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21.
Olive oil (OO) and its phenolic compounds are reported to possess many potential biological effects, which are ascribed to its powerful antioxidant property. In this study, we have assessed whether OO and its phenolic compound tyrosol (TY) could mitigate 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced oxidative damages in peripheral blood mononuclear cells (PBMC). The results showed that exposure of PBMC to 10 nM TCDD caused significant cell death and elevated cellular concentrations of reactive oxygen species and lipid peroxidation. Comet assay indicated that OO and TY protected DNA damage against dioxin toxicity. In addition, alterations in levels of antioxidant enzymes were substantially prevented by OO and TY. TCDD-induced CYP1A1 activity and loss of mitochondrial membrane potential were significantly reduced by the administration of OO and TY. The results suggested that dietary modifications incorporating diets rich in OO and associated phenolics could prove beneficial in protecting individuals against toxicity induced by dioxins. 相似文献
22.
《Angewandte Chemie (International ed. in English)》2017,56(10):2720-2724
N‐Heterocyclic carbene based pincer ligands bearing a central silyl donor, [CSiC]−, have been envisioned as a class of strongly σ‐donating ligands that can be used for synthesizing electron‐rich transition‐metal complexes for the activation of inert bonds. However, this type of pincer ligand and complexes thereof have remained elusive owing to their challenging synthesis. We herein describe the first synthesis of a CSiC pincer ligand scaffold through the coupling of a silyl–NHC chelate with a benzyl–NHC chelate induced by one‐electron oxidation in the coordination sphere of a cobalt complex. The monoanionic CSiC ligand stabilizes the CoI dinitrogen complex [(CSiC)Co(N2)] with an unusual coordination geometry and enables the challenging oxidative addition of E−H bonds (E=C, N, O) to CoI to form CoIII complexes. The structure and reactivity of the cobalt(I) complex are ascribed to the unique electronic properties of the CSiC pincer ligand, which provides a strong trans effect and pronounced σ‐donation. 相似文献
23.
Dr. Rajesh Seenivasan Charles Kolodziej Prof. Chandran Karunakaran Prof. Clemens Burda 《Chemical record (New York, N.Y.)》2017,17(9):886-901
Over the past several decades, nanotechnology has contributed to the progress of biomedicine, biomarker discovery, and the development of highly sensitive electroanalytical / electrochemical biosensors for in vitro and in vivo monitoring, and quantification of oxidative and nitrosative stress markers like reactive oxygen species (ROS) and reactive nitrogen species (RNS). A major source of ROS and RNS is oxidative stress in cells, which can cause many human diseases, including cancer. Therefore, the detection of local concentrations of ROS (e. g. superoxide anion radical; O2•−) and RNS (e. g. nitric oxide radical; NO• and its metabolites) released from biological systems is increasingly important and needs a sophisticated detection strategy to monitor ROS and RNS in vitro and in vivo. In this review, we discuss the nanomaterials‐based ROS and RNS biosensors utilizing electrochemical techniques with emphasis on their biomedical applications. 相似文献
24.
Formation of active phases of Fe/C,Cr/C and Fe–Cr/C catalysts in oxidative dehydrogenation of ethane
《Mendeleev Communications》2023,33(3):422-424
The oxidative dehydrogenation of ethane into ethylene using CO2 as an oxidant at temperatures of 650–750 °C was carried out over Fe/C, Cr/C and Fe–Cr/C catalysts deposited on a carbon support. Before and after the reaction the catalysts were investigated by X-ray powder diffraction (XRD), in situ magnetometry and transmission electron microscopy methods. The correlation between activity of Fe/C, Cr/C and Fe–Cr/C catalytic systems and their phase composition was established. 相似文献
25.
Dinesh Singla Prof. Vijay Luxami Prof. Kamaldeep Paul 《European journal of organic chemistry》2023,26(34):e202300531
Palladium-catalyzed [4+2] oxidative annulation of coumarin-benzimidazoles with olefins for the synthesis of polycyclic aromatic hydrocarbons have been achieved. This synthetic protocol gives access to a wide range of structurally distinct imidazo[1,2-a]chromeno[3,4-c]pyridines in moderate to good yield with wide functional group tolerance. Further, photophysical properties of annulated scaffolds have been examined, which discloses their interesting solvatochromic emission behaviors. 相似文献
26.
