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排序方式: 共有231条查询结果,搜索用时 31 毫秒
101.
Moorthiamma Sarathy Ganesan Kamatchi Kanmani Raja Sankaranarayanan Murugesan Banoth Karankumar Faheem Faheem Sappanimuthu Thirunavukkarasu Gauri Shetye Rui Ma Scott G. Franzblau Baojie Wan Gurusamy Rajagopal 《Journal of heterocyclic chemistry》2021,58(4):952-968
A series of novel quinoline-proline hybrids ( 11a-g ) and quinoline-proline-1,2,3-triazole hybrids ( 12-14 ) were synthesized by click chemistry based on molecular hybridization concept and were characterized by NMR, mass spectrometry, and elemental analysis. All the titled target compounds were tested for antitubercular activity by MABA and LORA methods by in vitro. Interestingly, two compounds (2R,4S)-1-((2-cyclopropyl-4-(4-fluorophenyl)-quinolin-3-yl)-methyl)-4-(4-nitrobenzamido)-N-phenylpyrrolidine-2-carboxamide ( 11b ) and (2R,4S)-1-((2-cyclopropyl-4-(4-fluorophenyl)-quinolin-3-yl)-methyl)-4-(4-fluorobenzamido)-N-phenylpyrrolidine-2-carboxamide ( 11c ) exhibited significant activity against the tested Mycobacterium tuberculosis H37Rv strain. Further, the cytotoxicity ( CC 50 ) profile of the titled compounds against the Vero cell was performed and discussed. A molecular docking study of the hit compounds ( 11b and 11c ) was also performed to find their putative binding interaction with the active site of the target proteins. Finally, in silico ADMET properties were also predicted for all the synthesized molecules to evaluate their drug-likeness behavior. 相似文献
102.
103.
Murugesan Venkatapathi 《Journal of Quantitative Spectroscopy & Radiative Transfer》2012,113(13):1705-1711
The altered spontaneous emission of an emitter near an arbitrary body can be elucidated using an energy balance of the electromagnetic field. From a classical point of view it is trivial to show that the field scattered back from any body should alter the emission of the source. But it is not at all apparent that the total radiative and non-radiative decay in an arbitrary body can add to the vacuum decay rate of the emitter (i.e.) an increase of emission that is just as much as the body absorbs and radiates in all directions. This gives us an opportunity to revisit two other elegant classical ideas of the past, the optical theorem and the Wheeler–Feynman absorber theory of radiation. It also provides us alternative perspectives of Purcell effect and generalizes many of its manifestations, both enhancement and inhibition of emission. When the optical density of states of a body or a material is difficult to resolve (in a complex geometry or a highly inhomogeneous volume) such a generalization offers new directions to solutions. 相似文献
104.
This paper presents results on the combined effect of thermo‐solutal buoyancy forces on the recirculatory flow behavior in a horizontal channel with backward‐facing step and the ensuing impact on heat and mass transfer phenomena. The governing equations for double diffusive mixed convection are represented in velocity–vorticity form of momentum equations, velocity Poisson equations, energy and concentration equations. Galerkin's finite‐element method has been employed to solve the governing equations. Recirculatory flow fields with heat and mass transfer are simulated for opposing and aiding thermo‐solutal buoyancy forces by assuming suitable boundary conditions for energy and concentration equations. The effect of Richardson number (0.1?Ri?10) and buoyancy ratio (?10?N?10) on the recirculation bubble and Nusselt and Sherwood numbers are studied in detail. For Richardson number greater than unity, distinct variations in the gradients of Nusselt number and Sherwood number with buoyancy ratio are observed for flow regimes with opposing and aiding buoyancy forces. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
105.
Complementary metal oxide semiconductor (CMOS) image sensor is a powerful tool for biosensing applications. In this present study, CMOS image sensor has been exploited for detecting glucose levels by simple photon count variation with high sensitivity. Various concentrations of glucose (100 mg dL(-1) to 1000 mg dL(-1)) were added onto a simple poly-dimethylsiloxane (PDMS) chip and the oxidation of glucose was catalyzed with the aid of an enzymatic reaction. Oxidized glucose produces a brown color with the help of chromogen during enzymatic reaction and the color density varies with the glucose concentration. Photons pass through the PDMS chip with varying color density and hit the sensor surface. Photon count was recognized by CMOS image sensor depending on the color density with respect to the glucose concentration and it was converted into digital form. By correlating the obtained digital results with glucose concentration it is possible to measure a wide range of blood glucose levels with great linearity based on CMOS image sensor and therefore this technique will promote a convenient point-of-care diagnosis. 相似文献
106.
Stephen Michael Rajesh Subbu Perumal J. Carlos Menéndez Sokkar Pandian Ramachandran Murugesan 《Tetrahedron》2012,68(27-28):5631-5636
An environmentally friendly approach to the diastereoselective synthesis of trans-4-oxo-3-aryl-3,4-dihydro-2H-furo[3,2-c]coumarin-2-carbonitriles, trans-2-benzoyl-3-(aryl)-2H-furo[3,2-c]chromen-4(3H)-ones and trans-ethyl-4-oxo-3-(aryl)-3,4-dihydro-2H-furo[3,2-c]chromene-2-carboxylates in good yields is described. The method is based on the sequential multicomponent reactions of 4-hydroxycoumarin, aromatic aldehydes and in situ generated cyanomethylpyridinium, phenacylpyridinium/(2-ethoxy-2-oxoethyl)pyridinium ylides, in the presence of the ionic liquid [BMIm]OH, which functions both as a catalyst and the reaction medium. 相似文献
107.
