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1.
PLoS One ; 19(9): e0308389, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39236043

RESUMEN

Micro and nanoscale patterning of surface features and biochemical cues have emerged as tools to precisely direct neurite growth into close proximity with next generation neural prosthesis electrodes. Biophysical cues can exert greater influence on neurite pathfinding compared to the more well studied biochemical cues; yet the signaling events underlying the ability of growth cones to respond to these microfeatures remain obscure. Intracellular Ca2+ signaling plays a critical role in how a growth cone senses and grows in response to various cues (biophysical features, repulsive peptides, chemo-attractive gradients). Here, we investigate the role of inositol triphosphate (IP3) and ryanodine-sensitive receptor (RyR) signaling as sensory neurons (spiral ganglion neurons, SGNs, and dorsal root ganglion neurons, DRGNs) pathfind in response to micropatterned substrates of varied geometries. We find that IP3 and RyR signaling act in the growth cone as they navigate biophysical cues and enable proper guidance to biophysical, chemo-permissive, and chemo-repulsive micropatterns. In response to complex micropatterned geometries, RyR signaling appears to halt growth in response to both topographical features and chemo-repulsive cues. IP3 signaling appears to play a more complex role, as growth cones appear to sense the microfeatures in the presence of xestospongin C but are unable to coordinate turning in response to them. Overall, key Ca2+ signaling elements, IP3 and RyR, are found to be essential for SGNs to pathfind in response to engineered biophysical and biochemical cues. These findings inform efforts to precisely guide neurite regeneration for improved neural prosthesis function, including cochlear implants.


Asunto(s)
Neuritas , Canal Liberador de Calcio Receptor de Rianodina , Transducción de Señal , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Neuritas/metabolismo , Animales , Ganglios Espinales/metabolismo , Ganglios Espinales/citología , Conos de Crecimiento/metabolismo , Conos de Crecimiento/efectos de los fármacos , Señalización del Calcio , Ratas , Propiedades de Superficie , Células Cultivadas , Oxazoles , Compuestos Macrocíclicos
2.
J Am Chem Soc ; 146(34): 24053-24060, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39136646

RESUMEN

Macrocyclic peptides are promising scaffolds for the covalent ligand discovery. However, platforms enabling the direct identification of covalent macrocyclic ligands in a high-throughput manner are limited. In this study, we present an mRNA display platform allowing selection of covalent macrocyclic inhibitors using 1,3-dibromoacetone-vinyl sulfone (DBA-VS). Testcase selections on TEV protease resulted in potent covalent inhibitors with diverse cyclic structures, among which cTEV6-2, a macrocyclic peptide with a unique C-terminal cyclization, emerged as the most potent covalent inhibitor of TEV protease described to-date. This study outlines the workflow for integrating chemical functionalization─installation of a covalent warhead─with mRNA display and showcases its application in targeted covalent ligand discovery.


Asunto(s)
ARN Mensajero , ARN Mensajero/antagonistas & inhibidores , Ciclización , Sulfuros/química , Sulfuros/farmacología , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacología , Péptidos Cíclicos/síntesis química , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/farmacología , Compuestos Macrocíclicos/síntesis química , Sulfonas/química , Sulfonas/farmacología , Descubrimiento de Drogas , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/química , Inhibidores de Proteasas/síntesis química , Estructura Molecular
3.
Chem Commun (Camb) ; 60(70): 9436-9439, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39139063

RESUMEN

Oxidation of a thioether linkage in thioether-closed macrocyclic peptides led to collision-induced site-selective linearization of the peptides. This method has allowed for de novo sequencing of thioether macrocyclic peptides. The utility of the sequencing method was demonstrated by identifying the correct peptide sequences from a virtually randomized thioether macrocyclic peptide library.