Hongwu Jiang Kaiwen Li Shuangfeng Dong Prof. Zhuqi Chen Prof. Guochuan Yin 《European journal of organic chemistry》2023,26(35):e202300598
Transition-metal-catalyzed oxidative C−H amination reactions are among the most attractive topics in organic synthesis to construct nitrogen-containing motifs. The challenge is that most of these reactions employed stoichiometric oxidants to achieve satisfied catalytic efficiencies. Herein, we report a Pd(II)/LA-catalyzed (LA: Lewis acid) oxidative C−H amination reaction of 2-acetaminobiphenyls to construct carbazoles by using dioxygen balloon as the sole oxidant source, and the presence of LA sharply improved the catalytic efficiency of Pd(OAc)2. Remarkably, in certain cases, the deacetylation of the annulation product happened under standard conditions to afford free carbazoles as the final product. The H/D exchange studies confirmed the reversibility of C−H activation and also disclosed multiple C−H activation sites by using −NAc and −NTs as the directing groups. In addition, the palladacycle compound was identified through 1H NMR characterizations and proved to be the intermediate prior to the carbazole formation. 相似文献
27.
Dr. Shuai Zhao Bin-Wei Lu Ning Bao Zi-Jian Yin Dr. Mingcheng Qian Lin Cao Min Geng Ye Lin Prof. Dr. Xin Chen 《European journal of organic chemistry》2023,26(2):e202201239
A palladium-catalyzed oxidative amidation of conjugated olefin with 2-pyridone is described. A series of E-Enamides were synthesized in a highly stereocontrolled manner. The reaction also accommodates other cyclic and acyclic amides. Z-Enamides were predominantly prepared for primary amides probably due to the presence of an intramolecular hydrogen bond. Gram-scale synthesis of enamide and the following oxidative annulation with diphenylacetylene demonstrates the synthetic utility of this reaction. 相似文献
28.
Mona M. Amer Ahmed A. Habib Sherin F. Hammad Amira H. Kamal 《Journal of separation science》2023,46(14):2300135
A green micellar stability-indicating high-performance liquid chromatography method was developed for rupatadine fumarate determination in existence with its main impurity desloratadine. Separation was attained using Hypersil ODS column (150 × 4.6 mm, 5 μm), the micellar mobile phase consisted of 0.13 M sodium dodecyl sulfate, 0.1 M disodium hydrogen phosphate adjusted by phosphoric acid to pH 2.8 and 10% n-butanol. The column was maintained at 45◦C and detection was carried out at 267 nm. A linear response was achieved over the range of 2–160 μg/ml for rupatadine and 0.4–8 μg/ml for desloratadine. The method was applied for rupatadine determination in alergoliber tablets and alergoliber syrup without the interference of methyl paraben and propyl paraben present as main excipients. Rupatadine fumarate revealed pronounced susceptibility to oxidation; further study of oxidative degradation kinetics was carried out. Rupatadine was found to follow pseudo-first-order kinetics when exposed to 10% H2O2 at 60 and 80°C and the activation energy was found to be 15.69 Kcal/mol. At a lower temperature (40°C), degradation kinetics regression was best fitted as a polynomial quadratic relationship, thus rupatadine oxidation at a lower temperature tends to adopt a second-order kinetics rate. Oxidative degradation product structure was revealed using infrared and found to be rupatadine N-oxide at all temperature values. 相似文献
29.
《印度化学会志》2023,100(3):100906
In this work, we report an electrochemical cholesterol biosensor based on cholesterol oxidase(ChOx) enzyme immobilized on TiO2- nanoparticles – reduced graphene oxide(rGO) – polypyrrole (PPy) nanocomposite modified electrode.The electrochemical properties of GCE modified PPy (PPy-GCE) were studied using CV (Cyclic Voltammetry) and DPV (Differential Pulse Voltammetry). The developed sensor exhibited piecewise linearity from 0.1 μM to 1 μM and from 1 μM to 600 μM with the sensitivity of 61.665 and 0.1466 (2 mA mM × cm) respectively. The limit of detection of the sensor was found to be 32 nm. 相似文献
30.
Miguel Reina Eduardo Gabriel Guzmán-López Annia Galano 《International journal of quantum chemistry》2023,123(2):e27011
A set of new rasagiline derivatives is presented. They were designed to be antioxidant compounds with the potential to be used for treating neurodegenerative disorders. They are expected to be multifunctional molecules that can help reduce oxidative stress, which is thought to contribute to neurodegenerative disorders. The CADMA-Chem computational protocol was used to produce rasagiline derivatives and to evaluate their likeliness as oral drugs and antioxidants. Three of them were identified as the most promising ones. They are proposed to be better free radical scavengers than rasagiline. In addition, they are expected to keep the parent's molecule neuroprotective capability. Hopefully, the results presented here would promote further experimental and theoretical investigations on these compounds. 相似文献