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Trinadh Kaicharla Tony Roy Manikandan Thangaraj Dr. Rajesh G. Gonnade Dr. Akkattu T. Biju 《Angewandte Chemie (International ed. in English)》2016,55(34):10061-10064
Lewis acid‐catalyzed reactions of 2‐substituted cyclopropane 1,1‐dicarboxylates with 2‐naphthols is reported. The reaction exhibits tunable selectivity depending on the nature of Lewis acid employed and proceed as a dearomatization/rearomatization sequence. With Bi(OTf)3 as the Lewis acid, a highly selective dehydrative [3+2] cyclopentannulation takes place leading to the formation of naphthalene‐fused cyclopentanes. Interestingly, engaging Sc(OTf)3 as the Lewis acid, a Friedel–Crafts‐type addition of 2‐naphthols to cyclopropanes takes place, thus affording functionalized 2‐naphthols. Both reactions furnished the target products in high regioselectivity and moderate to high yields. 相似文献
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Thangaraj Anand Gandhi Sivaraman Murugan Iniya Ayyanar Siva Duraisamy Chellappa 《Analytica chimica acta》2015
Chemosensors based on aminobenzohydrazide Schiff bases bearing pyrene/anthracene as fluorophores have been designed and synthesized for F− ion recognition. The addition of fluoride ions to the receptors causes a dramatically observable colour change from pale yellow to brown/red. 1H NMR studies confirm that the F− ion facilitates its recognition by forming hydrogen bond with hydrogens of amide and amine groups. Moreover these sensors have also been successfully applied to detection of fluoride ion in commercial tooth paste solution. 相似文献
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Thangaraj Arasakumar Sadasivam Mathusalini Athar Ata Ramasamy Shankar Subashini Gopalan Krishnasamy Lakshmi Pandiyarajan Sakthivel Palathurai Subramaniam Mohan 《Molecular diversity》2017,21(1):37-52
A series of 4-quinolone-3-carboxylic acid-containing spirooxindole-pyrrolidine derivatives was synthesized via multicomponent 1,3-dipolar cycloaddition reactions of azomethine ylides with new (E)-4-oxo-6-(3-phenyl-acryloyl)-1,4-dihydroquinoline-3-carboxylic acids in good yields with high regioselectivity. The cycloadducts were characterized by analytical and spectral data including \(^{1}\hbox {H}\), \(^{13}\hbox {C}\), 2D NMR and mass spectroscopy. The structure of one of the compounds (8a) was investigated theoretically by computational techniques. DFT studies support the proposed mechanism for this cycloaddition reaction. Furthermore, antibacterial activities of the new compounds were evaluated against Gram-positive and Gram-negative bacterial strains. Compounds 8f, 8m and 8p showed potent inhibition activities against selected bacteria. The in vitro cytotoxicity of spirooxindole derivatives (8a–r) was evaluated against MCF-7 breast cancer cell line. Among the various compounds tested, compound 8f \((\hbox {IC}_{50} = 18.35~\upmu \hbox {M})\) showed significant cytotoxic activity compared to the standard drug doxorubicin \((\hbox {IC}_{50 }= 15.00~\upmu \hbox {M})\). 相似文献
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P. Suresh S. Janarthanan R. Sugaraj Samuel A. Jestin Lenus K. Thangaraj 《Journal of Thermal Analysis and Calorimetry》2014,115(1):339-343
Nonlinear optical single crystal l-tryptophan hydrogen selenite (LTHS) has been synthesized by slow evaporation solution growth technique from aqueous solution at ambient temperature. The grown nonlinear optical crystals were subjected to single crystal XRD analysis to find the structure parameters. The formation of the product was confirmed from the FTIR and 1HNMR spectral analysis. The UV–Vis spectral studies showed that the cutoff wavelength for LTHS was less than 400 nm. The thermal behavior of the grown crystals was investigated from thermogravimetry and differential thermal analysis. Its nonlinear optical property has been tested by Kurtz–Perry powder technique using Nd:YAG laser, and the crystal exhibited second harmonic generation property. 相似文献