Asunto(s)
Oxidación-Reducción , Sulfuros , Sulfuros/química , Péptidos Cíclicos/química , Compuestos Macrocíclicos/química , Péptidos/química , Análisis de Secuencia de Proteína , Biblioteca de Péptidos , Secuencia de Aminoácidos
4.
Nat Commun ; 15(1): 7151, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39169043

RESUMEN

Separations are core processes in the chemical and pharmaceutical industries. Several steps of fractionation and purification of multicomponent mixtures are required. Membrane technology can operate at fair temperatures, saving energy and processing sensitive compounds. However, breakthroughs require high stability and selectivity beyond those available today. Here, we propose membranes constituted by fully crosslinked crown ethers using interfacial polymerization. The 24 nm-thick nanofilms on robust porous supports exhibit up to 90% higher selectivity than commercially available membranes, with a 90% increase in solvent permeance. The membranes are tested with a complex mixture of structurally diverse solutes containing active pharmaceutical ingredients. The membranes are effective for the total retention and concentration of active pharmaceutical ingredients with molecular weights around 800 g mol-1. The ability to distinguish between smaller molecules in the range between 100 and 370 g mol-1 is confirmed with high separation factors, which could provide a significant advance for the pharmaceutical industry.


Asunto(s)
Membranas Artificiales , Solventes , Solventes/química , Preparaciones Farmacéuticas/química , Preparaciones Farmacéuticas/aislamiento & purificación , Porosidad , Éteres Corona/química , Compuestos Macrocíclicos/química , Polimerizacion , Peso Molecular
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 323: 124906, 2024 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-39111032

RESUMEN

A novel CB[6]-based supramolecular assembly [K(ANS)(CB[6])2(DMF)2(H2O)0.5] (1) (CB[6] = cucurbit[6]uril, ANS- = 8-amino-1-naphthalene sulfonic acid ion) was successfully synthesized under solvothermal condition. Performance studies have shown that 1 exhibited excellent chemical stability and recycling performance. Meanwhile, 1 exhibited remarkable potential as a fluorescence sensor for the detection of 2,4,6-trinitrophenol (TNP), 4-nitrophenol (4-NP), and rifampicin (RFP) in both aqueous environments and practical samples. This sensing capability is achieved through fluorescence quenching, which offers fast response times and exceptional sensitivity, with detection limits of 0.19 µM for both TNP and 4-NP, and 0.21 µM for RFP. Even more remarkably, an anti-counterfeiting ink based on 1 and a portable test hydrogel were devised for encrypting information and visually detecting using a smartphone application. This work has the potential to expand the utilization of CB[6]-based materials in optical applications.


Asunto(s)
Antibacterianos , Hidrocarburos Aromáticos con Puentes , Imidazoles , Espectrometría de Fluorescencia , Hidrocarburos Aromáticos con Puentes/química , Espectrometría de Fluorescencia/métodos , Imidazoles/química , Antibacterianos/análisis , Antibacterianos/química , Nitrocompuestos/análisis , Nitrocompuestos/química , Límite de Detección , Colorantes Fluorescentes/química , Compuestos Heterocíclicos con 2 Anillos , Compuestos Macrocíclicos , Imidazolidinas
6.
Bioorg Med Chem ; 111: 117846, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39106653

RESUMEN

The coronavirus disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been spread worldwide for more than 3 years. Although the hospitalization rate and mortality have decreased dramatically due to wide vaccination effort and improved treatment options, the disease is still a global health issue due to constant viral mutations, causing negative impact on social and economic activities. In addition, long COVID and complications arising from COVID-19 weeks after infection have become a concern for public health experts. Therefore, better treatments for COVID-19 are still needed. Herein, we describe a class of macrocyclic peptidomimetic compounds that are potent inhibitors of SARS-Cov-2 3CL protease (3CLpro). Significantly, some of the compounds showed a higher stability against human liver microsomes (HLM t1/2 > 180 min) and may be suitable for oral administration without the need for a pharmacokinetic (PK) boosting agent such as ritonavir.


