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41.
Natarajan Arumugam Abdulrahman I. Almansour Raju Suresh Kumar Mohammad Altaf S.M. Mahalingam Govindasami Periyasami J. Carlos Menéndez Abdul Jaleel Mohammad Ali Al-Aizari 《Tetrahedron letters》2019,60(8):602-605
A series of structurally intriguing novel pyrrolo[3,2-c]quinolinone heterocyclic hybrids have been synthesized for the first time via a one-pot multicomponent domino reaction sequence that involves a 1,3-dipolar cycloaddition and two subsequent annulation steps. Baylis-Hillman adducts derived from various substituted benzaldehyde and methyl acrylate in presence of DABCO were used as a dipolarophiles, while the 1,3-dipole components were azomethine ylides, formed in situ from isatin derivatives and l-phenylalanine. The reaction generated five new bonds, three new rings and four contiguous stereocenters, which were created with full diastereomeric control. 相似文献
42.
Gurusamy Arumugam Jagmohan Tyagi 《Mathematical Methods in the Applied Sciences》2020,43(10):6576-6597
We establish the existence of nonnegative weak solutions to nonlinear reaction–diffusion system with cross-diffusion and nonstandard growth conditions subject to the homogeneous Neumann boundary conditions. We assume that the diffusion operators satisfy certain monotonicity condition and nonstandard growth conditions and prove that the existence of weak solutions using Galerkin's approximation technique. 相似文献
43.
Mohapatra Satyabrata Manglani Nishant Krishnan Dilmel Arumugam Ilavarasu Vijayakumar Madhavan Babu Uddagiri V. 《平面色谱法杂志一现代薄层色谱法》2014,27(4):251-254
JPC – Journal of Planar Chromatography – Modern TLC - Arnebia nobilis has gained an increasing popularity for the recently recognized various pharmacological activities. The root part... 相似文献
44.
Dr. Xingwen Yu Prof. Arumugam Manthiram 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(11):4233-4237
A unique sodium sulfide (Na2S) cathode is developed, which will allow the use of sodium‐free anodes for room‐temperature sodium–sulfur (Na–S) batteries. To overcome the “inert” nature of the Na2S, a special cathode structure is developed by spreading the multi‐walled carbon nanotube (MWCNT)‐wrapped Na2S particles onto MWCNT fabrics. Spectroscopic and electrochemical analyses reveal a series of polysulfide intermediates involved in the charge/discharge of the cell. The Na–S battery prepared in full discharge state with the Na2S/MWCNT cathode provides a remarkable capacity of 500 A h kg?1 (based on sulfur mass) after 50 cycles. 相似文献
45.
P. Laavanya K. Panchanatheswaran M. N. Arumugam S. Arunachalam 《Journal of chemical crystallography》1998,28(1):83-86
An octahedral geometry for the molecule of the title complex with very slight distortions around Co(III) is confirmed by single-crystal X-ray diffraction study. The molecular structure of the complex has been shown to contain two dodecylamine moieties in the trans orientations, two N-bonded dimethylglyoximato (DMG) groups and an uncoordinated nitrite ion. 相似文献
46.
An efficient “one-pot” method for the synthesis of substituted 1,2,3-triazole derivatives in excellent yields as single regioisomer is reported. The key transformation involves an atom-efficient tandem azidation, intramolecular [3+2]-cycloaddition and aromatization of acrylate derivatives on treatment with NaN3 in DMF under mild conditions. 相似文献
47.
Kadarkarai Murugan Jagannathan Madhavan Christina Mary Samidoss Chellasamy Panneerselvam Al Thabiani Aziz Arumugam Malathi Aruliah Rajasekar Amuthavalli Pandiyan Suresh Kumar Abdullah A. Alarfaj Akon Higuchi Giovanni Benelli 《Journal of Cluster Science》2018,29(2):337-344
Anopheles stephensi is a mosquito vector of malaria, which is still considered a relevant public health problem due to increasing outdoor transmission, growing resistance to insecticides used to target vectors, and antiplasmodial drugs as well. Thus, there is a vital need to explore novel sources of effective compounds. In this study, the hydrothermal method was used for the synthesis of bismuth oxyiodide (BiOI) nanoflakes. Furthermore, the toxicity of BiOI nanoflakes was evaluated for the first time on A. stephensi, as well as in vivo against the malaria parasite Plasmodium berghei. The synthesis of BiOI nanoflakes was confirmed by various characterization techniques, including X-ray diffraction, Fourier transform-infrared spectroscopy, field emission scanning electron microscopy and transmission electron microscopy (HR-TEM). LC50 of BiOI nanoflakes on A. stephensi were 2.263 ppm (larva I), 3.414 ppm (II), 4.956 ppm (III), 6.983 ppm (IV) and 8.605 ppm (pupae). In vivo antiplasmodial experiments conducted on P. berghei infecting albino mice showed 27.2% of chemosuppression after 4 days of treatment with 300 mg/kg/day of BiOI, a lower performance if compared to chloroquine. Overall, our results suggested that hydrothermal synthesis of BiOI nanoflakes may be considered to develop newer and safer tools for malaria vector control. 相似文献
48.
