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141.
SL Jothy A Torey I Darah YS Choong D Saravanan Y Chen LY Latha S Deivanai S Sasidharan 《Molecules (Basel, Switzerland)》2012,17(9):10292-10305
The genus Cassia, comprising about 600 species widely distributed worldwide is well known for its diverse biological and pharmacological properties. Cassia spectabilis (sin Senna spectabilis) (DC) Irwin et Barn (Fabaceae) is widely grown as an ornamental plant in tropical and subtropical areas. C. spectabilis has been commonly used in traditional medicine for many years. Information in the biomedical literature has indicated the presence of a variety of medicinally-important chemical constituents in C. spectabilis. Pharmacological studies by various groups of investigators have shown that C. spectabilis possesses significant biological activity, such as antibacterial, antibiofilm, antifungal and antioxidant properties. Beside this, toxicity studies of this plant have revealed no toxic effect on mice. In view of the immense medicinal importance of C. spectabilis, this review aimed at compiling all currently available information on C. spectabilis's botany, phytochemistry, pharmacology, and mechanism of actions, toxicology and its ethnomedicinal uses. 相似文献
142.
P. Saravanan S.V. KamatB. Sreedhar 《Journal of magnetism and magnetic materials》2012,324(6):1201-1204
In this study, we investigated the microstructure, phase evolution and magnetic properties of nanogranular films of Sm-Co compounds processed by the sol-gel method. By controlling the compositional ratio of Sm:Co precursor concentration, nanogranular films consisting of three distinct hard magnetic phases namely, Sm2Co7, SmCo5 and Sm2Co17 with coercivity values of 1.78, 2.94 and 2.12 kOe, respectively, were obtained through this technique. 相似文献
143.
K. Balamurugan R. Saravanan K. Asharamani P. Manimaran S. Mariyappan N. Srinivasan Y. Ono M. Isshiki T. Kajitani 《Journal of Crystal Growth》2003,250(3-4):382-392
Using a perfect single crystal sample of CdTe grown using PVT method, the electronic charge transfer in the II–VI compound semiconductor CdTe at 200 and 300 K has been evaluated using two different approaches: (1) by solving a quadratic equation involving the observed structure factors of h+k+l=4n+2 type reflections; and (2) by a graphical approach in which the observed and calculated atomic form factors are extrapolated to sinθ/λ=0, to determine the transferred charge. Precise X-ray structure factors collected using MoK radiation have been used for the analysis. The results obtained are reasonable and clearly indicate the ionicity by which charge is transferred from Cd to Te in CdTe. 相似文献
144.
Jielin Zhang Eleonora Grandi Haigen Fu Dr. Thangavelu Saravanan Laura Bothof Pieter G. Tepper Dr. Andy-Mark W. H. Thunnissen Prof. Dr. Gerrit J. Poelarends 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(1):437-443
Aspartic acid derivatives with branched N-alkyl or N-arylalkyl substituents are valuable precursors to artificial dipeptide sweeteners such as neotame and advantame. The development of a biocatalyst to synthesize these compounds in a single asymmetric step is an as yet unmet challenge. Reported here is an enantioselective biocatalytic synthesis of various difficult N-substituted aspartic acids, including N-(3,3-dimethylbutyl)-l -aspartic acid and N-[3-(3-hydroxy-4-methoxyphenyl)propyl]-l -aspartic acid, precursors to neotame and advantame, respectively, using an engineered variant of ethylenediamine-N,N′-disuccinic acid (EDDS) lyase from Chelativorans sp. BNC1. This engineered C–N lyase (mutant D290M/Y320M) displayed a remarkable 1140-fold increase in activity for the selective hydroamination of fumarate compared to that of the wild-type enzyme. These results present new opportunities to develop practical multienzymatic processes for the more sustainable and step-economic synthesis of an important class of food additives. 相似文献
145.