Asunto(s)
Antivirales , Proteasas 3C de Coronavirus , Compuestos Macrocíclicos , SARS-CoV-2 , Proteasas 3C de Coronavirus/antagonistas & inhibidores , Proteasas 3C de Coronavirus/metabolismo , Humanos , SARS-CoV-2/efectos de los fármacos , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/farmacología , Compuestos Macrocíclicos/síntesis química , Compuestos Macrocíclicos/farmacocinética , Antivirales/farmacología , Antivirales/química , Antivirales/síntesis química , Antivirales/farmacocinética , Microsomas Hepáticos/metabolismo , Peptidomiméticos/farmacología , Peptidomiméticos/química , Peptidomiméticos/síntesis química , Descubrimiento de Drogas , Tratamiento Farmacológico de COVID-19 , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/química , Inhibidores de Proteasas/síntesis química , Inhibidores de Proteasas/farmacocinética , Relación Estructura-Actividad
7.
J Chromatogr A ; 1732: 465231, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39133951

RESUMEN

Macrocycles play vital roles in supramolecular chemistry and chromatography. 1,1'-Bi-2-naphthol (BINOL)-based chiral polyimine macrocycles are an emerging class of chiral macrocycles that can be constructed by one-step aldehyde-amine condensation of BINOL derivatives with other building blocks. These macrocycles exhibit good characteristics, such as facile preparation, rigid cyclic structures, multiple chiral centers, and defined molecular cavities, that make them good candidates as new chiral recognition materials for chromatographic enantioseparations. In this study, a BINOL-based [2+2] chiral polyimine macrocycle was synthesized by one-step condensation of enantiopure (S)-2,2'-dihydroxy-[1,1'-binaphthalene]-3,3'-dicarboxaldehyde with (1R,2R)-1,2-diaminocyclohexane. The product was modified with 5-bromo-1-pentene and then attached to thiolated silica using click chemistry to construct a new chiral stationary phase (CSP). The enantioselectivity of the new CSP was explored by separating various racemates under normal phase (NP) and reversed phase (RP) high performance liquid chromatography (HPLC). Thirteen racemates and eight racemates were enantioseparated under the two separation modes, respectively, including chiral alcohols, phenols, esters, ketones, amines, and organic acids. Among them, nine racemates achieved baseline separation under NP-HPLC and seven racemates achieved baseline separation under RP-HPLC. High resolution separation was observed with benzoin (Rs = 5.10), epinephrine (Rs = 4.98), 3-benzyloxy-1,2-propanediol (Rs = 4.42), and 4,4'-dimethylbenzoin (Rs = 4.52) in NP-HPLC, and with 4-methylbenzhydrol (Rs = 4.72), benzoin ethyl ether (Rs = 3.79), 1-phenyl-1-pentanol (Rs = 3.68), and 1-(3-bromophenyl)ethanol (Rs = 3.60) in RP-HPLC. Interestingly, the CSP complemented Chiralcel OD-H, Chiralpak AD-H, and CYCLOBOND I 2000 RSP columns for resolution of these test racemates, separating several racemic compounds that could not be well separated by the three commercially available columns. The influences of injected sample amount on separation were also evaluated. It was found that the column exhibited excellent stability and reproducibility after hundreds of injections, and the relative standard deviations (n = 5) of the retention time and resolution were less than 0.49% and 0.69%, respectively. This study indicates that the BINOL-based chiral macrocycle has great potential for HPLC enantioseparation.


Asunto(s)
Compuestos Macrocíclicos , Naftoles , Dióxido de Silicio , Cromatografía Líquida de Alta Presión/métodos , Estereoisomerismo , Naftoles/química , Naftoles/aislamiento & purificación , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/aislamiento & purificación , Dióxido de Silicio/química
8.
Sci Data ; 11(1): 859, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39122750

RESUMEN

Computational and machine learning approaches to model the conformational landscape of macrocyclic peptides have the potential to enable rational design and optimization. However, accurate, fast, and scalable methods for modeling macrocycle geometries remain elusive. Recent deep learning approaches have significantly accelerated protein structure prediction and the generation of small-molecule conformational ensembles, yet similar progress has not been made for macrocyclic peptides due to their unique properties. Here, we introduce CREMP, a resource generated for the rapid development and evaluation of machine learning models for macrocyclic peptides. CREMP contains 36,198 unique macrocyclic peptides and their high-quality structural ensembles generated using the Conformer-Rotamer Ensemble Sampling Tool (CREST). Altogether, this new dataset contains nearly 31.3 million unique macrocycle geometries, each annotated with energies derived from semi-empirical extended tight-binding (xTB) DFT calculations. Additionally, we include 3,258 macrocycles with reported passive permeability data to couple conformational ensembles to experiment. We anticipate that this dataset will enable the development of machine learning models that can improve peptide design and optimization for novel therapeutics.


