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91.
N. Vijayan G. Bhagavannarayana K. K. Maurya S. Pal S. N. Datta R. Gopalakrishnan P. Ramasamy 《Crystal Research and Technology》2007,42(2):195-200
Single crystal of 8‐hydroxyquinoline (8HQ) having chemical formula C9H7NO, an organic nonlinear optical (NLO) material has been successfully grown by slow evaporation solution growth technique at room temperature. The crystal system has been confirmed from the powder X‐ray diffraction (PXRD) analysis. The crystalline perfection was evaluated by high resolution X‐ray diffractometry (HRXRD). From this analysis we found that the quality of the crystal is quite good. However, a very low angle (tilt angle 14 arc sec) boundary was observed which might be due to entrapping of solvent molecules in the crystal during growth. Its optical behavior has been examined by UV‐Vis. analysis, which shows the absence of absorbance between the wavelengths ranging from 400 to 1200 nm. From the thermal analysis it was observed that the material exhibits single sharp weight loss starting at 113°C without any degradation. The laser damage threshold was measured at single shot mode and the SHG behavior has been tested using Nd:YAG laser as a source. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
92.
Dr. Priyankar Paira Mun Juinn Chow Gopalakrishnan Venkatesan Vamsi Krishna Kosaraju Dr. Siew Lee Cheong Karl‐Norbert Klotz Dr. Wee Han Ang Assoc.Prof. Giorgia Pastorin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(25):8321-8330
Human A3 adenosine receptor (hA3AR) is a membrane‐bound G protein‐coupled receptor implicated in a number of severe pathological conditions, including cancer, in which it acts as a potential therapeutic target. To derive structure–activity relationships on pyrazolo–triazolo–pyrimidine (PTP)‐based A3AR antagonists, we developed a new class of organometallic inhibitors through replacement of the triazolo moiety with an organoruthenium fragment. The objective was to introduce by design structural diversity into the PTP scaffold in order to tune their binding efficacy toward the target receptor. These novel organoruthenium antagonists displayed good aquatic stability and moderate binding affinity toward the hA3 receptor in the low micromolar range. The assembly of these complexes through a template‐driven approach with selective ligand replacement at the metal center to control their steric and receptor‐binding properties is discussed. 相似文献
93.
Amuthan Arunkumar Ramabathiran S. Gopalakrishnan 《Journal of Computational and Applied Mathematics》2012
An energy–momentum conserving time integrator coupled with an automatic finite element algorithm is developed to study longitudinal wave propagation in hyperelastic layers. The Murnaghan strain energy function is used to model material nonlinearity and full geometric nonlinearity is considered. An automatic assembly algorithm using algorithmic differentiation is developed within a discrete Hamiltonian framework to directly formulate the finite element matrices without recourse to an explicit derivation of their algebraic form or the governing equations. The algorithm is illustrated with applications to longitudinal wave propagation in a thin hyperelastic layer modeled with a two-mode kinematic model. Solution obtained using a standard nonlinear finite element model with Newmark time stepping is provided for comparison. 相似文献
94.
Solvent effects in the reaction between (anthracen‐9‐yl)methyl sulfides and electron‐deficient acetylenes 下载免费PDF全文
Reshma Gopalakrishnan Jomon P. Jacob Rekha R. Mallia Perupparampil A. Unnikrishnan Sreedharan Prathapan 《Journal of Physical Organic Chemistry》2015,28(7):472-479
Solvent‐dependent diverse reactivity of (anthracen‐9‐yl)methyl sulfides with a few electron‐deficient acetylenes is described. Diversity in reactivity is attributed to competition between one electron transfer, two electron transfer and Diels–Alder reaction of these sulfides with electron‐deficient acetylenes. We have proposed plausible mechanisms to account for various reactions observed by us. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
95.
96.
