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151.
Murugan NA Kongsted J Rinkevicius Z Agren H 《Physical chemistry chemical physics : PCCP》2011,13(4):1290-1292
Based on hybrid QM/MM simulation techniques, we rationalize the spectacular solvatochromic reversal behavior observed for a stilbazolium merocyanine (SM) called Brooker's merocyanine dye. This solvatochromic reversal is attributed to a change in the solute π-electron distribution from zwitterionic to neutral following the change in solvents from polar to non polar. Based on our calculations, we suggest that a polar solvent, like water, with larger relative permittivity is influential enough to bring the change in molecular structure from neutral to zwitterionic. Our results clearly indicate that SM exists in a neutral molecular structure in non polar solvents like trichloromethane and thereby we suggest that self-aggregation of SM may not occur in this solvent. 相似文献
152.
Abstract Copolymers of p-nitrobenzyl acrylate and methyl acrylate with different feed ratios are synthesized in ethyl methyl ketone using benzoyl peroxide as a free radical initiator at 70 ± 1°C. The copolymers were characterized by IR and 1H-NMR spectroscopic techniques. Copolymer compositions were determined by 1H-NMR analysis of the polymers. The monomer reactivity ratios were determined by the application of conventional linearization methods such as Fineman–Ross and Kelen–Tüdös. Gel permeation chromatography was used for determining the molecular weights M n and M w, and the polydispersity index. The intrinsic viscosities and the thermal properties of the homo- and copolymers are also discussed. 相似文献
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154.
Poovan Shanmugavelan Murugan Sathishkumar Sangaraiah Nagarajan Alagusundaram Ponnuswamy 《中国化学快报》2014,25(1):146-148
An efficient and facile synthesis of a library of hitherto novel 1,2,3-triazolyl-N-acetyl/N-propionylpyrazoline hybrids(16 examples) in excellent yields(90%–96%) has been accomplished from easily accessible 1,2,3-triazolyl chalcone precursors. 相似文献
155.
An eco-friendly water mediated synthesis of 1,2,3-triazolyl-2- aminopyrimidine hybrids as highly potent anti-bacterial agents 总被引:1,自引:1,他引:0
Sangaraiah Nagarajan Poovan Shanmugavelan Murugan Sathishkumar Ramasamy Selvi Alagusundaram Ponnuswamy Hariharan Harikrishnan Vellasamy Shanmugaiah 《中国化学快报》2014,25(3):419-422
An elegant and efficient synthesis of novel 1,2,3-triazole fused 2-aminopyrimidine hybrids has been accomplished for the first time in the green solvent viz. water. The hybrid molecules exhibit significant anti-bacterial activity when screened against three human pathogens viz. Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumoniae. In comparison to the commercially marketed drug tetracycline, some of them are equally potent and a few are more potent. 相似文献
156.
Karuppiah Nagaraj Krishnan Senthil Murugan Pilavadi Thangamuniyandi 《Phase Transitions》2015,88(5):461-474
In this study, we report the kinetics of reduction reactions of single and double chain surfactant cobalt(III) complexes of octahedral geometry, cis-[Co(en)2(4AMP)(DA)](ClO4)3 and cis-[Co(dmp)2(C12H25NH2)2](ClO4)3 (en = ethylenediamine, dmp = 1,3-diaminopropane, 4AMP = 4-aminopropane, C12H25NH2 = dodecylamine) by Fe2+ ion in dipalmitoylphosphotidylcholine (DPPC) vesicles at different temperatures under pseudo first-order conditions. The kinetics of these reactions is followed by spectrophotometry method. The reactions are found to be second order and the electron transfer is postulated as outer sphere. The remarkable findings in the present investigation are that, below the phase transition temperature of DPPC, the rate decreases with an increase in the concentration of DPPC, while above the phase transition temperature the rate increases with an increase in the concentration of DPPC. The main driving force for this phenomenon is considered to be the intervesicular hydrophobic interaction between vesicles surface and hydrophobic part of the surfactant complexes. Besides, comparing the values of rate constants of these outer-sphere electron transfer reactions in the absence and in the presence of DPPC, the rate constant values in the presence of DPPC are always found to be greater than in the absence of DPPC. This is ascribed to the double hydrophobic fatty acid chain in the DPPC that gives the molecule an overall tubular shape due to the intervesicular hydrophobic interaction between vesicles surface and hydrophobic part of the surfactant complexes more suitable for vesicle aggregation which facilitates lower activation energy, and consequently higher rate is observed in the presence of DPPC. The activation parameters (ΔS# and ΔH#) of the reactions at different temperatures have been calculated which corroborate the kinetics of the reaction. 相似文献
157.
Murugesan Sasikumar Milind D. Nikalje Murugan Muthukrishnan 《Tetrahedron: Asymmetry》2009,20(24):2814-2817
Enantiopure (R)-mexiletine was prepared in a simple and practical way using hydrolytic kinetic resolution method of terminal epoxide by Jacobsen’s catalyst. High enantiomeric purity (98% ee) was achieved and the method is well amenable to industrial scale-up. 相似文献
158.
159.
160.
Veeramani Murugan Ponnusamy Parasuraman Jeyasigamani F. A. Selvin Michael M. Gromiha Kazuhiko Fukui 《Journal of carbohydrate chemistry》2017,36(2-3):111-128
In the present study, the hydroxyl groups at the C4 and C7 positions of sialic acid and C6 position of galactose in Neu5Acα(2–3)Gal (N23G) and the hydroxyl groups at the C8 position of sialic acid and C3 and C4 positions of galactose in Neu5Acα(2–6)Gal (N26G) were substituted with fluorine atoms, respectively. Molecular dynamics simulations of 100 ns duration were carried out to investigate the structural and dynamical behavior of H1 bound with the tri-fluorinated N23G and N26G (FN23G and FN26G). Based on energy analysis, it was concluded that FN26G should be a better binder for hemagglutinin (H1) than FN23G and it might act as an inhibitor for influenza. 相似文献