Asunto(s)
Aprendizaje Automático , Péptidos/química , Conformación Proteica , Compuestos Macrocíclicos/química , Péptidos Cíclicos/química
9.
Anal Chem ; 96(36): 14490-14498, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39185815

RESUMEN

Bacterial infections have emerged as a significant contributor to global mortality and morbidity rates. Herein, we introduce a dual fluorescence "turn-on" supramolecular sensor array composed of three assembled complexes (C1-C3), formed from three positively charged fluorophores (A1-A3) and one cucurbit[7]uril (CB[7]). The ability of this three-element array to simultaneously recognize 10 bacterial species within just 30 s was remarkable, boasting an impressive 100% accuracy. Additionally, the array excelled at distinguishing among various bacterial mixtures and enabled the quantitative detection of common bacterial strains. Notably, it has been skillfully applied to differentiate 10 bacterial samples in urine, achieving excellent differentiation and showcasing promising potential for medical diagnostic applications.


Asunto(s)
Hidrocarburos Aromáticos con Puentes , Colorantes Fluorescentes , Imidazoles , Imidazoles/química , Hidrocarburos Aromáticos con Puentes/química , Colorantes Fluorescentes/química , Bacterias/aislamiento & purificación , Humanos , Espectrometría de Fluorescencia , Compuestos Heterocíclicos con 2 Anillos , Compuestos Macrocíclicos , Imidazolidinas
10.
Eur J Med Chem ; 277: 116733, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-39098132

RESUMEN

Macrocyclic compounds have emerged as potent tools in the field of drug design, offering unique advantages for enhancing molecular recognition, improving pharmacokinetic properties, and expanding the chemical space accessible to medicinal chemists. This review delves into the evolutionary trajectory of macrocyclic-based strategies, tracing their journey from laboratory innovations to clinical applications. Beginning with an exploration of the defining structural features of macrocycles and their impact on drug-like characteristics, this discussion progresses to highlight key design principles that have facilitated the development of diverse macrocyclic drug candidates. Through a series of illustrative representative case studies from approved macrocyclic drugs and candidates spanning various therapeutic areas, particular emphasis is placed on their efficacy in targeting challenging protein-protein interactions, enzymes, and receptors. Additionally, this review thoroughly examines how macrocycles effectively address critical issues such as metabolic stability, oral bioavailability and selectivity. Valuable insights into optimization strategies employed during both approved and clinical phases underscore successful translation of promising leads into efficacious therapies while providing valuable perspectives on harnessing the full potential of macrocycles in drug discovery and development endeavors.


Asunto(s)
Diseño de Fármacos , Compuestos Macrocíclicos , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/farmacología , Compuestos Macrocíclicos/síntesis química , Humanos , Estructura Molecular , Animales
11.
J Am Chem Soc ; 146(36): 25383-25393, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39196894

RESUMEN

The regulation of the cell membrane potential plays a crucial role in governing the transmembrane transport of various ions and cellular life processes. However, in situ and on-demand modulation of cell membrane potential for ion channel regulation is challenging. Herein, we have constructed a supramolecular assembly system based on water-soluble cationic oligo(phenylenevinylene) (OPV) and cucurbit[7]uril (CB[7]). The controllable disassembly of OPV/4CB[7] combined with the subsequent click reaction provides a step-by-step adjustable surface positive potential. These processes can be employed in situ on the plasma membrane to modulate the membrane potential on-demand for precisely controlling the activation of the transient receptor potential vanilloid 1 (TRPV1) ion channel and up-regulating exogenous calcium-responsive gene expression. Compared with typical optogenetics, electrogenetics, and mechanogenetics, our strategy provides a perspective supramolecular genetics toolbox for the regulation of membrane potential and downstream intracellular gene regulation events.


