RESUMEN
The NLRP3 inflammasome is a component of the innate immune system involved in the production of proinflammatory cytokines. Aberrant activation by a wide range of exogenous and endogenous signals can lead to chronic, low-grade inflammation. It has attracted a great deal of interest as a drug target due to the association with diseases of large unmet medical need such as Alzheimer's disease, Parkinson's disease, arthritis, and cancer. To date, no drugs specifically targeting inhibition of the NLRP3 inflammasome have been approved. In this work, we used the known NLRP3 inflammasome inhibitor CP-456,773 (aka CRID3 or MCC 950) as our starting point and undertook a Structure-Activity Relationship (SAR) analysis and subsequent scaffold-hopping exercise. This resulted in the rational design of a series of novel ester-substituted urea compounds that are highly potent and selective NLRP3 inflammasome inhibitors, as exemplified by compounds 44 and 45. It is hypothesized that the ester moiety acts as a highly permeable delivery vehicle and is subsequently hydrolyzed to the carboxylic acid active species by carboxylesterase enzymes. These molecules are greatly differentiated from the state-of-the-art and offer potential in the treatment of NLRP3-driven diseases, particularly where tissue penetration is required.
Asunto(s)
Ésteres/farmacología , Indenos/farmacología , Inflamasomas/antagonistas & inhibidores , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Urea/análogos & derivados , Urea/farmacología , Animales , Sangre/metabolismo , Diseño de Fármacos , Estabilidad de Medicamentos , Ésteres/síntesis química , Ésteres/metabolismo , Furanos , Compuestos Heterocíclicos de 4 o más Anillos/química , Humanos , Indenos/síntesis química , Indenos/metabolismo , Ratones , Estructura Molecular , Relación Estructura-Actividad , Sulfonamidas , Sulfonas/química , Células THP-1RESUMEN
In oncology, the "Warburg effect" describes the elevated production of energy by glycolysis in cancer cells. The ubiquitous and hypoxia-induced 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) plays a noteworthy role in the regulation of glycolysis by producing fructose-2,6-biphosphate (F-2,6-BP), a potent activator of the glycolysis rate-limiting phosphofructokinase PFK-1. Series of amides and sulfonamides derivatives based on a N-aryl 6-aminoquinoxaline scaffold were synthesized and tested for their inhibition of PFKFB3 in vitro in a biochemical assay as well as in HCT116 cells. The carboxamide series displayed satisfactory kinetic solubility and metabolic stability, and within this class, potent lead compounds with low nanomolar activity have been identified with a suitable profile for further in vivo evaluation.
Asunto(s)
Amidas/química , Fosfofructoquinasa-2/antagonistas & inhibidores , Quinoxalinas/química , Quinoxalinas/farmacología , Sulfonamidas/química , Células HCT116 , Humanos , Cinética , SolubilidadRESUMEN
Maternal embryonic leucine zipper kinase (MELK) is involved in several key cellular processes and displays increased levels of expression in numerous cancer classes (colon, breast, brain, ovary, prostate and lung). Although no selective MELK inhibitors have yet been approved, increasing evidence suggest that inhibition of MELK would constitute a promising approach for cancer therapy. A weak high-throughput screening hit (17, IC50â¯≈â¯5⯵M) with lead-like properties was optimized for MELK inhibition. The early identification of a plausible binding mode by molecular modeling offered guidance in the choice of modifications towards compound 52 which displayed a 98â¯nM IC50. A good selectivity profile was achieved for a representative member of the series (29) in a 486 protein kinase panel. Future elaboration of 52 has the potential to deliver compounds for further development with chemotherapeutic aims.
Asunto(s)
Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Tiofenos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Ensayos Analíticos de Alto Rendimiento , Humanos , Concentración 50 InhibidoraRESUMEN
Energy and biomass production in cancer cells are largely supported by aerobic glycolysis in what is called the Warburg effect. The process is regulated by key enzymes, among which phosphofructokinase PFK-2 plays a significant role by producing fructose-2,6-biphosphate; the most potent activator of the glycolysis rate-limiting step performed by phosphofructokinase PFK-1. Herein, the synthesis, biological evaluation and structure-activity relationship of novel inhibitors of 6-phosphofructo-2-kinase/fructose-2,6-biphosphataseâ 3 (PFKFB3), which is the ubiquitous and hypoxia-induced isoform of PFK-2, are reported. X-ray crystallography and docking were instrumental in the design and optimisation of a series of N-aryl 6-aminoquinoxalines. The most potent representative, N-(4-methanesulfonylpyridin-3-yl)-8-(3-methyl-1-benzothiophen-5-yl)quinoxalin-6-amine, displayed an IC50 of 14â nm for the target and an IC50 of 0.49â µm for fructose-2,6-biphosphate production in human colon carcinoma HCT116 cells. This work provides a new entry in the field of PFKFB3 inhibitors with potential for development in oncology.
