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排序方式: 共有716条查询结果,搜索用时 31 毫秒
1.
Megha Sen Chowdhury Dr. Selcuk Gumus Dr. Sanchari Dasgupta Dr. Ishani Majumder Dr. Abir Bhattacharya Dr. Debasis Das Dr. Jayanta Mukhopadhyay Dr. Debosreeta Bose Dr. Saumya Dasgupta Dr. Yuksel Akinay Dr. Madhumita Mukhopadhyay 《ChemistryOpen》2022,11(6):e202200033
We report, for the first time, a detailed crystallographic study of the supramolecular arrangement for a set of zinc(II) Schiff base complexes containing the ligand 2,6-bis((E)-((2-(dimethylamino)ethyl)imino)methyl)-4-R-phenol], where R=methyl/tert-butyl/chloro. The supramolecular study acts as a pre-screening tool for selecting the compartmental ligand R of the Schiff base for effective binding with a targeted protein, bovine serum albumin (BSA). The most stable hexagonal arrangement of the complex [Zn − Me] (R=Me) stabilises the ligand with the highest FMO energy gap (ΔE=4.22 eV) and lowest number of conformations during binding with BSA. In contrast, formation of unstable 3D columnar vertebra for [Zn − Cl] (R=Cl) tend to activate the system with lowest FMO gap (3.75 eV) with highest spontaneity factor in molecular docking. Molecular docking analyses reported in terms of 2D LigPlot+ identified site A, a cleft of domains IB, IIIA and IIIB, as the most probable protein binding site of BSA. Arg144, Glu424, Ser428, Ile455 and Lys114 form the most probable interactions irrespective of the type of compartmental ligands R of the Schiff base whereas Arg185, Glu519, His145, Ile522 act as the differentiating residues with ΔG=−7.3 kcal mol−1. 相似文献
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3.
Debabrata Chatterjee Namita Jaiswal Jagadeesh C. Bose K Ram Balak Mahato Diptendu Bhattacharyya 《Journal of Coordination Chemistry》2015,68(17-18):3229-3235
Reaction of [RuIII(EDTA)(CyS)]2? (edta4? = ethylenediaminetetraacetate; CySH = cysteine) with molecular oxygen (O2) has been studied as a function of pH (4.0–8.0) and cysteine concentration (0.2–2.0 mM) at room temperature (25 °C). Biological activities of the [Ru(EDTA)]/CySH/O2 system pertaining to cleavage of supercoiled plasmid DNA to its nicked open circular form has been explored in this work. Results are discussed in regard to the reaction of the ruthenium(III)-complex with molecular oxygen) and a working mechanism is proposed for the biological activities of the ruthenium(III)-complex in the presence of O2. 相似文献
4.
Direct Synthesis of Controlled‐Size Nanospheres inside Nanocavities of Self‐Organized Photopolymerizing Soft Oxometalates [PW12O40]n (n=1100–7500) 下载免费PDF全文
The unusual self‐assembly of {(BMIm)2(DMIm)[PW12O40]}n (n=1100–7500) (BMIm=1‐butyl‐3‐methylimidazolium, DMIm=3,3′‐dimethyl‐1,1′‐diimidazolium) soft oxometalates (SOMs) with controlled size and a hollow nanocavity was exploited for the photochemical synthesis of polymeric nanospheres within the nanocavity of the SOM. The SOM vesicle has been characterized by using several techniques, including dynamic light scattering (DLS), static light scattering (SLS), attenuated total reflection (ATR) IR spectroscopy, Raman spectroscopy, microscopy, and zeta‐potential analysis. The self‐assembly and stabilization of this soft‐oxometalate vesicle has been shown by means of counter‐ion condensation. The immediate implication of such stabilization—the variation of the dielectric constant with the hydrodynamic radius of the vesicle—has been used to synthesize vesicles of controlled size. Such vesicles of varying size have been used as templates for polymerization reactions that produce polymeric spheres of controlled size. Direct evidence shows that the SOM behaves as a model heterogeneous catalytic system. Such surfactant‐ and initiator‐free photochemical synthetic routes for obtaining uniform latex spheres could be used in the making of optical bandgap materials, inverse opals, and paints. 相似文献
5.
The total synthesis of oxacalothrixins, an isostere of biologically important carbazoloquinone alkaloid, calothrixin B was achieved from 2-acetyl-3-methylbenzofuran. An iodine/TBHP-mediated oxidative cyclization of benzofuranyl-enamine has been employed as a key step to synthesize, the crucial intermediate 1-hydroxy dibenzofurancarbaldehyde. The latter upon reductive cyclization followed by PIDA-mediated oxidation furnished oxacalothrixin B and its analogues. 相似文献
6.
Planar solidification of a warm flowing liquid with the convective heat transfer to the growing solid layer, has been analysed for the boundary conditions of constant temperature, constant heat flux and convective heat flux at the surface respectively. The mathematical formulation of the problem resulted in a coupled set of two differential equations in temperature and solid thickness as function of position, time and the problem parameters. Analytical expressions for the temperature distribution within the growing solid layer, the rate of solidification and the solidification time are obtained. The perturbation techniques employed here is simple and straight forward in contrast with the earlier techniques. Good agreement between the experimental results and the present solutions is obtained for the convective heat flux boundary condition. The results of this analysis are useful in the design and analysis of experiments dealing with freezing/melting in one dimension. The role of the parameter Stefan number which is small for phase change materials, is discussed in context with the storage of thermal energy. 相似文献
7.
Dr. Mostakim SK Dr. Soumitra Barman Shounik Paul Ratnadip De Dr. S. S. Sreejith Dr. Helge Reinsch Dr. Maciej Grzywa Dr. Norbert Stock Prof. Dr. Dirk Volkmer Dr. Shyam Biswas Prof. Dr. Soumyajit Roy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(12):4098-4107
A Zr-based metal-organic framework has been synthesized and employed as a catalyst for photochemical carbon dioxide reduction coupled with water oxidation. The catalyst shows significant carbon dioxide reduction property with concomitant water oxidation. The catalyst has broad visible light as well as UV light absorption property, which is further confirmed from electronic absorption spectroscopy. Formic acid was the only reduced product from carbon dioxide with a turn-over frequency (TOF) of 0.69 h−1 in addition to oxygen, which was produced with a TOF of 0.54 h−1. No external photosensitizer is used and the ligand itself acts as the light harvester. The efficient and selective photochemical carbon dioxide reduction to formic acid with concomitant water oxidation using Zr-based MOF as catalyst is thus demonstrated here. 相似文献
8.
In an environmentally benign solvent-free system, oximes and hydrazones are rapidly transformed into parent carbonyl compounds using peroxymonosulfate on silica gel under microwave irradiation in good to excellent yields. 相似文献
9.
Abstract: Peroxymonosulfate ion (oxone®) was found to be an efficient oxidant in the conversion of oximes to carbonyl compounds. 相似文献
10.