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1.
Adv Mater ; 36(21): e2312137, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38350009

RESUMEN

Manipulation of directional magnon propagation, known as magnon spin current, is essential for developing magnonic devices featuring nonvolatile functionalities and ultralow power consumption. Magnon spin current can usually be modulated by magnetic field or current-induced spin torques. However, these approaches may lead to energy dissipation due to Joule heating. Electric-field switching of magnon spin current without charge current is highly preferred but challenging to realize. By integrating magnonic and piezoelectric materials, the manipulation of the magnon spin current generated by the spin Seebeck effect in the ferrimagnetic insulator Gd3Fe5O12 (GdIG) film on a piezoelectric substrate is demonstrated. Reversible electric-field switching of magnon polarization without applied charge current is observed. Through strain-mediated magnetoelectric coupling, the electric field induces the magnetic compensation transition between two magnetic states of the GdIG, resulting in its magnetization reversal and the simultaneous switching of magnon spin current. This work establishes a prototype material platform that paves the way for developing magnon logic devices characterized by all electric field reading and writing and reveals the underlying physics principles of their functions.

2.
Molecules ; 28(20)2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37894668

RESUMEN

The C-3 modification of 1H-indazole has produced active pharmaceuticals for the treatment of cancer and HIV. But, so far, this transformation has seemed less available, due to the lack of efficient C-C bond formation at the less reactive C-3 position. In this work, a series of silica gel-supported PdO2 nanoparticles of 25-66 nm size were prepared by ball milling silica gel with divalent palladium precursors, and then employed as catalysts for the Suzuki-Miyaura cross-coupling of 1H-indazole derivative with phenylboronic acid. All the synthesized catalysts showed much higher cross-coupling yields than their palladium precursors, and could also be reused three times without losing high activity and selectivity in a toluene/water/ethanol mixed solvent. Although the palladium precursors showed an order of activity of PdCl2(dppf, 1,1'-bis(diphenylphosphino)ferrocene) > PdCl2(dtbpf, 1,1'-bis(di-tert-butylphosphino)ferrocene) > Pd(OAc, acetate)2, the synthesized catalysts showed an order of C1 (from Pd(OAc)2) > C3 (from PdCl2(dtbpf)) > C2 (from PdCl2(dppf)), which conformed to the orders of BET (Brunauer-Emmett-Teller) surface areas and acidities of these catalysts. Notably, the most inexpensive Pd(OAc)2 can be used as a palladium precursor for the synthesis of the best catalyst through simple ball milling. This work provides a highly active and inexpensive series of catalysts for C-3 modification of 1H-indazole, which are significant for the large-scale production of 1H-indazole-based pharmaceuticals.

3.
Talanta ; 252: 123895, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36067697

RESUMEN

The separation and purification of proteins is an essential precondition for proteomics research because of the intricate matrix environment. Hence, a facile method has been developed to synthesize hyperbranched polyethyleneimine modified magnetic nanomaterials (Fe3O4-NH2-BPEI) with dendritic structure, unique electrostatic effect, and abundant functional groups for the selective adsorption of proteins which greatly avoids the drawbacks of time consumption and leakage of metal ions in traditional pre-treatment. The preparation conditions, physical and chemical properties, and adsorption performance of Fe3O4-NH2-BPEI have been fully studied. The obtained materials have stable crystal shape, adequate superparamagnetism, fast adsorption kinetics, high adsorption amount, and admirable reusability. In addition, the as-prepared Fe3O4-NH2-BPEI exhibits good selective adsorption ability for electronegative proteins in the neutral solution, exhibiting a potential value for special adsorption for proteins with different pI.