Asunto(s)
Descubrimiento de Drogas , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Fosfofructoquinasa-2/antagonistas & inhibidores , Quinoxalinas/química , Quinoxalinas/farmacología , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Células HCT116 , Humanos , Ácido Láctico/antagonistas & inhibidores , Ácido Láctico/biosíntesis , Modelos Moleculares , Estructura Molecular , Fosfofructoquinasa-2/metabolismo , Quinoxalinas/síntesis química , Relación Estructura-ActividadRESUMEN
In BRCA2-defective cells, poly(adenosine diphosphate [ADP]-ribose) polymerase inhibitors can trigger synthetic lethality, as two independent DNA-repairing mechanisms are simultaneously impaired. Here, we have pharmacologically induced synthetic lethality, which was triggered by combining two different small organic molecules. When administered with a BRCA2-Rad51 disruptor in nonmutant cells, Olaparib showed anticancer activity comparable to that shown when administered alone in BRCA2-defective cells. This strategy could represent an innovative approach to anticancer drug discovery and could be extended to other synthetic lethality pathways.
Asunto(s)
Proteína BRCA2/antagonistas & inhibidores , Ftalazinas/farmacología , Piperazinas/farmacología , Recombinasa Rad51/antagonistas & inhibidores , Antineoplásicos/química , Antineoplásicos/farmacología , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Línea Celular Tumoral , Reparación del ADN , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Humanos , Modelos Moleculares , Mutación , Ftalazinas/química , Piperazinas/química , Conformación Proteica , Recombinasa Rad51/metabolismoRESUMEN
Peptide-based therapeutics have grown in importance over the last few decades. Furthermore, peptides have been extensively used as lead compounds in the drug discovery process to investigate the nature of chemical space required for molecular recognition and activity at a variety of targets. This critical commentary reviews scanning techniques, which employ natural and non-proteinogenic amino acids to facilitate understanding of structural requirements for peptide biological activity. The value of sequence analysis by such methods is highlighted by examples, in which the elements for peptide affinity and activity have been elucidated and employed to prepare peptidomimetic leads for drug development.
Asunto(s)
Diseño de Fármacos , Péptidos/química , Aminoácidos/química , Compuestos Aza/química , Lactamas/química , Peptidomiméticos , Estructura Secundaria de Proteína , Relación Estructura-ActividadRESUMEN
Aryldiazepin-2-ones are known as "privileged structures", because they bind to multiple receptor types with high affinity. Toward the development of a novel class of aryldiazepin-2-one scaffolds, the synthesis of pyrrolo[3,2-e][1,4]diazepin-2-ones on a support was explored starting from N-(PhF)-4-hydroxyproline and featuring an acid-catalyzed Pictet-Spengler reaction to form the diazepine ring. Three supports [Wang resin, tetraarylphosphonium (TAP) soluble support, and Merrifield resin] were examined in the synthesis of the heterocycle and exhibited different advantages and disadvantages. Wang resin proved effective for exploratory optimization of the synthesis by identification of intermediates after resin cleavage under mild conditions; however, the acidic conditions of the Pictet-Spengler reaction caused premature loss of resin-bound material. Direct monitoring of reactions by TLC, RP-HPLC-MS, and in certain cases NMR spectroscopy was possible with the TAP support, which facilitated purification of intermediates by precipitation; however, incomplete precipitation of material led to overall yields lower than those from solid-phase approaches on resin. Merrifield resin proved stable to the conditions for the synthesis of the pyrrolo[3,2-e][1,4]diazepin-2-one targets and would be amenable to "split-and-mix" chemistry; however, relatively harsh conditions were necessary for final product cleavage. Perspective for the application of different solid-phase approaches in heterocycle library synthesis was thus obtained by demonstration of the respective utility of the three supports for preparation of pyrrolo[3,2-e][1,4]diazepin-2-one.
