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11.
Narsimha Nagula Sudeepa Kunche Mohmed Jaheer Ravi Mudavath Sreekanth Sivan Sarala Devi Ch 《Journal of fluorescence》2018,28(1):225-241
Some novel transition metal [Cu (II), Ni (II) and Co (II)] complexes of nalidixic acid hydrazone have been prepared and characterized by employing spectro-analytical techniques viz: elemental analysis, 1H-NMR, Mass, UV–Vis, IR, TGA-DTA, SEM-EDX, ESR and Spectrophotometry studies. The HyperChem 7.5 software was used for geometry optimization of title compound in its molecular and ionic forms. Quantum mechanical parameters, contour maps of highest occupied molecular orbitals (HOMO) and lowest unoccupied molecular orbitals (LUMO) and corresponding binding energy values were computed using semi empirical single point PM3 method. The stoichiometric equilibrium studies of metal complexes carried out spectrophotometrically using Job’s continuous variation and mole ratio methods inferred formation of 1:2 (ML2) metal complexes in respective systems. The title compound and its metal complexes screened for antibacterial and antifungal properties, exemplified improved activity in metal complexes. The studies of nuclease activity for the cleavage of CT- DNA and MTT assay for in vitro cytotoxic properties involving metal complexes exhibited high activity. In addition, the DNA binding properties of Cu (II), Ni (II) and Co (II) complexes investigated by electronic absorption and fluorescence measurements revealed their good binding ability and commended agreement of Kb values obtained from both the techniques. Molecular docking studies were also performed to find the binding affinity of synthesized compounds with DNA (PDB ID: 1N37) and “Thymidine phosphorylase from E.coli” (PDB ID: 4EAF) protein targets. 相似文献
12.
Structural Chemistry - The DFT B3LYP/6–31G(d,p) approach is used to study alkene aziridination by azides through catalyzed routes involving a metal nitrenoid intermediate. The catalysts... 相似文献
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Venugopal D. V. R. Karteek Rao Amperayani Uma Devi Parimi Sastry Y. N. Aruna Lakshmi K. Tarak Ramji M. Shiralgi Y. 《Research on Chemical Intermediates》2017,43(10):5755-5778
Research on Chemical Intermediates - Antibiotic-resistant penicillin binding protein (PBPs) production is one of the reasons why bacteria develop resistance to β-lactam antibiotics, and this... 相似文献
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Bisphenol-A polycarbonate films were irradiated with 86 MeV swift heavy nickel ions at varying fluences, ranging from 1 × 1011 to 1 × 1013 ions cm?2, under vacuum at room temperature, to analyze the induced electrical and thermal modifications. AC conductivity measurements and UV-visible spectroscopy, Fourier transform infra-red (FTIR) spectroscopy, thermo-gravimetric analysis (TGA), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) techniques were applied to analyze the changes. A significant, exponential increase in conductivity at higher frequency was observed with the increase of nickel ion fluence. UV-visible analysis corroborated the results of the AC conductivity measurement, revealing the increase in size of the carbon clusters embedded in the polymer network, with the increase of heavy ion fluence. FTIR analysis revealed the formation of alkene and alkyne end groups at higher doses, which further supported the suggestion that the variation in electrical properties induced by the ion irradiation of the polymer was due to development of a carbonaceous phase inside the polymer due to the irradiation. Thermal analysis, i.e., TGA and DSC patterns, showed that chain-scission was the leading phenomena in the heavy ion-irradiated polycarbonate samples, resulting in degradation of their thermal stability. 相似文献
17.
