)/K(i) value of 112,000 M(-1)s(-1) and lipophilic efficiency (LipE) of 8.53. The X-ray crystal structure of 20 with KAT II demonstrates key features that contribute to this remarkable potency and binding efficiency.
Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Pirazóis/farmacologia , Transaminases/antagonistas & inibidores , Domínio Catalítico/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Modelos Moleculares , Estrutura Molecular , Pirazóis/síntese química , Pirazóis/química , Relação Estrutura-Atividade , Transaminases/metabolismoRESUMO
Schizophrenia is a highly debilitating mental disorder which afflicts approximately 1% of the global population. Cognitive and negative deficits account for the lifelong disability associated with schizophrenia, whose symptoms are not effectively addressed by current treatments. New medicines are needed to treat these aspects of the disease. Neurodevelopmental, neuropathological, genetic, and behavioral pharmacological data indicate that schizophrenia stems from a dysfunction of glutamate synaptic transmission, particularly in frontal cortical networks. A number of novel pre- and postsynaptic mechanisms affecting glutamatergic synaptic transmission have emerged as viable targets for schizophrenia. While developing orthosteric glutamatergic agents for these targets has proven extremely difficult, targeting allosteric sites of these targets has emerged as a promising alternative. From a medicinal chemistry perspective, allosteric sites provide an opportunity of finding agents with better drug-like properties and greater target specificity. Furthermore, allosteric modulators are better suited to maintaining the highly precise temporal and spatial aspects of glutamatergic synaptic transmission. Herein, we review neuropathological and genomic/genetic evidence underscoring the importance of glutamate synaptic dysfunction in the etiology of schizophrenia and make a case for allosteric targets for therapeutic intervention. We review progress in identifying allosteric modulators of AMPA receptors, NMDA receptors, and metabotropic glutamate receptors, all with the aim of restoring physiological glutamatergic synaptic transmission. Challenges remain given the complexity of schizophrenia and the difficulty in studying cognition in animals and humans. Nonetheless, important compounds have emerged from these efforts and promising preclinical and variable clinical validation has been achieved.