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141.
Reena Agrawal Jyoti Sharma Durgesh Nandani Amala Batra Yashpal Singh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):471-480
Abstract Chloro-bis(2,2-dithio-1,3,2-dioxaphospholane/dioxaphosphorinane)bismuth(III) compounds have been synthesized by the reaction of bismuth trichloride with sodium 2,2-dithio-1,3,2-dioxaphospholane/dioxaphosphorinane in 1:2 molar ratio in benzene solution. Reactions of these chloro-bis(2,2-dithio-1,3,2-dioxaphospholane/dioxaphosphorinane)-bismuth(III) compounds with sodium tetraisopropoxyborate in equimolar ratio in benzene solution yield the corresponding heterobinuclear bismuth derivatives with boron. All compounds were characterized by elemental analyses and molecular weight measurements. Plausible structures are proposed on the basis of IR and 1H, 11B, 13C, and 31P spectroscopic studies. 2-Mercapto-2-thioxo-1,3,2-dioxaphospholanes-/dioxaphosphorinanes and the corresponding chloro-bis(2,2-dithio-1,3,2-dioxaphospholane/dioxaphosphorinane)bismuth (III) compounds show antifungal activities against Fusarium and Trichoderma. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. GRAPHICAL ABSTRACT 相似文献
142.
Palash M. Saikia Bornali Boruah Biswajit Kakoty Pankaj Hazarika 《Journal of Dispersion Science and Technology》2014,35(7):997-1002
The binding of curcumin with chitosan in the presence of nonionic surfactant, iso-octylphenoxy-polyethoxy-ethanol (Triton X-100) and its stability in such systems have been investigated by monitoring the changes in the absorption spectra at physiological pH (7.4). It was observed that curcumin binds to chitosan more than 10 times stronger in presence of TX 100 at the experimental condition. From spectrophotometric analysis of the kinetics of degradation of the dye, it was observed that the yield of suppression of degradation of curcumin by chitosan increases by 33.5% in the presence of TX 100 than alone. The interaction of the dye with chitosan has been found to be exothermic and driven by hydrophobic interactions, hydrogen bond formation, and electrostatic interactions. 相似文献
143.
Jelili A. Badmus Okobi E. Ekpo Jyoti R. Sharma Nicole Remaliah S. Sibuyi Mervin Meyer Ahmed A. Hussein Donavon C. Hiss 《Molecules (Basel, Switzerland)》2020,25(23)
Holamine and funtumine, steroidal alkaloids with strong and diverse pharmacological activities are commonly found in the Apocynaceae family of Holarrhena. The selective anti-proliferative and cell cycle arrest effects of holamine and funtumine on cancer cells have been previously reported. The present study evaluated the anti-proliferative mechanism of action of these two steroidal alkaloids on cancer cell lines (HT-29, MCF-7 and HeLa) by exploring the mitochondrial depolarization effects, reactive oxygen species (ROS) induction, apoptosis, F-actin perturbation, and inhibition of topoisomerase-I. The apoptosis-inducing effects of the compounds were studied by flow cytometry using the APOPercentageTM dye and Caspase-3/7 Glo assay kit. The two compounds showed a significantly greater cytotoxicity in cancer cells compared to non-cancer (normal) fibroblasts. The observed antiproliferative effects of the two alkaloids presumably are facilitated through the stimulation of apoptosis. The apoptotic effect was elicited through the modulation of mitochondrial function, elevated ROS production, and caspase-3/7 activation. Both compounds also induced F-actin disorganization and inhibited topoisomerase-I activity. Although holamine and funtumine appear to have translational potential for the development of novel anticancer agents, further mechanistic and molecular studies are recommended to fully understand their anticancer effects. 相似文献
144.
Monika Bhardwaj Poonam Yadav Divya Vashishth Kavita Sharma Ajay Kumar Jyoti Chahal Sunita Dalal Sudhir Kumar Kataria 《Molecules (Basel, Switzerland)》2021,26(11)
Obesity is a serious health complication in almost every corner of the world. Excessive weight gain results in the onset of several other health issues such as type II diabetes, cancer, respiratory diseases, musculoskeletal disorders (especially osteoarthritis), and cardiovascular diseases. As allopathic medications and derived pharmaceuticals are partially successful in overcoming this health complication, there is an incessant need to develop new alternative anti-obesity strategies with long term efficacy and less side effects. Plants harbor secondary metabolites such as phenolics, flavonoids, terpenoids and other specific compounds that have been shown to have effective anti-obesity properties. Nanoencapsulation of these secondary metabolites enhances the anti-obesity efficacy of these natural compounds due to their speculated property of target specificity and enhanced efficiency. These nanoencapsulated and naive secondary metabolites show anti-obesity properties mainly by inhibiting the lipid and carbohydrate metabolizing enzymes, suppression of adipogenesis and appetite, and enhancing energy metabolism. This review focuses on the plants and their secondary metabolites, along with their nanoencapsulation, that have anti-obesity effects, with their possible acting mechanisms, for better human health. 相似文献
145.
