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21.
M. Jabeen S. Ali S. Shahzadi M. Shahid Q. M. Khan S. K. Sharma K. Qanungo 《Journal of the Iranian Chemical Society》2012,9(3):307-320
Homobimetallic complexes with oxygen and sulphur donor ligand have been synthesized at room temperature under stirring conditions using R2SnCl2 (R?=?Me, n-Bu) and R3SnCl (R?=?Me, n-Bu, Ph) in 1:1 molar ratio. The synthesized complexes have been characterized by elemental analysis, IR and multinuclear NMR (1H, 13C) spectroscopy. These complexes have also been screened for their biological activities. IR data show that the ligand acts in a bidentate manner and exhibits trigonal bipyramidal geometry in solid state which is also confirmed by semi-empirical study. NMR data show that reported complexes exhibit tetrahedral geometry in solution. Results of antimicrobial screening activities indicated that complexes (6) and (7) are very effective antibacterial and antifungal agents, respectively, and they might indeed be a potential source of antimicrobial agents, while the complex (3) exhibits significant free radical scavenging ability with lower IC50 value of 99.47?±?1.2???g/mL. Results of cytotoxicity/haemolytic activity showed the significant value of % haemolysis for complex (7) (18.101?±?2.3), while complex (4) was found to be least cytotoxic (5.733?±?1.0). Only a few colonies are observed in mutagenicity testing by Ames test. 相似文献
22.
Samanta S Sengupta K Mittra K Bandyopadhyay S Dey A 《Chemical communications (Cambridge, England)》2012,48(61):7631-7633
An iron porphyrin catalyst with four electron donor groups is reported. The porphyrin ligand bears a distal hydrogen bonding pocket which inverts the normal axial ligand binding selectivity exhibited by porphyrins bearing sterically crowded distal structures. This catalyst specifically reduces O(2) by four electrons under both fast and slow electron fluxes at pH 7. 相似文献
23.
Paras Ram Anupam Bhandari Kushal Sharma 《Journal of magnetism and magnetic materials》2010,322(21):3476-3480
The effect of magnetic field-dependent viscosity on the revolving axi-symmetric steady flow of ferrofluid in a disc is investigated by solving the boundary layer equations using Neuringer-Rosenweig model. Besides numerically calculating the velocity components and pressure for different values of magnetic field-dependent viscosity with variation in dimensionless parameter α (Karman’s parameter), we also have calculated the thickness of the boundary layer and the total volume flowing outward the z-axis. Here, the solutions of non-linear differential equations are obtained in the form of asymptotic series. 相似文献
24.
N. Tabassam S. Ali S. Shahzadi M. Shahid M. Abbas Q. M. Khan S. K. Sharma K. Qanungo 《Russian Journal of General Chemistry》2013,83(12):2423-2437
Seven different organotin(IV) complexes have been synthesized by reacting 2-ethylanilinocarbonylpropenoic acid with R2SnCl2/R3SnCl under reflux conditions. The organotin(IV) complexes along with ligand have been characterized by different techniques including elemental analysis, FT-IR and multinuclear NMR (1H and 13C). IR data show that complexation occurs through -COO site and the ligand is bidentate which is also confirmed by the semi-empirical quantum-mechanical study. 1H and 13C NMR data confirm the tetrahedral geometry of complexes in solution. The complexes as well as the ligand were also checked for various 相似文献
25.
