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1.
Mikrochim Acta ; 191(4): 221, 2024 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-38536529

RESUMO

The successful fabrication is reported of highly crystalline Co nanoparticles interconnected with zeolitic imidazolate framework (ZIF-12) -based amorphous porous carbon using the molten-salt-assisted approach utilizing NaCl. Single crystal diffractometers (XRD), and X-ray photoelectron spectroscopy (XPS) analyses confirm the codoped amorphous carbon structure. Crystallite size was calculated by Scherrer (34 nm) and Williamson-Hall models (42 nm). The magnetic properties of NPCS (N-doped porous carbon sheet) were studied using a vibrating sample magnetometer (VSM). The NPCS has a magnetic saturation (Ms) value of 1.85 emu/g. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses show that Co/Co3O4 nanoparticles are homogeneously distributed in the carbon matrix. While a low melting point eutectic salt acts as an ionic liquid solvent, ZIF-12, at high temperature, leading cobalt nanoparticles with a trace amount of Co3O4 interconnected by conductive amorphous carbon. In addition, the surface area (89.04 m2/g) and pore architectures of amorphous carbon embedded with Co nanoparticles are created using the molten salt approach. Thanks to this inexpensive and effective method, the optimal composite porous carbon structures were obtained with the strategy using NaCl salt and showed distinct electrochemical performance on electrochemical methodology revealing the analytical profile of Erdatifinib (ERD) as a sensor modifier. The linear response spanned from 0.01 to 7.38 µM, featuring a limit of detection (LOD) of 3.36 nM and a limit of quantification (LOQ) of 11.2 nM. The developed sensor was examined in terms of selectivity, repeatability, and reproducibility. The fabricated electrode was utilized for the quantification of Erdafitinib in urine samples and pharmaceutical dosage forms. This research provides a fresh outlook on the advancements in electrochemical sensor technology concerning the development and detection of anticancer drugs within the realms of medicine and pharmacology.


Assuntos
Antineoplásicos , Cobalto , Óxidos , Pirazóis , Quinoxalinas , Cloreto de Sódio , Reprodutibilidade dos Testes , Carbono/química
2.
Small ; : e2307225, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38054760

RESUMO

Ni/Mn-based oxide cathode materials have drawn great attention due to their high discharge voltage and large capacity, but structural instability at high potential causes rapid capacity decay. How to moderate the capacity loss while maintaining the advantages of high discharge voltage remains challenging. Herein, the replacement of Mn ions by Ga ions is proposed in the P2-Na2/3 Ni0.2 Mn0.8 O2 cathode for improving their cycling performances without sacrificing the high discharge voltage. With the introduction of Ga ions, the relative movement between the transition metal ions is restricted and more Na ions are retained in the lattice at high voltage, leading to an enhanced redox activity of Ni ions, validated by ex situ synchrotron X-ray absorption spectrum and X-ray photoelectron spectroscopy. Additionally, the P2-O2 phase transition is replaced by a P2-OP4 phase transition with a smaller volume change, reducing the lattice strain in the c-axis direction, as detected by operando/ex situ X-ray diffraction. Consequently, the Na2/3 Ni0.21 Mn0.74 Ga0.05 O2 electrode exhibits a high discharge voltage close to that of the undoped materials, while increasing voltage retention from 79% to 93% after 50 cycles. This work offers a new avenue for designing high-energy density Ni/Mn-based oxide cathodes for sodium-ion batteries.

3.
Small Methods ; 7(11): e2300635, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37572008

RESUMO

Sodium layered oxides feature in high capacity and diverse composition, however, are plagued by various issues including limited kinetics and interfacial instability with residual alkali. Conventional substitution/doping and heterogeneous coating are promising to tackle the problems of bulk and surface, respectively, but normally insufficient to address both. Herein, a post-substitution strategy is proposed to modify primary sodium-layered-oxide particles that can simultaneously deal with bulk and surficial issues. As a typical example, post Ti-substitution for O3-NaNi1/3 Fe1/3 Mn1/3 O2 is successfully performed by adjusting thermodynamic driving force, resulting in depth-controllable Ti infusion from surface to bulk, as proved by energy dispersive spectroscopy maps collected at the cross-section. Residual alkali species are efficiently diminished and benefited from the surface-to-bulk osmotic reaction, significantly improving Coulombic efficiency. Moreover, remarkable enhancements in reversible capacity (135 mAh g-1 at C/10), rate capability (74% retention at 5 C), and long-term cycling stability (80% retention after 300 cycles at 2 C) are achieved by manipulating gradient-like Ti distribution in a primary particle that brings with increased kinetics and strengthened interfacial stability, surpassing those given by rough heterotic coating and homogeneous Ti-substitution. Such post-substitution is expected to provide a universal strategy to modify primary layered-oxide particles for developing advanced cathode materials of SIBs.

