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1.
Chem Biodivers ; 20(4): e202300152, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36914576

RESUMO

A new chelating task-specific ionic liquid (TSIL), lutidinium-based salicylaldoxime (LSOH), and its square pyramidal vanadyl(II) complex (VO(LSO)2 ) have been successfully synthesized and structurally characterized using elemental (CHN), spectral, and thermal analyses. The catalytic activity of the lutidinium-salicylaldoxime complex (VO(LSO)2 ) in the alkene epoxidation reactions was studied under various reaction conditions, such as solvent effect, alkene/oxidant molar ratio, pH, reaction temperature, reaction time, and the catalyst dose. The results demonstrated that the CHCl3 solvent, 1 : 3 of the cyclohexene/H2 O2 ratio, pH 8, temperature of 340 K, and catalyst dose of 0.012 mmol are assigned as the optimum conditions for achieving maximum catalytic activity for VO(LSO)2 . Moreover, the VO(LSO)2 complex has the potential for application in the effective and selective epoxidation of alkenes. Notably, under optimal VO(LSO)2 conditions, cyclic alkenes convert more efficiently to their corresponding epoxides than linear alkenes.


Assuntos
Compostos de Epóxi , Líquidos Iônicos , Alcenos , Catálise , Líquidos Iônicos/química , Oximas/química , Vanádio/química , Compostos de Epóxi/síntese química , Compostos de Epóxi/química
2.
RSC Adv ; 12(44): 28364-28375, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36320495

RESUMO

We present the effective synthesis and structural characterization of three novel imidazolium-thiohydantoin ligands (IMTHs, 5a-c) and their Mn(iii) complexes (Mn(iii)IMTHs, 6a-c) in this study. The findings of elemental analyses, spectral analyses and magnetic measurements will be used to infer the stoichiometry, coordination styles, and geometrical aspects of Mn(iii)IMTHs. The new compounds were evaluated for their chemotherapeutic potential against ESKAPE pathogens and liver cancer (HepG2). According to the MIC and MBC values, the bactericidal and bacteriostatic activities of IMTHs have been significantly improved following coordination with the Mn(iii) ion. The MTT assay results showed that all Mn(iii)IMTHs had the potential to reduce the viability of liver carcinoma (HepG2) cells in a dose-dependent manner, with the BF4-supported complex (6b) outperforming its counterparts (6a and 6c) as well as a clinical anticancer drug (VBL). Additionally, Mn-IMTH2 (6b) showed the highest level of selectivity (SI = 32.05) for targeting malignant cells (HepG2) over healthy cells (HL7702).

3.
Int J Biol Macromol ; 220: 482-492, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35987357

RESUMO

Bionanocomposites (BNC1,2) of binary (PPCH-Ag) and ternary (PPCH-TiO2-Ag) (PPCH = polyphosphonium chitosan-hydrazone) have been synthesized and immobilized on cellulosic fabrics (CFs) using an environmentally friendly single-step in situ methodology. The results of FTIR, TGA, EDX, SEM, and TEM investigations showed that PPCH and its BNCs were successfully formed on the surface layer of fabrics. Moreover, the BNC2-coated cloth exhibited a superhydrophobic behavior as revealed from the values of water contact angle (WCA) 152.1° and slide angle (SA) 8.7°. The cytotoxicity experiments on epithelial cells confirmed the safety of treated fabrics for human cells. The antimicrobial capabilities of the BNCs-treated textiles were greatly enhanced, with a small preference for BNC1-coated fabric, as compared to the native or other treated fabrics. In contrast, the BNC2-coated fabric demonstrated the highest anti-UV protection capabilities as indicated by its great capacity to reduce the UV transmission (UV-A, 2.1 %; UV-B, 1.8 %) as well as its UPF value (49.2). The durability tests revealed the high resistance of BNC2-CF against harsh washing conditions and their acquired functions sustainability up to 20 washing cycles.