Asunto(s)
Nanoestructuras , Contaminantes Químicos del Agua , Adsorción , Magnetismo , Polietileneimina/química , Proteínas , Fenómenos Magnéticos , Contaminantes Químicos del Agua/química
4.
Drug Chem Toxicol ; 45(2): 741-749, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32506967

RESUMEN

Benzo(a)pyrene (BaP) is a representative polycyclic aromatic hydrocarbon (PAH) compound, which has been implicated in cancer initiation and promotion. Although BaP is one of the most extensively studied pollutants, the underlying mechanisms through which BaP affects reactive oxygen species (ROS)/hypoxia-inducible factor 1α (HIF-1α)/heme oxygenase 1(HO-1) signaling during lung or breast carcinogenesis are not yet fully understood. In this study, we analyzed the effects of 0 (control), 1, 5, or 25 µM BaP exposure on A549 and MCF-7 cancer cells, by evaluating cell viability, cell cycle, and regulatory protein expression, metabolic gene expression, and ROS/HIF-1α/HO-1 signaling. Cell viability increased following exposure to 1 and 5 µM BaP in A549 cells but decreased following exposure to all concentrations of BaP in MCF-7 cells. BaP significantly increased the proportions of cells in S and G2/M phases, with concomitant reductions in the proportions of cells in G0/G1 phase, following 5 and 25 µM exposure, which was accompanied by the upregulation of the regulatory proteins cyclin A, cyclin B, cyclin-dependent kinase (CDK)1, and CDK2. The subsequent upregulation of cytochrome p450 (CYP)1A1, CYP1B1, CYP3A4, epoxide hydrolase (EH), aldo-keto reductase (AKRC1) expression, and the attenuation of multi-drug resistance protein 4 (MRP4), glutathione-S-transferase (GST)1A1, and GST1B1 were also observed in both cell lines. Moreover, the induction of ROS and the modulation of HIF-1α and HO-1 were observed after BaP exposure. Taken together, these findings suggest that BaP affects proliferation with reference to metabolic genes and ROS/HIF-1α/HO-1 signaling in A549 and MCF-7 cancer cells.


Asunto(s)
Benzo(a)pireno , Neoplasias , Benzo(a)pireno/metabolismo , Benzo(a)pireno/toxicidad , Proliferación Celular , Humanos , Células MCF-7 , Especies Reactivas de Oxígeno , Transducción de Señal
5.
Front Chem ; 8: 532, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32793546

RESUMEN

The aqueous room temperature mono-dehydration of sugar alcohols (D-sorbitol and D-mannitol) was conducted using functionalized yttrium oxide nanocatalysts prepared via sol-gel methods. Materials exhibited high selectivity to mono-dehydration products. Solvent and catalyst effects were also investigated and discussed. The introduction of titanium into the yttrium oxide framework would decrease both substrate conversion and mono-dehydration efficiency. In addition, studies of the catalytic mechanism indicate high mono-dehydration efficiency may come from the stability of the formed intermediate during catalysis. This work provides a highly efficient and benign system for catalytic mono-dehydration of sugar alcohols.

6.
Eur J Med Chem ; 186: 111888, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31787359

RESUMEN

Targeting L858R/T790M/C797S mutant EGFR is a major challenge in the new-generation EGFR tyrosine kinase inhibitors development for conquering drug resistant NSCLC. In this study, a series of novel 9-heterocyclyl substituted 9H-purine derivatives were designed as EGFRL858 R/T790 M/C797S tyrosine kinase inhibitors. Among these compounds, D4, D9, D11 and D12 showed significantly potent anti-proliferation and EGFRL858 R/T790 M/C797S inhibition activity. In particular, the most potent compound D9 showed anti-proliferation against HCC827 and H1975 cell lines with the IC50 values of 0.00088 and 0.20 µM, respectively. And D9 inhibited the EGFRL858R/T790M/C797S with an IC50 value of 18 nM. Furtherly, D9 could significantly suppress the EGFR phosphorylation, induce the apoptosis, arrest cell cycle at G0/G1, and inhibit colony formation in HCC827 cell line by a concentration-dependent manner. Molecular docking indicated that the introduction of a cyclopropylsulfonamide group in D9 led to the formation of additional two hydrogen bonds with mutant Ser797 which played key roles in generating efficient EGFRL858 R/T790 M/C797S inhibitory activity. These findings strongly indicated that 9-heterocyclyl substituted 9H-purine derivatives were promising L858R/T790M/C797S mutant EGFR-TKIs. The introduction of extra hydrogen bond interaction with mutant Ser797 is efficient method for the design of the fourth-generation EGFR-TKIs.