4.
Nanomicro Lett ; 14(1): 181, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050520

RESUMO

Exploring new materials with high stability and capacity is full of challenges in sustainable energy conversion and storage systems. Metal-organic frameworks (MOFs), as a new type of porous material, show the advantages of large specific surface area, high porosity, low density, and adjustable pore size, exhibiting a broad application prospect in the field of electrocatalytic reactions, batteries, particularly in the field of supercapacitors. This comprehensive review outlines the recent progress in synthetic methods and electrochemical performances of MOF materials, as well as their applications in supercapacitors. Additionally, the superiorities of MOFs-related materials are highlighted, while major challenges or opportunities for future research on them for electrochemical supercapacitors have been discussed and displayed, along with extensive experimental experiences.

5.
Heliyon ; 8(8): e10133, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36016530

RESUMO

A series of symmetric and unsymmetrical benzimidazolium-based N-heterocyclic carbene (NHC) precursors (1a-i) and their silver complexes (2a-i) have been synthesized. The Ag(I)-NHC complexes were characterized by 1H, 13C{1H} NMR, FTIR, LC/MS-QTOF, and elemental analysis. Anticancer and cytotoxic activity of all Ag(I)-NHC complexes were tested against healthy fibroblast cell line (L929), breast cancer cell line (MCF-7), and neuroblastoma cell line (SH-SY5Y) by MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4sulfophenyl)-2H-tetrazolium] assay. The 2b, 2c, 2e, 2g, 2h, and 2i complexes showed higher cytotoxicity than cisplatin against SH-SY5Y and MCF-7 and lower cytotoxic activity against L929 cell lines. Because of their high cytotoxic activity against cancer cells and low cytotoxicity against healthy fibroblast cell lines, the 2b, 2c, 2e, 2g, 2h, and 2i are expected to be new lead compounds. In addition, molecular docking studies were performed to explore the binding interactions of silver complexes with the enzyme to explore new anticancer compounds. Furthermore, ADME properties of all complexes were predicted to explore lead-like characteristics and may be a potential drug candidate for cancer treatment.

6.
Turk J Chem ; 46(4): 1097-1109, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37538752

RESUMO

The 2-methylpyridine, 2-diethylaminoethyl, and isopentyl linked a series of symmetric and unsymmetric benzimidazolium salts 2a-e were prepared and used in the synthesis of silver-N-heterocyclic carbene (NHC) complexes (3a-e). The Ru(II)-NHC complexes (4a-h) were synthesized via transmetalation reaction from 3a-e. 4a-h complexes were converted to Ru(II)-NHC.HCl complexes (5ah) by HCl solution of diethyl ether and characterized by different spectroscopic techniques such as 1H and 13C NMR, LC/MS-Q-TOF, FT-IR, elemental analysis, and melting point detection. We examined the effect of the structural difference of complexes on anticancer activity via different arenes and metal centers. Antiproliferative activity of 5a-h and 3a was tested against human cervix adenocarcinoma (HeLa) and rat glioblastoma (C6) cell lines by ELISA assay. The IC50 value of 5b, 5c and 5e complexes exhibited good cytotoxic activity than cisplatin on C6 (14.2 ± 0.5 mM; 16.2 ± 0.4 mM; 24.2 ± 0.7 mM, respectively) and HeLa (11.1 ± 0.5 mM; 13.7 ± 0.3 mM; 22.8 ± 0.8 mM, respectively) cell lines.

8.
RSC Adv ; 8(70): 40000-40015, 2018 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-35558245

RESUMO

N,N-Substituted benzimidazole salts were successfully synthesized and characterized by 1H-NMR, 13C {1H} NMR and IR techniques, which support the proposed structures. Catalysts generated in situ were efficiently used for the carbonylative cross-coupling reaction of 2 bromopyridine with various boronic acids. The reaction was carried out in THF at 110 °C in the presence of K2CO3 under inert conditions and yields unsymmetrical arylpyridine ketones. All N,N-substituted benzimidazole salts 2a-i and 4a-i studied in this work were screened for their cytotoxic activities against human cancer cell lines such us MDA-MB-231, MCF-7 and T47D. The N,N-substituted benzimidazoles 2e and 2f exhibited the most cytotoxic effect with promising cytotoxic activity with IC50 values of 4.45 µg mL-1 against MDA-MB-231 and 4.85 µg mL-1 against MCF7 respectively.