Sachini Rodrigo Disni Gunasekera Jyoti P. Mahajan Long Luo 《Current Opinion in Electrochemistry》2021
Electrochemical organic synthesis has recently attracted much attention because of its unique reactivity and environmentally benign approach. Conventional electrosynthesis uses either constant current or constant potential, known as direct current electrolysis. However, recently, alternating current electrolysis has begun receiving more attention. The purpose of this study is to give a short overview of the history and recent advances in the field of alternating current electrolysis for organic synthesis. 相似文献
146.
Pseudo‐atranes have a significant role in catalysis; however, obtaining chiral pseudo‐atranes for covalent functionalization of heterogeneous catalytic surfaces is very challenging. Herein, synthesis of a chiral tripodal amine [N{CH (CH2Ph)CH2OH}{CH2(4? Br? C6H3OH)}{CH2(2? CHO? 4? Me? C6H2OH)}] ( 1 ) and a dichiral [4.4.3.01,5]tridecane copper(II) cluster, that is, (Cu[N{CH (CH2Ph)CH2OH}{CH2(4? Br? C6H3O)}{CH2(2? CHO? 4? Me? C6H2O)}])2 ( 2 ) is described. The compounds are characterized by elemental analyses, Fourier transform infrared (FT‐IR) spectroscopy, mass spectrometry and single‐crystal X‐ray crystallography (for 2 ). The compound 2 is the first example of chiral pseudo‐copper(II)atrane in which three unsymmetrical arms (two phenolic and a chiral ethanolic arm) are fused via Cu? N transannular bond. The free ? CHO group present in one of the tricyclic arms of the 2 is tested as a linker to load it on 3‐aminopropyltriethoxysilane‐functionalized magnetic nanosilica for catalytic applications. The loading of 2 on magnetic nanosilica through ? CHO was confirmed by FT‐IR spectroscopy, and the 2 ‐loaded magnetic nanosilica ( Fe 3 O 4 @SiO 2 /2 ) was characterized by powder X‐ray diffraction, vibrating sample magnetometry, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy and elemental mapping. The Fe 3 O 4 @SiO 2 /2 was found highly efficient, retrievable, eco‐friendly and green catalyst for obtaining β‐amino alcohols in excellent yields in an aqueous medium. Overall, present work is the first report on synthetic, structural and catalytic aspects of dichiral cluster of copper(II)atrane possessing unsymmetrical tricyclic arms. 相似文献
147.
The dioxo-uranium(VI)-8-hydroxyquinoline-succinate system has been studied polarographically at constant ionic strength (μ = 0.6 M KCl) in aqueous alcohol (7 : 3) at different temperatures. The reduction of the simple and mixed complexes is reversible and diffusion controlled. The DeFord-Hume and Schaap-McMaster methods have been applied in the determination of composition and stability constants of the simple and mixed complexes respectively. The thermodynamic parameters ΔG, ΔH and ΔS have also been calculated. 相似文献
148.
Investigations on isochronal annealing behaviour of /n, / activated56Mn recoils in crystalline potassium and ammonium permanganates have given different results indicating a varying degree of sensitivity of the samples to recoil annealing. The presence of ammonium ion in ammonium permanganate shows the reduction of recoil species during annealing. Vand-Primak model has been utilized to deduce the kinetic behaviour by which the energy of activation is found to be 1.1 and 1.2 eV for KMnO4 and NH4MnO4, respectively. Furthermore, the present work reveals the role of defects in the transient reactions of the lattice stable precursors and hence the mechanism of the recoil reactions. 相似文献
149.
Nandy JP Rakic B Sarma BV Babu N Lefrance M Enright GD Leek DM Daniel K Sabourin LA Arya P 《Organic letters》2008,10(6):1143-1146
We report here a practical, enantioselective synthesis of benzofuran-derived, cyclic trans-beta-amino acid scaffold. In two cases, tricyclic derivatives having six- and eight-membered unsaturated lactams were obtained from this versatile scaffold. To explore the biological applications, these compounds were subjected to cell-based assays, using NIH3T3 mouse cells to examine their potency as cell motility inhibitors and identified 18 as a potent cell motility inhibitor (IC50 approximately 40 microM in chamber cell migration assay). 相似文献
150.
Strong light-matter coupling offers a unique way to control chemical reactions at the molecular level. Here, we compare the solvent effect on an ester solvolysis process under cooperative vibrational strong coupling (VSC). Three reactants, para-nitrophenylacetate, 3-methyl-para-nitrophenylbenzoate, and bis-(2, 4-dinitrophenyl) oxalate are chosen to study the effect of VSC on the solvolysis reaction rates. Two solvents, ethyl acetate and cyclopentanone, are also considered to compare the cavity catalysis by coupling the C=O stretching band of the reactant and the solvent molecules to a Fabry-Perot cavity mode. Interestingly, both solvents enhance the chemical reaction rate of para-nitrophenylacetate and 3-methyl-para-nitrophenylbenzoate under cooperative VSC conditions. However, the resonance effect is observed at different temperatures for different solvents, which is further confirmed by thermodynamic studies. Bis-(2, 4-dinitrophenyl) oxalate doesn′t respond to VSC in either of the solvent systems due to poor overlap of reactant and solvent C=O vibrational bands. Cavity detuning and other control experiments suggest that cooperative VSC of the solvent plays a crucial role in modifying the activation free-energy of the reaction. These findings, along with other observations, cement the concept of polaritonic chemistry. 相似文献