Yan Li Dr. Kartik Chandra Mondal Dr. Prinson P. Samuel Prof. Dr. Hongping Zhu Claudia M. Orben Dr. Saravanan Panneerselvam Priv.‐Doz. Dr. Birger Dittrich Dr. Brigitte Schwederski Prof. Dr. Wolfgang Kaim Totan Mondal Dr. Debasis Koley Prof. Dr. Herbert W. Roesky 《Angewandte Chemie (International ed. in English)》2014,53(16):4168-4172
A neutral C4 cumulene 1 that includes a cyclic alkyl(amino) carbene (cAAC), its air‐stable radical cation 1 .+, and dication 1 2+ have been synthesized. The redox property of 1 .+ was studied by cyclic voltammetry. EPR and theoretical calculations show that the unpaired electron in 1 .+ is mainly delocalized over the central C4 backbone. The commercially available CBr4 is utilized as a source of dicarbon in the cumulene synthesis. 相似文献
146.
Sivaperuman Saravanan Santhanagopalan Purushothaman Irudayaraj Bernadette Amali 《合成通讯》2013,43(16):2882-2888
The chemoselective reactions of selenium dioxide with differently substituted adducts generated by 1,4-addition on benzylidene acetophenone are described. This reaction has been shown to be dependent on the nature of the substituent present, leading to different products by α-oxidation/α-oxidation followed by dehydrogenation/dehydrogenation, enolization, and cyclization. 相似文献
147.
Guangcai Xu Dr. Michele Crotti Dr. Thangavelu Saravanan Kim M. Kataja Prof. Dr. Gerrit J. Poelarends 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(26):10460-10464
Peroxygenases are heme-dependent enzymes that use peroxide-borne oxygen to catalyze a wide range of oxyfunctionalization reactions. Herein, we report the engineering of an unusual cofactor-independent peroxygenase based on a promiscuous tautomerase that accepts different hydroperoxides (t-BuOOH and H2O2) to accomplish enantiocomplementary epoxidations of various α,β-unsaturated aldehydes (citral and substituted cinnamaldehydes), providing access to both enantiomers of the corresponding α,β-epoxy-aldehydes. High conversions (up to 98 %), high enantioselectivity (up to 98 % ee), and good product yields (50–80 %) were achieved. The reactions likely proceed via a reactive enzyme-bound iminium ion intermediate, allowing tweaking of the enzyme's activity and selectivity by protein engineering. Our results underscore the potential of catalytic promiscuity for the engineering of new cofactor-independent oxidative enzymes. 相似文献
148.
149.
Microfluidics for food, agriculture and biosystems industries 总被引:1,自引:0,他引:1
Microfluidics, a rapidly emerging enabling technology has the potential to revolutionize food, agriculture and biosystems industries. Examples of potential applications of microfluidics in food industry include nano-particle encapsulation of fish oil, monitoring pathogens and toxins in food and water supplies, micro-nano-filtration for improving food quality, detection of antibiotics in dairy food products, and generation of novel food structures. In addition, microfluidics enables applications in agriculture and animal sciences such as nutrients monitoring and plant cells sorting for improving crop quality and production, effective delivery of biopesticides, simplified in vitro fertilization for animal breeding, animal health monitoring, vaccination and therapeutics. Lastly, microfluidics provides new approaches for bioenergy research. This paper synthesizes information of selected microfluidics-based applications for food, agriculture and biosystems industries. 相似文献
150.
Synthesis and Photophysics of Some Novel Imidazole Derivatives Used as Sensitive Fluorescent Chemisensors 总被引:1,自引:0,他引:1
Kanagarathinam Saravanan Natesan Srinivasan Venugopal Thanikachalam Jayaraman Jayabharathi 《Journal of fluorescence》2011,21(1):65-80
Some novel imidazole derivatives were developed for highly sensitive chemisensors for transition metal ions. Since these compounds are sensitive to different external stimulations such as UV irradiation, heat, increasing pressure and changing the environmental pH causing colour change and so they can be used as a ??multi-way?? optically switchable material. A prominent fluorescence enhancement was found in the presence of transition metal ions such as Hg2+, Pb2+ and Cu2+ and this was suggested to result from the suppression of radiationless transitions from the n-??* state in the chemisensors. The existence of C-H??.O intramolecular hydrogen bonding in dmphnpi is confirmed by the Natural Bond Orbital analysis (NBO). The Mulliken, NBO charge analysis and the HOMO-LUMO energies were also calculated. The electric dipole moment (??) and the first-hyperpolarisability (??) value of the investigated molecules have been studied both experimentally and theoretically which reveal that the synthesized molecules have microscopic non-linear optical (NLO) behaviour with non-zero values. Ground and excited state DFT calculation were carried out in order to find out dipole moment and energy. 相似文献