Subhrakant Jena Kiran Devi Tulsiyan Dr. Rajiv K. Kar Dr. Hemanta K. Kisan Dr. Himansu S. Biswal 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(13):4373-4383
Designing a potential protein–ligand pair is pivotal, not only to track the protein structure dynamics, but also to assist in an atomistic understanding of drug delivery. Herein, the potential of a small model thioamide probe being used to study albumin proteins is reported. By monitoring the Förster resonance energy transfer (FRET) dynamics with the help of fluorescence spectroscopic techniques, a twofold enhancement in the FRET efficiency of 2-thiopyridone (2TPY), relative to that of its amide analogue, is observed. Molecular dynamics simulations depict the relative position of the free energy minimum to be quite stable in the case of 2TPY through noncovalent interactions with sulfur, which help to enhance the FRET efficiency. Finally, its application is shown by pairing thiouracils with protein. It is found that the site-selective sulfur atom substitution approach and noncovalent interactions with sulfur can substantially enhance the FRET efficiency, which could be a potential avenue to explore in the design of FRET probes to study the structure and dynamics of biomolecules. 相似文献
18.
Caroline K. Williams Amir Lashgari Nilakshi Devi Marcus Ang Ashwin Chaturvedi Pranita Dhungana Prof. Jianbing Jimmy Jiang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(20):6240-6246
In this work, the electrocatalytic reduction of dichloromethane (CH2Cl2) into hydrocarbons involving a main group element-based molecular triazole-porphyrin electrocatalyst H2PorT8 is reported. This catalyst converted CH2Cl2 in acetonitrile to various hydrocarbons (methane, ethane, and ethylene) with a Faradaic efficiency of 70 % and current density of −13 mA cm−2 at a potential of −2.2 V vs. Fc/Fc+ using water as a proton source. The findings of this study and its mechanistic interpretations demonstrated that H2PorT8 was an efficient and stable catalyst for the hydrodechlorination of CH2Cl2 and that main group catalysts could be potentially used for exploring new catalytic reaction mechanisms. 相似文献
19.
Arumugam Vasudevan Gayathri Devi Gurusamy Rajkumar Kathiresan Sakthipandi Venkatachlam Rajendran Nallaiyan Rajendran Mani Rajkumar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1434-1449
Abstract Phosphate-based bioactive glasses and their glass ceramics for 47P2O5– (30.5)CaO–(22.5 ? x)Na2O–xZrO2 for different ZrO2 contents (x = 0, 1.5, 3.0, 4.5, and 6.0 mol%) were prepared through melt quenching and controlled heat treatment procedures. The amorphous nature of glasses and the presence of crystalline phases in glass ceramics were studied by means of X-ray diffraction (XRD) studies. The density, molar volume, ultrasonic velocities, attenuation, elastic constants, and microhardness of glass and glass ceramics were used to study the structural changes. The formation of hydroxyapatite layer on the surface of glasses and glass ceramics after immersion in simulated body fluid (SBF) was explored through XRD, Fourier transform infrared (FTIR), and scanning electron microscopy (SEM) analyses. The results indicate that the added ZrO2 increases the crosslink density of glasses, resulting in network stability, and also induces the formation of an apatite layer on the surface of glasses. 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. 相似文献
20.
Jai Devi Suman Kumari R. Malhotra 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):587-597
Abstract The Schiff bases derived from the condensation of 2-aminobenzothiazole derivatives and 2-hydroxy-3-methoxybenzaldehyde and their silicon(IV) complexes with the general formula R2Si(L)Cl (R = Et, Bu, Ph, L = 2-(2-hydroxy-3-methoxy) benzylideneaminobenzo-thiazole) have been synthesized. These complexes have been characterized by elemental analysis, molar conductance, and spectroscopic studies including IR and NMR (1H, 13C, and 29Si) spectroscopy. The analytical data suggest trigonal bipyramidal geometry around the silicon atom in the resulting complexes. The ligands and their organosilicon complexes have also been evaluated for in vitro antimicrobial activity against bacteria (Staphylococcus aureus, Bacillus subtilis, and Escherichia coli) and fungi (Aspergillus niger and Candida albicans). The complexes were found to be more potent as compared to the ligands. 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. 相似文献