Asunto(s)
Imidazoles , Potenciales de la Membrana , Imidazoles/química , Humanos , Hidrocarburos Aromáticos con Puentes/química , Polivinilos/química , Membrana Celular/metabolismo , Membrana Celular/química , Canales Catiónicos TRPV/metabolismo , Células HEK293 , Calcio/metabolismo , Calcio/química , Canales de Calcio/metabolismo , Canales de Calcio/química , Compuestos Heterocíclicos con 2 Anillos , Compuestos Macrocíclicos , Imidazolidinas
12.
J Med Chem ; 67(17): 14768-14785, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39171975

RESUMEN

Macrocycles are one of nature's preferred choices to generate large but cell-permeable bioactive molecules. Macrocyclization is increasingly prominent in medicinal chemistry beyond natural products, especially for difficult-to-drug targets. However, strategies to best exploit the potential of macrocycles are only beginning to emerge. Here we survey drug discovery campaigns from the past decade that cumulated in advanced macrocyclic drug-like compounds or drug candidates. Most macrocycles were conceived by ring closing based on U- or C-shaped bioactive conformations observed in co-crystal structures. We focus on the key step from linear precursors to the first macrocycle and the follow-up optimization of the resulting macrocyclic scaffold. Conformational control recurrently emerged as a key factor for macrocycle properties and linkers as an opportunity for optimization. With increasingly challenging drug targets, we expect these trends to become more prominent and relevant.


Asunto(s)
Descubrimiento de Drogas , Compuestos Macrocíclicos , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/farmacología , Compuestos Macrocíclicos/síntesis química , Ciclización , Humanos , Conformación Molecular
13.
J Am Chem Soc ; 146(35): 24348-24357, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39182188

RESUMEN

Interactions between proteins and α-helical peptides have been the focus of drug discovery campaigns. However, the large interfaces formed between multiple turns of an α-helix and a binding protein represent a significant challenge to inhibitor discovery. Modified peptides featuring helix-stabilizing macrocycles have shown promise as inhibitors of these interactions. Here, we tested the ability of N-terminal to side-chain thioether-cyclized peptides to inhibit the α-helix binding protein Mcl-1, by screening a trillion-scale library. The enriched peptides were lariats featuring a small, four-amino-acid N-terminal macrocycle followed by a short linear sequence that resembled the natural α-helical Mcl-1 ligands. These "Heliats" (helical lariats) bound Mcl-1 with tens of nM affinity, and inhibited the interaction between Mcl-1 and a natural peptide ligand. Macrocyclization was found to stabilize α-helical structures and significantly contribute to affinity and potency. Yet, the 2nd and 3rd positions within the macrocycle were permissible to sequence variation, so that a minimal macrocyclic motif, of an N-acetylated d-phenylalanine at the 1st position thioether connected to a cysteine at the 4th, could be grafted into a range of peptides and stabilize helical conformations. We found that d-stereochemistry is more helix-stabilizing than l- at the 1st position in the motif, as the d-amino acid can utilize polyproline II torsional angles that allow for more optimal intrachain hydrogen bonding. This mixed stereochemistry macrocyclic N-cap is synthetically accessible, requiring only minor modifications to standard solid-phase peptide synthesis, and its compatibility with peptide screening can provide ready access to helix-focused peptide libraries for de novo inhibitor discovery.


Asunto(s)
Compuestos Macrocíclicos , Proteína 1 de la Secuencia de Leucemia de Células Mieloides , Péptidos , Estereoisomerismo , Péptidos/química , Péptidos/síntesis química , Péptidos/farmacología , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/antagonistas & inhibidores , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/química , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/farmacología , Humanos , Conformación Proteica en Hélice alfa , Modelos Moleculares
14.
Molecules ; 29(16)2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39202907

RESUMEN

Efficient delivery of therapeutic agents to the lesion site or specific cells is an important way to achieve "toxicity reduction and efficacy enhancement". Macrocycles have always provided many novel ideas for drug or gene loading and delivery processes. Specifically, macrocycles represented by crown ethers, cyclodextrins, cucurbit[n]urils, calix[n]arenes, and pillar[n]arenes have unique properties, which are different cavity structures, good biocompatibility, and good stability. Benefited from these diverse properties, a variety of supramolecular drug delivery systems can be designed and constructed to effectively improve the physical and chemical properties of guest molecules as needed. This review provides an outlook on the current application status and main limitations of macrocycles in supramolecular drug delivery systems.