Asunto(s)
Antineoplásicos/farmacología , Descubrimiento de Drogas , Compuestos Heterocíclicos/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Purinas/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Compuestos Heterocíclicos/síntesis química , Compuestos Heterocíclicos/química , Humanos , Estructura Molecular , Mutación , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Purinas/síntesis química , Purinas/química , Relación Estructura-Actividad
7.
Eur J Med Chem ; 122: 756-769, 2016 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-27526040

RESUMEN

A new series of 2-substituted imino-3-substituted-5- heteroarylidene-1,3-thiazolidine-4-ones as the potent bidentate PTP1B inhibitors were designed and synthesized in this paper. All of the new compounds were characterized and identified by spectra analysis. The biological screening test against PTP1B showed that some of these compounds have the positive inhibitory activity against PTP1B. The activity of the compounds with 5-substituted pyrrole on 5-postion of 1,3-thiazolidine-4-one are more potent than that of those compounds with 5-substituted pyridine group. Compound 14b, 14h and 14i showed IC50 values of 8.66 µM, 6.83 µM and 6.09 µM against PTP1B, respectively. Docking analysis of these active compounds with PTP1B showed the possible interaction modes of these biheterocyclic compounds with the active sites of PTP1B. The inhibition tests against oncogenetic CDC25B were also conducted on this set of compounds to evaluate the selectivity and possible anti-neoplastic activity. Compound 14b also showed the lowest IC50 of 1.66 µM against CDC25B among all the possible inhibitors, including 14g, 14h, 14i and 15c. Some pharmacological parameters including VolSurf, steric and electric descriptors of all the compounds were calculated to give some hints about the relative relationship with the biological activity. The result of this study might give some light on designing the possible anti-cancer drugs targeting at phosphatases. The most active compound 14i might be used as the lead compound for further structure modification of the new low molecular weight PTP1B inhibitors with the N-containing heterocyclic skeleton.


Asunto(s)
Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Tiazolidinas/síntesis química , Tiazolidinas/farmacología , Técnicas de Química Sintética , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/metabolismo , Humanos , Simulación del Acoplamiento Molecular , Conformación Proteica , Estructura Secundaria de Proteína , Proteína Tirosina Fosfatasa no Receptora Tipo 1/química , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Relación Estructura-Actividad , Tiazolidinas/química , Tiazolidinas/metabolismo , Fosfatasas cdc25/antagonistas & inhibidores
8.
ScientificWorldJournal ; 2014: 801346, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25136686

RESUMEN

We investigated oxidative stress/genotoxic effects levels, immunoglobulin levels, polycyclic aromatic hydrocarbons (PAHs) levels exposed in 126 coke oven workers and in 78 control subjects, and evaluated the association between oxidative stress/genotoxic effects levels and immunoglobulin levels. Significant differences were observed in biomarkers, including 1-hydroxypyrene levels, employment time, percentages of alcohol drinkers, MDA, 8-OHdG levels, CTL levels and CTM, MN, CA frequency, and IgG, IgA levels between the control and exposed groups. Slightly higher 1-OHP levels in smoking users were observed. For the dose-response relationship of IgG, IgA, IgM, and IgE by 1-OHP, each one percentage increase in urinary 1-OHP generates a 0.109%, 0.472%, 0.051%, and 0.067% decrease in control group and generates a 0.312%, 0.538%, 0.062%, and 0.071% decrease in exposed group, respectively. Except for age, alcohol and smoking status, IgM, and IgE, a significant correlation in urinary 1-OHP and other biomarkers in the total population was observed. Additionally, a significant negative correlation in genotoxic/oxidative damage biomarkers of MDA, 8-OH-dG, CTL levels, and immunoglobins of IgG and IgA levels, especially in coke oven workers, was found. These data suggest that oxidative stress/DNA damage induced by PAHs may play a role in toxic responses for PAHs in immunological functions.