9.
Molecules ; 22(3)2017 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-28272376

RESUMO

New benzimidazolium salts 1a-c and their palladium bis-N-heterocyclic carbene complexes 2a-c and palladium PEPPSI-type complexes 3a-c were designed, synthesized and structurally characterized by NMR (1H and 13C), IR, DART-TOF mass spectrometry and elemental analysis. Then these complexes 2-3 were employed in the Suzuki-Miyaura cross-coupling reaction of substituted arenes with phenylboronic acid under mild conditions in toluene and DMF/H2O (1/1) to afford functionalized biaryl derivatives in good to excellent yields. The antibacterial activity of palladium bis-N-heterocyclic carbene complexes 2a-c and palladium PEPPSI-type complexes 3a-c was measured by disc diffusion method against Gram positive and Gram negative bacteria. Compounds 2a, 2c and 3a-c exhibited potential antibacterial activity against four bacterial species among the five used indicator cells. The product 2b inhibits the growth of the all five tested microorganisms. Moreover, the antioxidant activity determination of these complexes 2-3, using 2.2-diphenyl-1-picrylhydrazyl (DPPH) as a reagent, showed that compounds 2a-c and 3b possess DPPH antiradical activity. The higher antioxidant activity was obtained from the product 2b which has radical scavenging activity comparable to that of the two used positive controls (gallic acid "GA" and tutylatedhydroxytoluene "BHT"). Investigation of the anti-acetylcholinesterase activity of the studied complexes showed that compounds 2b, 3a, and 3b exhibited moderate activity at 100 µg/mL and product 2b is the most active.


Assuntos
Ácidos Borônicos/síntese química , Ácidos Borônicos/farmacologia , Brometos/química , Cloretos/química , Paládio/química , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Catálise , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Testes de Sensibilidade Microbiana , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
10.
Molecules ; 15(2): 649-59, 2010 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-20335935

RESUMO

An efficient and stereoselective catalytic system for the Heck cross coupling reaction using novel 1,3-dialkyl-3,4,5,6-tetrahydropyrimidinium salts (1, LHX) and Pd(OAc)2 loading has been reported. The palladium complexes derived from the salts 1a-f prepared in situ exhibit good catalytic activity in the Heck coupling reaction of aryl bromides under mild conditions.


Assuntos
Brometos/química , Química Orgânica/métodos , Metano/análogos & derivados , Paládio/química , Pirimidinas/química , Sais/química , Água/química , Catálise , Ligantes , Metano/química , Pirimidinas/síntese química , Estireno/química
11.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 2): o310-1, 2009 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-21581919

RESUMO

In the title compound, C(25)H(35)N(2) (+)·Cl(-)·H(2)O, the imidazolidine ring adopts a twisted conformation, with a pseudo-twofold axis passing through the N-C-N carbon and the opposite C-C bond. The N-C-N fragment of the imidazolidine ring shows some degree of both double- and single-bond character due to partial electron delocalization. One of the tert-butyl groups is disordered over two conformations with occupancies of 0.714 (8) and 0.286 (8). In the crystal, O-H⋯Cl and C-H⋯O hydrogen bonds help to establish the packing.

12.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 3): m243-4, 2009 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-21582038

RESUMO

The title complex, [RuCl(2)(C(25)H(26)N(2))]·CH(2)Cl(2), is best thought of as containing an octa-hedrally coordinated Ru center with the arene occupying three sites. Two Ru-Cl bonds and one Ru-carbene bond complete the distorted octa-hedron. The carbene portion of the ligand is a benzimidazole ring. This ring is connected to the C(6)H(2)(CH(3))(3) arene group by a CH(2) bridge. This leads to a system with very little apparent strain. A dichloro-methane solvent mol-ecule completes the crystal structure. Further stabilization is accomplished via C-H⋯N and C-H⋯Cl interactions.

13.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 1): o121-2, 2008 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-21581583

RESUMO

In the title salt, C(26)H(29)N(2) (+)·Br(-), which may serve as a precursor for N-heterocyclic carbenes, the imidazolidine ring adopts a twist conformation with a pseudo-twofold axis passing through the N-C-N carbon and the opposite C-C bond. The N-C-N bond angle [113.0 (4)°] and C-N bond lengths [1.313 (6) and 1.305 (6) Å] confirm the existence of strong resonance in this part of the mol-ecule. In the crystal, a C-H⋯Br inter-action is present. The dihedral angle between the biphenyl rings is 64.3 (2)° and the phenyl rings make angles of 76.6 (3) and 18.5 (3)° with the plane of the imidazolidine ring.

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