Kannan B Marin MA Shrestha K Higgins DA Collinson MM 《Journal of chromatography. A》2011,1218(52):9406-9413
A simple, elegant method for the formation of a continuous stationary phase gradient for use in chromatographic separations is described. Its applicability to separation science is demonstrated using thin-layer chromatography as a test case. Gradient stationary phases were formed on activated High Performance Thin-Layer Chromatography (HP-TLC) plates using a newly developed methodology termed "controlled rate infusion". Specifically, the SiOH groups on the activated HP-TLC plates were reacted with 3-aminopropyltriethoxysilane (APTEOS) in a time dependent fashion by using a programmable syringe pump to control the rate of APTEOS infusion into the deposition reservoir. The shape (profile) of the gradient was controlled by the rate of infusion and imaged by taking advantage of the concentration-dependent color formation reaction between amine groups and ninhydrin. The advantages of such gradients in optimizing the retention and separation of various components in different mixtures were illustrated using mixtures of (1) four weak acids and bases and (2) three widely used over-the-counter drugs. The separation of the individual components on the gradient stationary phase was clearly improved relative to those on either traditional normal-phase TLC plates or uniformly amine-modified TLC plates. Precise control over component retention and separation was also demonstrated by strategically modifying the steepness of the gradient. 相似文献
26.
Dominic F. Brightwell Giada Truccolo Dr. Kushal Samanta Elliott J. Fenn Prof. Simon J. Holder Dr. Helena J. Shepherd Dr. Chris S. Hawes Dr. Aniello Palma 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(66):e202202368
The ability to use bio-inspired building blocks in the assembly of novel supramolecular frameworks is at the forefront of an exciting research field. Herein, we present the first polyproline helix to self-assemble into a reversibly porous, crystalline, supramolecular peptide framework (SPF). This framework is assembled from a short oligoproline, adopting the polyproline II conformation, driven by hydrogen-bonding and dispersion interactions. Thermal activation, guest-induced dynamic porosity and enantioselective guest inclusion have been demonstrated for this novel system. The principles of the self-assembly associated with this SPF will be used as a blueprint allowing for the further development of helical peptide linkers in the rational design of SPFs and metal-peptide frameworks. 相似文献
27.
Kushal D. Bhatte Krishna M. Deshmukh Yogesh P. Patil Dinesh N. Sawant Shin-Ichiro Fujita Masahiko Arai Bhalchandra M. Bhanage 《Particuology》2012,10(1):140-143
Environmentally benign one-pot protocol is used in the synthesis of silver nanoparticles (AgNPs) in powder form, involving the reduction of silver nitrate in the presence of fully hydrolyzed polyvinyl alcohol (PVA) as stabilizer by hydrogen (H2) as reducing agent in aqueous medium. Fully hydrolyzed biodegradable PVA has extremely low cytotoxicity, making it a favorable stabilizer from green perspective. In the present methodology, essentially naked silver nanoparticles are obtained in good yield. The prepared silver nanoparticles were characterized by TEM, XRD, EDAX, UV–Vis spectroscopy and DLS histogram, and studied for its activity as a recyclable catalyst for synthesis of different enaminones. 相似文献
28.
Kushal C. Lekhok Debajyoti Bhuyan Dipak Prajapati Romesh C. Boruah 《Molecular diversity》2010,14(4):841-846
An environmentally friendly and highly efficient procedure for the preparation of quinolines and fused polycyclic quinolines
has been developed by a simple Friedlander annulation reaction of 2-aminoaryl ketone with carbonyl compounds in presence of
zinc triflate under microwave irradiation and solvent-free conditions. The reaction also proceeds effectively when In(OTf)3 was used in lieu of Zn(OTf)2 as the catalyst. The catalyst can be recovered after the reaction and reused efficiently in subsequent runs. 相似文献
29.
Kushal D. Bhatte Dinesh N. Sawant Krishna M. Deshmukh Bhalchandra M. Bhanage 《Particuology》2012,10(3):384-387
A novel approach for additive free synthesis of nanocrystalline magnesium hydroxide (MH) and magnesium oxide (MgO) using microwave technique is herein reported. Use of 13-propanediol as a solvent played multiple roles circumventing the additional requirement of any extraneous species such as base and other capping agents. The prepared nanomaterials were well characterised using TEM, XRD, EDAX, Raman spectroscopy and FT-IR analysis. 相似文献