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We report the structure and optical properties of thermally evaporated BixIn25?xSe75 (0 ≤ x ≤ 7) films by using X-ray diffraction and optical spectroscopic techniques. The as-prepared samples were found to be amorphous by X-ray diffraction while the crystallization of Se, In2Se3 and Bi2Se3 phases has been observed upon annealing the films at 440 K. The enhancement in the main diffraction peak intensity was accepted as the increase in the crystalline character for the devitrified films with Bi content. The addition of 5 at.% of Bi results in the large change in the electrical parameters due to the carrier type reversal in the as-prepared samples. The red shift in the absorption edge along with a decrease in the transmittance has been observed for the as-prepared samples. The inverse relationship between optical gap and the tailing parameter (except x = 1) were observed with the increase in Bi content. The optical gap was found to increase up to x ≤ 1 and thereafter, resulted in the decrease in it for the thermally annealed samples. These results have been discussed in conjunction with the structural relaxation and impurity mediated heterogeneous crystallization of the film network. 相似文献
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Radhakrishnan Mahesh Sourabh Mundra Thangaraj Devadoss Lakshmi P. Kotra 《Arabian Journal of Chemistry》2019,12(7):1436-1446
The cysteine protease, falcipain-2 is an important drug target in human malaria parasite Plasmodium falciparum. A new series of 2-(4-(substituted benzoyl)-1,4-diazepan-1-yl)-N-phenylacetamide derivatives 5(a–t) were designed as per pharmacophoric requirements of falcipain-2 inhibitors using ligand-based approach. The target compounds were synthesized from the key intermediate, 2-(1,4-Diazepan-1-yl)-N-phenylacetamide, by coupling it with appropriate carboxylic acids using carbodiimide chemistry. Structural features of target compounds were characterized by spectral data (1H NMR, and mass) and elemental analyses. The purity of the final compounds was confirmed by HPLC. The compounds were tested for their in vitro falcipain-2 inhibitor activity on recombinant falcipain-2 enzyme. Five compounds 5b, 5g, 5h, 5j, 5k showed good inhibitory activity (>60%), against falcipain-2 at 10 μM concentration, and fifteen compounds showed weak to moderate inhibitor activity. Compound 5g, the most potent compound from this series showed 72% inhibition at 10 μM concentrations. 相似文献
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P. Kumar J. Kumar M. Ahmad R. Thangaraj 《Applied Physics A: Materials Science & Processing》2008,90(3):469-473
Electrical and photoelectrical measurements have been performed on SnxSb20Se70-x (8≤x≤16) glassy films. The dc activation energy, optical gap and photoconduction parameters show a typical variation near
x=10 composition indicating the occurrence of a rigidity percolation threshold in the present system. The photosensitivity
increases with the increase in Sn content up to x=14 and an abrupt decrease for x=16 composition. Negative photoconductivity
region have been observed in the higher temperature side for samples with x=10 and 16. This system belongs to the type II
category of photoconductors. The results are explained on the basis of a change in the density of localized states present
in the mobility gap with the change in the composition.
PACS 71.20.Nr; 72.20.-I; 78.66.Jg; 81.05.Gc; 73.50.Pz 相似文献
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We have synthesized a new probe 5-((anthracen-9-ylmethylene) amino)quinolin-10-ol (ANQ) based on anthracene platform. The probe was tested for its sensing behavior toward heavy metal ions Hg2+, Pb2+, light metal Al3+ ion, alkali, alkaline earth, and transition metal ions by UV–visible and fluorescent techniques in ACN/H2O mixture buffered with HEPES (pH 7.4). It shows high selectivity toward sensing Pb2+/Al3+ metal ions. Importantly, 10-fold and 5- fold fluorescence enhancement at 429 nm was observed for probe upon complexation with Pb2+ and Al3+ ions, respectively. This fluorescence enhancement is attributable to the prevention of photoinduced electron transfer. The photonic studies indicate that the probe can be adopted as a sensitive fluorescent chemosensor for Pb2+ and Al3+ ions. 相似文献
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M. Palanisamy K. Thangaraj R. Gobinathan P. Ramasamy 《Crystal Research and Technology》1986,21(7):853-857
The effect of particle size on the ice nucleating behaviour of AgI-AgBr-CuI system has been studied for the first time. Six samples of different molar ratios and five sizes in each sample are considered in the present study. It is found that the nucleation temperature is the highest for particle size in the range of 60 ± 5um. 相似文献