Asunto(s)
Sistemas de Liberación de Medicamentos , Compuestos Macrocíclicos , Compuestos Macrocíclicos/química , Humanos , Portadores de Fármacos/química , Ciclodextrinas/química , Calixarenos/química , Sustancias Macromoleculares/química , Éteres Corona/química
15.
Dalton Trans ; 53(35): 14634-14647, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39163366

RESUMEN

Indium-111 (111In) is a diagnostic radiometal that is important in nuclear medicine for single-photon emission computed tomography (SPECT). In order to apply this radiometal, it needs to be stably chelated and conjugated to a targeting vector that delivers it to diseased tissue. Identifying effective chelators that are capable of binding and retaining [111In]In3+in vivo is an important research area. In this study, two 18-membered macrocyclic chelators, py-macrodipa and py2-macrodipa, were investigated for their ability to form stable coordination complexes with In3+ and to be effectively radiolabeled with [111In]In3+. The In3+ complexes of these two chelators were characterized by NMR spectroscopy, X-ray crystallography, and density functional theory calculations. These studies show that both py-macrodipa and py2-macrodipa form 8-coordinate In3+ complexes and attain an asymmetric conformation, consistent with prior studies on this ligand class with small rare earth metal ions. Spectrophotometric titrations were carried out to determine the thermodynamic stability constants (log KML) of [In(py-macrodipa)]+ and [In(py2-macrodipa)]+, which were found to be 18.96(6) and 19.53(5), respectively, where the values in parentheses are the errors of the last significant figures obtained from the standard deviation from three independent replicates. Radiolabeling studies showed that py-macrodipa and py2-macrodipa can quantitatively be radiolabeled with [111In]In3+ at 25 °C within 5 min, even at ligand concentrations as low as 1 µM. The in vitro stability of the radiolabeled complexes was investigated in human serum at 37 °C, revealing that ∼90% of [111In][In(py-macrodipa)]+ and [111In][In(py2-macrodipa)]+ remained intact after 7 days. The biodistribution of these radiolabeled complexes in mice was investigated, showing lower uptake in the kidneys, liver, and blood at the 24 h mark compared to [111In]InCl3. These results demonstrate the potential of py-macrodipa and py2-macrodipa as chelators for [111In]In3+, suggesting their value for SPECT radiopharmaceuticals.


Asunto(s)
Quelantes , Radioisótopos de Indio , Compuestos Macrocíclicos , Quelantes/química , Compuestos Macrocíclicos/química , Animales , Radioisótopos de Indio/química , Ratones , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Teoría Funcional de la Densidad , Distribución Tisular , Modelos Moleculares , Radiofármacos/química , Indio/química , Cristalografía por Rayos X , Estructura Molecular
16.
J Med Chem ; 67(15): 12534-12552, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39028937

RESUMEN

Macrocyclization of acyclic compounds is a powerful strategy for improving inhibitor potency and selectivity. Here we have optimized 2-aminopyrimidine-based macrocycles to use these compounds as chemical tools for the ephrin kinase family. Starting with a promiscuous macrocyclic inhibitor, 6, we performed a structure-guided activity relationship and selectivity study using a panel of over 100 kinases. The crystal structure of EPHA2 in complex with the developed macrocycle 23 provided a basis for further optimization by specifically targeting the back pocket, resulting in compound 55, a potent inhibitor of EPHA2/A4 and GAK. Subsequent front-pocket derivatization resulted in an interesting in cellulo selectivity profile, favoring EPHA4 over the other ephrin receptor kinase family members. The dual EPHA2/A4 and GAK inhibitor 55 prevented dengue virus infection of Huh7 liver cells. However, further investigations are needed to determine whether this was a compound-specific effect or target-related.