Asunto(s)
Bebidas , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Linfocitos/metabolismo , Exposición Profesional/efectos adversos , Estrés Oxidativo/efectos de los fármacos , Adulto , Daño del ADN/efectos de los fármacos , Humanos , Linfocitos/efectos de los fármacos , Masculino , Hidrocarburos Policíclicos Aromáticos/toxicidad , Pirenos/sangre , Pirenos/orina
9.
Eur J Pharm Sci ; 62: 334-41, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24956462

RESUMEN

A new series of 29 diarylpyrimidine analogues featuring a cyclopropylamino group between the pyrimidine scaffold and the aryl wing have been synthesized. All of the new compounds have been characterized by spectra analysis. The target molecules were evaluated for their in vitro anti-HIV activity with FDA-approved drugs as references. Some of the compounds exhibited moderate to potent activities against wild-type HIV-1. The compound 4-((4-((cyclopropylamino)(2,5-difluorophenyl)methyl)pyrimidin-2-yl)amino)benzonitrile (1e) displayed potent anti-HIV-1 activity against WT HIV-1 with an IC50 of 0.099 µM and a selectivity index of 2302. The preliminary structure-activity relationship (SAR) of this new series of compounds was also investigated.


Asunto(s)
Fármacos Anti-VIH/síntesis química , Pirimidinas/síntesis química , Inhibidores de la Transcriptasa Inversa/síntesis química , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , Línea Celular Tumoral , Diseño de Fármacos , VIH-1/efectos de los fármacos , VIH-2/efectos de los fármacos , Humanos , Pirimidinas/química , Pirimidinas/farmacología , Inhibidores de la Transcriptasa Inversa/química , Inhibidores de la Transcriptasa Inversa/farmacología , Relación Estructura-Actividad
10.
Eur J Med Chem ; 82: 600-11, 2014 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-24952305

RESUMEN

This article reports the design, synthesis and antiviral evaluation of a new series of non-nucleoside reverse transcriptase inhibitors (NNRTIs). The basic skeleton of these target 18 molecules is diarylpyrimidine featuring a substituted amino group between the pyrimidine scaffold and the aryl wing. All of the new compounds have been characterized by spectra analysis. The entire target molecules were evaluated for their in vitro anti-HIV activity with controlling group of FDA approved drugs. Most of them showed good to potent activities against wild-type (WT) HIV-1 with IC50 values in the range of 0.0175-69.21 µM. 2-(4-Cyanophenylamino)-4-(2-cyanovinylphenylhydrazonomethyl)pyrimidine (1d) displayed potent anti-HIV-1 activity against WT HIV-1 with a selectivity index (SI) of 106367 and an IC50 value of 1.75 nM, which was 47 fold lower than that of AZT. Compound 1d also showed a broad-spectrum inhibitory activity, with an IC50 value of 5.33 µM and 5.05 µM against both HIV-1 double-mutated (K103N/Y181C) strain and HIV-2 strain, respectively. The preliminary structure-activity relationship (SAR) was also investigated. The binding modes with HIV-1 RT for both the wild type and mutant type have also been discussed.


Asunto(s)
Fármacos Anti-VIH/farmacología , Diseño de Fármacos , Transcriptasa Inversa del VIH/antagonistas & inhibidores , Pirimidinas/farmacología , Inhibidores de la Transcriptasa Inversa/farmacología , Fármacos Anti-VIH/síntesis química , Fármacos Anti-VIH/química , Relación Dosis-Respuesta a Droga , Transcriptasa Inversa del VIH/metabolismo , VIH-1/efectos de los fármacos , VIH-2/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Pirimidinas/síntesis química , Pirimidinas/química , Inhibidores de la Transcriptasa Inversa/síntesis química , Inhibidores de la Transcriptasa Inversa/química , Relación Estructura-Actividad
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