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121.
122.
Dr. Prabhakaran Rajasekar Abinash Swain Prof. Dr. Gopalan Rajaraman Prof. Dr. Ramamoorthy Boomishankar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(39):10012-10015
The synthesis of cages with a polyradical framework remains a challenging task. Herein is reported an enantiomeric pair of quinoid-bridged polyradical tetrahedral palladium(II) cages that are stabilized by an unusual dianionic diradical form (dhbq..2−). These cages have been characterized by electron paramagnetic resonance and UV-visible spectroscopy, squid magnetometry and mass spectrometry. Single-crystal-derived X-ray investigations of the iso-structural cages built on fluoranilate linkers confirm the tetrahedral structure of the obtained radical cages. Theoretical calculations showed that the diradical state of the dhbq anions is more stable than the usual monoradical state. A weak ferromagnetic exchange between adjacent radical centers was observed in DFT studies. 相似文献
123.
Replacing a hypothetical i?+?3?→?i peptide H-bond in a disordered pentapeptide, that lacks any helicogenic Cα-tetrasubstituted residues, with a propyl linker and carbamylating the N-terminal nitrogen constrains it in the elusive 310-helical structure with high helicity and stability under varying conditions of temperature and pH, confirmed by NMR and CD analyses. 相似文献
124.
Settu Loganathan Kuppusamy Selvam Muthugounder Subaramanian Shivakumar Sengottayan Senthil-Nathan Prabhakaran Vasantha-Srinivasan Dhakshinamoorthy Gnana Prakash Sengodan Karthi Fahad Al-Misned Shahid Mahboob Ahmed Abdel-Megeed Aml Ghaith Patcharin Krutmuang 《Molecules (Basel, Switzerland)》2022,27(22)
Green synthesis of silver nanoparticles (AgNPs) has gained greater interest among chemists and researchers in this current scenario. The present research investigates the larvicidal and anti-proliferation activity of AgNPs derived from Knoxia sumatrensis aqueous leaf extract (K. sumatrensis-ALE) as a potential capping and reducing candidate. The synthesized AgNPs were characterized through-UV-spectra absorption peak at 425 nm. The XRD and FT-IR studied displayed the crystalline nature and presence of functional groups in prepared samples. FE-SEM showed the hexagonal shape of NPs with the size of 7.73 to 32.84 nm. The synthesized AgNPs displayed superior antioxidant and anti-proliferative activity (IC50 53.29 µg/mL) of breast cancer cell line (MCF-7). Additionally, larvicidal activity against mosquito vector Culex quinquefasciatus larvae delivered (LC50-0.40, mg/L, and LC90-15.83) significant mortality rate post treatment with synthesized AgNPs. Overall, the present research illustrates that the synthesized AgNPs have high biological potential and present a perfect contender in the pharmacological and mosquitocidal arena. 相似文献
125.
Savithri Krishnaswamy Prabhakaran Rathinasabapathi Paulpandi Manickam Enoch Israel V. M. V. Mohan Palathurai Subramaniam 《Transition Metal Chemistry》2020,45(7):443-455
Transition Metal Chemistry - A highly sensitive and selective imidazole-based fluorescent “on–off” probe, (2-(4,5-bis((E)-4-methoxystyryl)-1H-imidazol-2-yl) phenol) (BMIP), is... 相似文献
126.