Asunto(s)
Azepinas/química , Azepinas/síntesis química , Pirroles/química , Pirroles/síntesis química , Acilación , Ácidos Carboxílicos/química , SolubilidadRESUMEN
The relationship between the conformation and biological activity of the peptide allosteric modulator of the interleukin-1 receptor 101.10 (D-Arg-D-Tyr-D-Thr-D-Val-D-Glu-D-Leu-D-Ala-NH2) has been studied using (R)- and (S)-Bgl residues. Twelve Bgl peptides were synthesized using (R)- and (S)-cyclic sulfamidate reagents derived from L- and D-aspartic acid in an optimized Fmoc-compatible protocol for efficient lactam installment onto the supported peptide resin. Examination of these (R)- and (S)-Bgl 101.10 analogs for their potential to inhibit IL-1ß-induced thymocyte cell proliferation using a novel fluorescence assay revealed that certain analogs exhibited retained and improved potency relative to the parent peptide 101.10. In light of previous reports that Bgl residues may stabilize type II'ß-turn-like conformations in peptides, CD spectroscopy was performed on selected compounds to identify secondary structure necessary for peptide biological activity. Results indicate that the presence of a fold about the central residues of the parent peptide may be important for activity.
Asunto(s)
Péptidos/química , Estructura Secundaria de Proteína , Receptores de Interleucina-1/química , beta-Lactamas/química , Secuencia de Aminoácidos , Dicroismo Circular , Datos de Secuencia Molecular , Estructura Molecular , Relación Estructura-ActividadRESUMEN
Incorporation of amino lactams into biologically active peptides restricts conformational mobility and may enhance selectivity and increase potency. alpha- and beta-amino gamma-lactams (Agl and Bgl), in both S and R configurations, were introduced into the growth hormone secretagogue GHRP-6 using a Fmoc-compatible solid-phase protocol relying on N-alkylation with five- and six-membered cyclic sulfamidates, followed by lactam annulation under microwave heating. Using this protocol in conjunction with IRORI Kan techniques furnished eleven new GHRP-6 analogs, and their binding affinity IC50 values on both the growth hormone secretagogue receptor 1a (GHS-R1a) and CD36 receptors are herein reported. The results indicate that selectivity towards one receptor or the other can be modulated by lactam substitution, typically at the Ala3 and the D-Phe5 positions.
Asunto(s)
Hormona del Crecimiento/metabolismo , Lactamas/química , Oligopéptidos/farmacología , Antígenos CD36/metabolismo , Hormona del Crecimiento/fisiología , Hormona de Crecimiento Humana , Resonancia Magnética Nuclear Biomolecular , Fragmentos de Péptidos/química , Conformación Proteica/efectos de los fármacos , Pliegue de Proteína , Receptores de Ghrelina/metabolismo , beta-Lactamas/químicaRESUMEN
Direct preparation of beta,beta-disubstituted C- and N-vinylindoles from condensation of aldehydes on indole derivatives is presented. Heating 1-methyl- and 1-benzylindole 3a,b with alkyl and aryl alpha-branched aldehydes and TFA in acetonitrile using microwave irradiation furnished 3-vinylindoles 1a-e in 18-76% yields. Under similar conditions, 3-substituted indoles 4a-c provided N-vinylindoles 2a-h in 16-98% yields.
RESUMEN
Incorporation of amino lactams into biologically active peptides has been commonly used to restrict conformational mobility, enhance selectivity, and increase potency. A solid-phase method using a Fmoc-protection strategy has been developed for the systematic synthesis of peptides containing configurationally defined alpha- and beta-amino gamma-lactams. N-Alkylation of N-silyl peptides with five- and six-member cyclic sulfamidates 9 and 8 minimized bis-alkylation and provided N-alkyl peptides, which underwent lactam annulation under microwave heating. Employing this solid-phase protocol on the growth hormone secretagogue GHRP-6, as well as on the allosteric modulator of the IL-1 receptor 101.10, has furnished 16 lactam derivatives and validated the effectiveness of this approach on peptides bearing aliphatic, aromatic, branched, charged, and heteroatomic side chains. The binding affinity IC(50) values of the GHRP-6 lactam analogues on both the GHS-R1a and CD36 receptors are reported as well as inhibition of thymocyte proliferation measurements for the 101.10 lactam analogues. In these cases, lactam analogues were prepared exhibiting similar or improved properties compared with the parent peptide. Considering the potential for amino lactams to induce peptide turn conformations, the effective method described herein for their supported construction on growing peptides, and for the systematical amino lactam scan of peptides, has proven useful for the rapid identification of the secondary structure necessary for peptide biological activity.