Asunto(s)
Inhibidores de Proteínas Quinasas , Pirimidinas , Receptor EphA2 , Humanos , Línea Celular Tumoral , Cristalografía por Rayos X , Virus del Dengue/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/farmacología , Compuestos Macrocíclicos/síntesis química , Modelos Moleculares , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/síntesis química , Proteínas Serina-Treonina Quinasas , Pirimidinas/química , Pirimidinas/farmacología , Pirimidinas/síntesis química , Receptor EphA2/antagonistas & inhibidores , Receptor EphA2/metabolismo , Relación Estructura-Actividad , Morfolinas
17.
Bioorg Chem ; 151: 107625, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39013241

RESUMEN

Ten macrocyclic peptides, each comprising 14 amino acids, were designed and synthesized based on the Tau aggregation model hexapeptides AcPHF6* and AcPHF6. The design took into account the aggregation tendencies of each residue in AcPHF6* and AcPHF6, their aggregation models, while employing peptide-based structural design principles including N-methylation to promote turns and to block hydrogen bond propagation and elongation of the aggregation chain. NMR analysis supported that all these peptides adopted an antiparallel ß-sheet conformation. Self-aggregation studies characterized the aggregation properties of these peptides, identifying two peptides with the highest (P3) and lowest (P8) aggregation tendencies. In cross-aggregation studies with the parent peptides AcPHF6* and AcPHF6, P3 and P8 were found to promote and reduce aggregation, respectively. Furthermore, P3 and P8 demonstrated an enhancement and diminution effect on the aggregation of K18wt, indicating their capacity to modulate aggregation even at the macromolecular level. Thus, the two simple peptides, P3 and P8 selectively exhibit pro- or anti-aggregation effects on PHF peptides and Tau. This study, has thus developed structurally well-defined non-complex peptides, derived from AcPHF6* and AcPHF6, to modulate Tau aggregation as desired, offering applications in Tau model studies and the development of Tau aggregation inhibitors or promoters.


Asunto(s)
Agregado de Proteínas , Proteínas tau , Proteínas tau/metabolismo , Proteínas tau/química , Proteínas tau/antagonistas & inhibidores , Agregado de Proteínas/efectos de los fármacos , Humanos , Estructura Molecular , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacología , Péptidos Cíclicos/síntesis química , Oligopéptidos/química , Oligopéptidos/farmacología , Oligopéptidos/síntesis química , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/farmacología , Compuestos Macrocíclicos/síntesis química , Relación Dosis-Respuesta a Droga
18.
J Am Chem Soc ; 146(30): 20868-20877, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39024122

RESUMEN

Contemporary developments in the field of peptide macrocyclization methodology are imperative for enabling the advance of drug design in medicinal chemistry. This report discloses a Rh(III)-catalyzed macrocyclization via carboamidation, reacting acryloyl-peptide-dioxazolone precursors and arylboronic acids to form complex cyclic peptides with concomitant incorporation of noncanonical α-amino acids. The diverse and modular technology allows for expedient access to a wide variety of cyclic peptides from 4 to 15 amino acids in size and features simultaneous formation of unnatural phenylalanine and tyrosine derivatives with up to >20:1 diastereoselectivity. The reaction showcases an expansive substrate scope with 45 examples and is compatible with the majority of standard protected amino acids used in Fmoc-solid phase peptide synthesis. The methodology is applied to the synthesis of multiple peptidomimetic macrocyclic analogs, including derivatives of cyclosomatostatin and gramicidin S.


Asunto(s)
Péptidos Cíclicos , Rodio , Rodio/química , Catálisis , Péptidos Cíclicos/química , Péptidos Cíclicos/síntesis química , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/síntesis química , Ciclización , Estructura Molecular
19.
Inorg Chem ; 63(30): 14241-14255, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39024562