Aneesh Prabhakaran Ahmed M. Hamid Sandilya V. B. Garimella Blandina R. Valenzuela Robert G. Ewing Yehia M. Ibrahim Richard D. Smith 《Journal of the American Society for Mass Spectrometry》2018,29(2):342-351
Here we explore the combination of constant and oscillatory fields applied in a single device to affect the continuous separation and filtering of ions based on their mobilities. The device explored allows confining and manipulating ions utilizing a combination of radio frequency (rf), direct current (DC) fields, and traveling waves (TW) in a structures for lossless ion manipulations (SLIM) module. We have investigated theoretically and experimentally a concept for continuous filtering of ions based on their mobilities where ions are mobility separated and selected by passage through two regions, both of which incorporated combined TW and constant fields providing opposing forces on the ions. The SLIM module was composed of two surfaces with mirror-image arrays of electrodes and had two regions where the different TW and opposing DC fields could be applied. The filtering capabilities are determined by the applied DC gradient and the TW parameters, such as speed, amplitude, and the TW sequence (i.e., the duty cycle of the traveling wave). The effects of different parameters on the sensitivity and the ion mobility (IM) resolution of the device have been investigated. By appropriately choosing the DC gradient and TW parameters for the two sections, it is possible to transmit ions of a selected mobility while filtering out others of both higher and lower mobility. The novel device described here provides a basis for the targeted analysis of compounds based upon the continuous selection of ions according to their mobility and without the need for high electric fields or pulsed injection. 相似文献
127.
Keshri Nath Tiwari S.M. Prabhakaran Vaneet Kumar Thakar Snehal Rajendra Shintu Mathew 《Tetrahedron》2018,74(27):3596-3601
We have demonstrated three component reaction of isatin, enaminone and ethyl cyanoacetate leading to sprirooxindole scaffold without catalyst in water. The synthetic protocol has several advantages like wide substrate scope, atom-economy and operationally simple experimental procedures which provides rapid access to library of compounds. The mechanistic details of the reaction has been investigated during the course of study. 相似文献
128.
Saravana Kumar Jaganathan Mohan Prasath Mani Praseetha Prabhakaran Eko Supriyanto Ahmad Fauzi Ismail 《International Journal of Polymer Analysis and Characterization》2019,24(5):457-474
Scaffolds used in skin tissue engineering must mimic the native function of the extracellular matrix (ECM) and facilitate the fibroblast cell response for new tissue growth. In this study, a novel dressing scaffold based on polyurethane (PU) with sesame oil, honey, and propolis was fabricated by electrospinning. Scanning electron microscopy (SEM) images showed that the diameter of the electrospun scaffolds decreased by blending sesame oil (784?±?125.46?nm) and sesame oil/honey/propolis (576?±?133.72?nm) into the PU matrix (890?±?116.911?nm). Fourier infrared (FT-IR) and thermogravimetric (TGA) analysis demonstrated the formation of hydrogen bonds and interaction between PU and sesame oil, honey, and propolis. Contact-angle measurement indicated reduced wettability of PU/sesame oil scaffold (114?±?1.732) and improved wettability (54.33?±?1.528) in the PU/sesame oil/honey/propolis scaffold. Further, tensile tests and atomic force microscopy (AFM) analysis indicated that the fabricated composite membrane exhibited enhanced mechanical strength and reduced surface roughness compared to the pristine PU. The developed composite displayed less toxicity to the red blood cells (RBC’s) compared to the pristine PU. Cytotoxicity assay showed enhanced cell viability of HDF in electrospun scaffolds than pristine PU after 72?h culture. These enhanced properties of the developed scaffolds suggest the potential of utilizing them in skin tissue engineering. 相似文献
129.
Birefringent composite models are fabricated using epoxy resin reinforced with unidirectionally oriented glass fibers. The mechanical and photoelastic properties of the material at room temperature are determined. To explore the possibility of application of stress-freezing technique to birefringent composite models, the behavior and properties of this material are studied at elevated temperature (at stress-freezing temperature of the resin). The properties of the material at room and at elevated temperatures are reported. The feasibility of stress freezing glass-fiber-reinforced epoxy composites with low-fiber-volume fraction is discussed. 相似文献
130.
Keshri Nath Tiwari Mane Rajendra Uttam Puja Kumari Piyush Vatsa S. M. Prabhakaran 《合成通讯》2017,47(10):1013-1019
An efficient synthesis of acridinediones in two steps have been achieved using water as a reaction media without chromatographic purification. First step involves the reaction of dimedone with ammonium acetate to yield enaminone in water which on further reaction with various aldehydes yields acridinedione in aqueous media. The reaction merits the use of water as solvent, no additive catalyst and provides high yield of products with good purity. 相似文献