Murugesan S Kearns P Stevenson KJ 《Langmuir : the ACS journal of surfaces and colloids》2012,28(13):5513-5517
A facile room-temperature electrochemical deposition process for germanium sulfide (GeS(x)) has been developed with the use of an ionic liquid as an electrolyte. The electrodeposition mechanism follows the induced codeposition of Ge and S precursors in ionic liquids generating GeS(x) films. The electrodeposited GeS(x) films were characterized by scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) and Raman and X-ray photoelectron spectroscopy (XPS). An aqueous-based Ag doping method was used to dope electrochemically grown GeS(x) films with controlled doping compared to the conventional process, which can be used in next-generation solid-state memory devices. 相似文献
108.
Zong‐Zhan Lu Dr. Chung‐Chou Lee Dr. Murugesan Velayudham Li‐Wei Lee Dr. Jing‐Yun Wu Ting‐Shen Kuo Prof. Dr. Kuang‐Lieh Lu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(49):15714-15721
The high‐yielding self‐assembly of three neutral rhenium(I) rectangles, [Re2(CO)6(L)(bpe)]2 ( 1 a , L=2,2′‐biimidazolate (biim); 1 b , L=2,2′‐bisbenzimidazolate (bbim); 1 c , L=2,2′‐bis(4,5‐dimethylimidazolate) (bdmim); bpe=trans‐1,2‐bis(4‐pyridyl)ethylene), under hydrothermal conditions is described. The rectangles were structurally characterized by spectroscopic techniques and further confirmed by single‐crystal X‐ray diffraction. Upon irradiation with a Hg lamp at 365 nm, the bpe ligands of rectangles 1 a and 1 b underwent [2+2] photocycloaddition reactions to produce [{(Re(CO)3)2L}2(4,4′‐tpcb)2] ( 2 a , L=biim; 2 b , L=bbim; 4,4′‐tpcb=1,2,3,4‐tetrakis(4‐pyridyl)cyclobutane) through a single‐crystal‐to‐single‐crystal (SCSC) transformation. However, rectangle 1 c , which contained methyl groups on the 2,2′‐biimidazolate ligand, failed to undergo cycloaddition, even after prolonged irradiation. This result indicates that the light‐induced cycloaddition reaction can be preferentially controlled by the remote regulatory substituents, which are attached onto the same backbone of the rectangle complex. This transformation is the first reported utilization of a remote ancillary regulatory ligand that is covalently attached onto a coordination compound to control the [2+2] cycloaddition reaction. 相似文献
109.
Paul BT Babu MS Santhoshkumar TR Karunagaran D Selvam GS Brown K Woo T Sharma S Naicker S Murugesan R 《Journal of photochemistry and photobiology. B, Biology》2009,94(1):38-44
Two novel cyclohexane-1,2-diamino and N,N dimethyl amino-propyl substituted hypocrellin B derivatives, abbreviated as CHA2HB and DMAHB, respectively were synthesized. These derivatives exhibited enhanced absorption in phototherapeutic window. Photodynamic action of these derivatives, investigated using optical and electron spin resonance methods, depended on both Type I and Type II mechanisms. Gel electrophoresis indicated 1O2/O2(.-) mediated DNA damage. CHA2HB displayed 20 fold increase in light dependent cytotoxicity on colon cancer cell line (HCT 116) than the well-known hypocrellin B (HB). The light induced, LD(50) values for CHA2HB and DMAHB were found to be 0.1 microM and 1.5 microM, respectively. The singlet oxygen generating efficiency followed the order HB>CHA(2)HB>DMAHB. But, the enhanced red absorption as well as the hydrophilicity renders the CHA2HB a better photodynamic therapeutic agent. 相似文献
110.
Ponnusamy Sami Natarajan Mariselvi Kandasamy Venkateshwari Murugesan Vairalakshmi Arunachalam Sarathi Kasi Rajasekaran 《Transition Metal Chemistry》2010,35(5):563-570
The kinetics of reduction of heteropoly 11-tungstovanadophosphate, [PVVW11O40]4−, (HPA1) and heteropoly 10-tungstodivanadophosphate, [PVVVVW10O40]5−, (HPA2) by thiourea has been investigated in HClO4/phthalate/acetate buffer solutions spectrophotometrically at 25 °C in aqueous medium. The stoichiometry of the reaction is
1:1 in both cases. The HPAs are converted into the corresponding one-electron reduced heteropoly blues, namely, [PVIVW11O40]5− and [PVIVVVW10O40]6−, and thiourea is oxidised to formamidine disulphide. The reaction shows first-order dependence in both [HPA] and [thiourea]
at constant pH. The rate–pH profile shows the participation of both the neutral and deprotonated forms of thiourea in the
reaction. The reaction proceeds through an outer sphere electron transfer mechanism in which activation-controlled electron
transfer is the rate-determining step. Self-exchange rate constants for the couples [PVVW11O40]4−/[PVIVW11O40]5−, [PVVVVW10O40]5−/[PVIVVVW10O40]6− and H2NCSNH2/H2NCS·+NH2 have been evaluated by Marcus theory. 相似文献