RESUMEN

The interest in mercury radioisotopes, 197mHg (t1/2 = 23.8 h) and 197gHg (t1/2 = 64.14 h), has recently been reignited by the dual diagnostic and therapeutic nature of their nuclear decays. These isotopes emit γ-rays suitable for single photon emission computed tomography imaging and Auger electrons which can be exploited for treating small and metastatic tumors. However, the clinical utilization of 197m/gHg radionuclides is obstructed by the lack of chelators capable of securely binding them to tumor-seeking vectors. This work aims to address this challenge by investigating a series of chemically tailored macrocyclic platforms with sulfur-containing side arms, namely, 1,4,7,10-tetrakis[2-(methylsulfanyl)ethyl]-1,4,7,10-tetraazacyclododecane (DO4S), 1,4,7-tris[2-(methylsulfanyl)ethyl]-1,4,7,10-tetraazacyclododecane (DO3S), and 1,7-bis[2-(methylsulfanyl)ethyl]-1,4,7,10-tetraazacyclododecane-4,10-diacetic acid (DO2A2S). 1,4,7,10-Tetrazacyclododecane-1,4,7,10-tetracetic acid (DOTA), the widest explored chelator in nuclear medicine, and the nonfunctionalized backbone 1,4,7,10-tetrazacyclododecane (cyclen) were considered as well to shed light on the role of the sulfanyl arms in the metal coordination. To this purpose, a comprehensive experimental and theoretical study encompassing aqueous coordination chemistry investigations through potentiometry, nuclear magnetic resonance (NMR) spectroscopy, X-ray crystallography, and density functional theory (DFT) calculations, as well as concentration- and temperature-dependent [197m/gHg]Hg2+ radiolabeling and in vitro stability assays in human serum was conducted. The obtained results reveal that the investigated chelators rapidly complex Hg2+ in aqueous media, forming extremely thermodynamically stable 1:1 metal-to-ligand complexes with superior stabilities compared to those of DOTA or cyclen. These complexes exhibited 6- to 8-fold coordination environments, with donors statically bound to the metal center, as evidenced by the presence of 1H-199Hg spin-spin coupling via NMR. A similar octacoordinated environment was also found for DOTA in both solution and solid state, but in this case, multiple slowly exchanging conformers were detected at ambient temperature. The sulfur-rich ligands quantitatively incorporate cyclotron-produced [197m/gHg]Hg2+ under relatively mild reaction conditions (pH = 7 and T = 50 °C), with the resulting radioactive complexes exhibiting decent stability in human serum (up to 75% after 24 h). By developing viable chelators and understanding the impact of structural modifications, our research addresses the scarcity of suitable chelating agents for 197m/gHg, offering promise for its future in vivo application as a theranostic Auger-emitter radiometal.


Asunto(s)
Ciclamas , Compuestos Macrocíclicos , Humanos , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/síntesis química , Mercurio/química , Azufre/química , Radioisótopos/química , Estructura Molecular , Electrones , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Compuestos Heterocíclicos/química , Nanomedicina Teranóstica
20.
Int J Mol Sci ; 25(12)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38928512

RESUMEN

Hexaazamacrocyclic Schiff bases have been extensively combined with lanthanoid (Ln) ions to obtain complexes with a highly axial geometry. However, the use of flexible hexaazatetraamine macrocycles containing two pyridines and acyclic spacers is rather uncommon. Accordingly, we obtained [DyL(OAc)2]OAc·7H2O·EtOH and [DyLMe2(Cl)2]Cl·2H2O, where L and LMe2 are the 18-membered macrocycles 3,6,10,13-tetraaza-1,8(2,6)-dipyridinacyclotetradecaphane and 3,10-dimethyl-3,6,10,13-tetraaza-1,8(2,6)-dipyridinacyclotetradecaphane, respectively, which contain ethylene and methylethylene spacers between their N3 moieties. [DyL(OAc)2]OAc·7H2O·EtOH represents the first crystallographically characterized lanthanoid complex of L, while [DyLMe2(Cl)2]Cl·2H2O contributes to increasing the scarce number of LnIII compounds containing LMe2. Furthermore, the crystal structure of L·12H2O was solved, and it was compared with those of other related macrocycles previously published. Likewise, the crystal structures of the DyIII complexes were compared with those of the lanthanoid and d-metal complexes of other 18-membered N6 donor macrocycles. This comparison showed some effect of the spacers employed, as well as the influence of the size of the ancillary ligands and the metal ion. Additionally, the distinct folding behaviors of these macrocycles influenced their coordination geometries. Moreover, the luminescent properties of [DyL(OAc)2]OAc·7H2O·EtOH and [DyLMe2(Cl)2]Cl·2H2O were also investigated, showing that both complexes are fluorescent, with the emission being sensitized by the ligands.


Asunto(s)
Complejos de Coordinación , Compuestos Macrocíclicos , Compuestos Macrocíclicos/química , Ligandos , Complejos de Coordinación/química , Elementos de la Serie de los Lantanoides/química , Cristalografía por Rayos X , Modelos Moleculares , Estructura Molecular
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