Assuntos
Quitosana , Quitosana/química , Humanos , Hidrazonas , Têxteis , Titânio , Raios Ultravioleta , Água
4.
Int J Biol Macromol ; 152: 709-717, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32119949

RESUMO

One of the most important self-defense strategies employed by bacteria to resist the action of antibiotics is a biofilm formation upon the infected surface. Thus, there is an urgent need to explore novel candidates that have potent antibacterial and anti-biofilm effects to tackle this challenge. In this endeavor, we have transformed shrimp shell wastes to N-methylated water-soluble chitosan thiomer (MWSCT) which was used as either a chelating agent or bio-reductant and capping agent for Ag(I) ions in the preparation of a Ag(I)MWSCT complex or silver nanocomposite (Ag(0)MWSCT), for targeting antibacterial and anti-biofilm applications. The antibacterial and anti-biofilm performance of the new methylated chitosan thiomer (MWSCT) and its silver architectures (Ag(I)MWSCT, Ag(0)MWSCT) were assessed in vitro against E. coli and S. aureus. These new materials have significant capacities to synergistically inhibit the proliferation of the targeted bacterial cells and biofilm formation, in a structure- and species-dependent manner. Ag(0)MWSCT emerged as the most potent compound in inhibiting the growth of bacterial strains (MICE. coli/ MICS. aureus = 0.05/ 0.34 µg/mL, 1.6-/ 2.5-times lower than that recorded for the clinical drug (ciprofloxacin, Cipro). Also, this nanocomposite showed the highest anti-biofilm effects (only 1.7% E. coli biofilm growth; 11.8% staphylococcal biofilm growth).


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Quitosana/química , Prata/química , Água/química , Escherichia coli/efeitos dos fármacos , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana/métodos , Nanocompostos/química
5.
Int J Biol Macromol ; 165(Pt B): 2750-2764, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33736280

RESUMO

A novel anticancer and anti-inflammatory agent based on hybrid curcuminoid-Gboxin analog (FLLL49-GbA) and its macromolecular silver(I) complex (Ag(I)FLLL49-GbA) have successfully synthesized. In addition, chitosan nanoparticles (CNPs) were used to encapsulate this macromolecular complex, targeting enhancing its therapeutic effect and minimizing its side impacts. The encapsulated Ag(I) complex was significantly triggered apoptosis (P < 0.05) with much more rapidly release of Ag(I)FLLL49-GbA from the CNPs at pH 5.3 than at pH 7.4, which is beneficial for cancer-targeted drug delivery. Free complex showed promising ability in preventing glucose uptake and lactate production coupled with cellular ATP depletion in cancer cells. Additionally, there was significant decrease in the inflammatory cytokines in breast cancer (MCF-7) and lung cancer (A549) cells with values of P < 0.01 and P < 0.001 after 24 h incubation. Furthermore, the death-inducing proteins have been significantly up-regulated (P < 0.01 to P < 0.001) after 36 h incubation of cancer cells. Consequently, the novel curcuminoid macromolecule showed significant feasibility in triggering the high expression of apoptotic caspases caspase 3, caspase 8, P53, and Bax (P < 0.01 to P < 0.001) after 48 h of chemotherapy. Noteworthy, the cytotoxicity of Ag(I)FLLL49-GbA was significantly increased toward cancer cells (MCF-7 > A549), while, reduced toward normal cells (HeLa) after loading on chitosan Nano-vehicles.


Assuntos
Antineoplásicos/farmacologia , Quitosana/química , Diarileptanoides/farmacologia , Neoplasias/metabolismo , Prata/farmacologia , Células A549 , Antineoplásicos/química , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Diarileptanoides/química , Sistemas de Liberação de Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Células MCF-7 , Nanopartículas , Neoplasias/tratamento farmacológico , Prata/química , Regulação para Cima
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 134: 288-301, 2015 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25022501

RESUMO

Given the great importance of the various uses of 1,8-naphthalimides in the trends of biology, medicine and industry, the current study focused on extending the scope of these dyes by introducing some of their charge-transfer (CT) complexes. For this purpose, two highly fluorescent bis-1,8-naphthalimide dyes and their complexes with some π-acceptors have been synthesized and characterized spectroscopically. The π-acceptors include picric acid (PA), chloranilic acid (CLA), tetracyanoquinodimethane (TCNQ) and dichlorodicyanobenzoquinone (DDQ). The molecular structure, spectroscopic and fluorescence properties as well as the binding modes were deduced from IR, UV-vis and (1)H NMR spectral studies. The binding ratio of complexation was determined to be 1:1 according to the elemental analyses and photometric titrations. It has been found that the order of acceptance ability for the different acceptors is TCNQ>DDQ>CLA>PA. The photostability of 1,8-naphthalimide dye as a donor and its charge-transfer complex doped in polymethyl methacrylate/PMMA were exposed to UV-Vis radiation and the change in the absorption spectra was achieved at different times during irradiation period.


Assuntos
Corantes Fluorescentes/química , Benzoquinonas/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Nitrilas/química , Fotoquímica/métodos , Picratos/química , Polimetil Metacrilato/química , Soluções , Espectrofotometria Infravermelho , Raios Ultravioleta
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