Jomon P. Jacob Reshma Gopalakrishnan Rekha R. Mallia Jean John Vadakkan Perupparampil A. Unnikrishnan Sreedharan Prathapan 《Journal of Physical Organic Chemistry》2014,27(11):884-891
Herein, we describe diverse reactivity of (anthracen‐9‐yl)methanamines with a few electron‐deficient acetylenes. Depending on the solvent and concentration, (anthracen‐9‐yl)methanamines reacted with acetylenes through one electron transfer, two electron transfer, or Diels–Alder pathways; and under certain conditions, we observed multiple reaction pathways. We have proposed plausible mechanisms to account for various reactions observed by us. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
97.
V. Kanagarajan J. Thanusu M. R. Ezhilarasi M. Gopalakrishnan 《Chemistry of Heterocyclic Compounds》2011,47(1):60-66
A novel approach towards the synthesis of spiropiperidinyl 1,2,4-triazolidine-3-thiones was proposed, exploiting microwave
activation coupled with solvent-free reaction conditions. In search for new leads towards potent antimicrobial agents, we
tested all the synthesized compounds for their in vitro antibacterial activity against Bacillus subtilis and Micrococcus luteus
and antifungal activity against Aspergillus niger, Candida albicans, Candida-6, and Candida-51. Two of the compounds exerted
strong in vitro antibacterial activity against B. subtilis and M. luteus, and all the synthesized compounds were potent against
the tested fungal strains. 相似文献
98.
Michael P. Curtis William H. Bunnelle Thomas G. Pagano Murali Gopalakrishnan 《合成通讯》2013,43(3):321-326
Small heterocyclic amines such as 1,3‐diaza‐bicyclo[3.2.2]nonane are known to be key components of biologically active molecules. A convenient synthesis of this compound utilizing a key Beckmann rearrangement of (Z)‐1‐aza‐bicyclo[2.2.2]octan‐3‐one oxime (6) with conc. H2SO4 under microwave irradiation was achieved. The desired compound (1) was obtained in 20% yield overall. 相似文献
99.
S. Priya R. K. Gopalakrishnan A. Goswami 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):353-359
The commercial Hidex LSC system has been used to measure triple to double coincidence ratio (TDCR), experimental counting efficiency (CE) and the absolute activity for radioactive standards of pure beta emitters viz. 3H, 63Ni and 55Fe, an electron capture nuclide. Colour and chemical quench measurements of 63Ni and 55Fe have been done. An excellent match between TDCR and CE has been obtained for beta emitters, while very large deviations have been observed for 55Fe. The deviation between TDCR and experimental efficiency has been found to be nearly uniform. Based on this, an empirical correction factor for TDCR which gives the correct efficiency has been evaluated, to enable efficient application of this commercial instrument for 55Fe estimation. These TDCR correction factors were further validated by applying for 55Fe activity measurements in ASTM standard steel samples irradiated to a fixed neutron flux in research reactor CIRUS. Finally, 55Fe activity in steel sample from APSARA reactor decommissioning waste was successfully estimated using this modified TDCR. 相似文献
100.
Reshma V. R. Nair Devi Velayudhan Jayasree Prabath Gopalakrishnan Biju 《Natural product research》2020,34(16):2319-2322
Abstract Humboldtia unijuga Bedd., endemic to Agasthyamala in Western Ghats in India, is traditionally used by local Kani tribes for chicken pox, head ache and snake bite. This study reports the isolation of erythrodiol-3-acetate (HU-1) and 2,4-di-tert-butylphenol (HU-2) from H. unijuga roots and their anti-inflammatory and anticancer activities in macrophage, skin and breast cancer cell lines. Effects of HU-1 and HU-2 treatments (50, 100?µg/mL) on gene expression profiles of pro-inflammatory cytokines TNFα, IL-6 and IL-1β, and apoptosis genes p53 and caspase 7 were studied. HU-2 exerted a significantly superior anti-inflammatory effect compared to HU-1 in all three pro-inflammatory genes. HU-2 showed a superior dose dependent anticancer effect through activation of p53 gene over HU-1 in MCF-7 cells. HU-1 exhibited a dose dependent effect on caspase 7 gene in both cell lines while HU-2 was more effective in A431. HU-2 has potential for development as a novel anti-inflammatory and anticancer agent. 相似文献