Modified High‐Nickel Cathodes with Stable Surface Chemistry Against Ambient Air for Lithium‐Ion Batteries
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Dr. Ya You Dr. Hugo Celio Jianyu Li Dr. Andrei Dolocan Prof. Dr. Arumugam Manthiram 《Angewandte Chemie (International ed. in English)》2018,57(22):6480-6485
High‐Ni layered oxides are promising next‐generation cathodes for lithium‐ion batteries owing to their high capacity and lower cost. However, as the Ni content increases over 70 %, they have a high dynamic affinity towards moisture and CO2 in ambient air, primarily reacting to form LiOH, Li2CO3, and LiHCO3 on the surface, which is commonly termed “residual lithium”. Air exposure occurs after synthesis as it is common practice to handle and store them under ambient conditions. The air exposure leads to significant performance losses, and hampers the electrode fabrication, impeding their practical viability. Herein, we show that substituting a small amount of Al for Ni in the crystal lattice notably improves the chemical stability against air by limiting the formation of LiOH, Li2CO3, LiHCO3, and NiO in the near‐surface region. The Al‐doped high‐Ni oxides display a high capacity retention with excellent rate capability and cycling stability after being exposed to air for 30 days. 相似文献
49.
Natarajan Arumugam Abdulrahman I. Almansour Raju Suresh Kumar Vaiyapuri Subbarayan Periasamy Jegan Athinarayanan Ali A. Alshatwi Periyasami Govindasami Mohammad Altaf J. Carlos Menéndez 《Tetrahedron》2018,74(38):5358-5366
A small library of novel hybrid spiroheterocycles containing spirooxindole, pyrrolidine and indole/imidazole moieties were synthesized with complete regio- and diastereoselectively in good to excellent yields from a three-component process starting from a series of variously substituted (E)-(2-nitrovinyl)benzenes, indoline-2,3-dione derivatives and l-tryptophan or l-histidine in an ionic liquid. The key step of this transformation is a 1,3-dipolar cycloaddition reaction involving a rare class of in situ-generated azomethine ylides derived from aromatic amino acids. The compounds thus synthesized were evaluated for their anticancer activity and were shown to inhibit the proliferation of FaDu cells, a human epithelial cell line isolated from a squamous cell carcinoma of the hypopharynx, via apoptotic cell death. 相似文献
50.
Sai Manoj N. V. T. Gorantla Harsha S. Karnamkkott Selvakumar Arumugam Sangita Mondal Kartik Chandra Mondal 《Journal of computational chemistry》2023,44(1):43-60
The factors/structural features which are responsible for the binding, activation and reduction of N2 to NH3 by FeMoco of nitrogenase have not been completely understood well. Several relevant model complexes by Holland et al. and Peters et al. have been synthesized, characterized and studied by theoretical calculations. For a matter of fact, those complexes are much different than real active N2-binding Fe-sites of FeMoco, which possesses a central C(4-) ion having an eight valence electrons as an μ6-bridge. Here, a series of [(S3C(0))Fe(II/I/0)-N2]n- complexes in different charged/spin states containing a coordinated σ- and π-donor C(0)-atom which possesses eight outer shell electrons [carbone, (Ph3P)2C(0); Ph3P→C(0)←PPh3] and three S-donor sites (i.e. -S-Ar), have been studied by DFT, QTAIM, and EDA-NOCV calculations. The effect of the weak field ligand on Fe-centres and the subsequent N2-binding has been studied by EDA-NOCV analysis. The role of the oxidation state of Fe and N2-binding in different charged and spin states of the complex have been investigated by EDA-NOCV analyses. The intrinsic interaction energies of the Fe−N2 bond are in the range from −42/−35 to −67 kcal/mol in their corresponding ground states. The S3C(0) donor set is argued here to be closer to the actual coordination environment of one of the six Fe-centres of nitrogenase. In comparison, the captivating model complexes reported by Holland et al. and Peter et al. possess a stronger π-acceptor C-ring (S2Cring donor, π-C donor) and stronger donor set like CP3 (σ-C donor) ligands, respectively. 相似文献