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81.
Majeti BK Singh RS Yadav SK Bathula SR Ramakrishna S Diwan PV Madhavendra SS Chaudhuri A 《Chemistry & biology》2004,11(4):427-437
Herein, we report enhanced intravenous mouse lung transfection using novel cyclic-head-group analogs of usually open-head cationic transfection lipids. Design and synthesis of the new cyclic-head lipid N,N-di-n-tetradecyl-3,4-dihydroxy-pyrrolidinium chloride (lipid 1) and its higher alkyl-chain analogs (lipids 2-4) and relative in vitro and in vivo gene transfer efficacies of cyclic-head lipids 1-4 to their corresponding open-head analogs [lipid 5, namely N,N-di-n-tetradecyl-N,N-(2-hydroxyethyl)ammonium chloride and its higher alkyl-chain analogs, lipids 6-8] have been described. In stark contrast to comparable in vitro transfection efficacies of both the cyclic- and open-head lipids, lipids 1-4 with cyclic heads were found to be significantly more efficient (by 5- to 11-fold) in transfecting mouse lung than their corresponding open-head analogs (5-8) upon intravenous administration. The cyclic-head lipid 3 with di-stearyl hydrophobic tail was found to be the most promising for future applications. 相似文献
82.
RK Yadav JO Baeg GH Oh NJ Park KJ Kong J Kim DW Hwang SK Biswas 《Journal of the American Chemical Society》2012,134(28):11455-11461
The photocatalyst-enzyme coupled system for artificial photosynthesis process is one of the most promising methods of solar energy conversion for the synthesis of organic chemicals or fuel. Here we report the synthesis of a novel graphene-based visible light active photocatalyst which covalently bonded the chromophore, such as multianthraquinone substituted porphyrin with the chemically converted graphene as a photocatalyst of the artificial photosynthesis system for an efficient photosynthetic production of formic acid from CO(2). The results not only show a benchmark example of the graphene-based material used as a photocatalyst in general artificial photosynthesis but also the benchmark example of the selective production system of solar chemicals/solar fuel directly from CO(2). 相似文献
83.
Singh AK Chawla R Rai A Yadav LD 《Chemical communications (Cambridge, England)》2012,48(31):3766-3768
NHC-catalysed azalactone ring-opening and piperidine ring-closing cascade with α,β-unsaturated aldehydes (enals) in a one-pot operation is reported. The present reaction cascade offers a convenient method for a highly diastereoselective synthesis of multifunctionalised piperidines in excellent yields under mild conditions. 相似文献
84.
Cerium(III) chloride heptahydrate (CeCl3·7H2O) catalyzes the reaction of substituted salicylaldehydes with 1,3-cyclohexane dione or dimedone in aqueous medium at reflux temperature to afford the corresponding 1-oxo-1,2,3,4,9,10-hexahydroxanthene derivatives4 0 in high yields. 相似文献
85.
Efficient syntheses of pheromone components of Aproaerema modicella starting from a common intermediate 7-octyn-1-ol is described. 相似文献
86.
Yadav Krishna K. Guchhait Sujit Kumar Sunaina Ankush Hussain C. M. Ganguli Ashok K. Jha Menaka 《Journal of Solid State Electrochemistry》2019,23(12):3243-3253
Journal of Solid State Electrochemistry - Surface degradation of steel is one of the key problems of steel end user because of the electrochemical reaction at the steel surface caused by... 相似文献
87.
Carl Henrik Grbitz Vitthal N. Yadav 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(8):888-891
The title dipeptide {systematic name: (S)‐2‐[(S)‐2‐azaniumylbutanamido]‐3‐hydroxypropanoate}, C7H14N2O4, was synthesized in the anticipation that it would form nanoporous crystals with hexagonal symmetry. Single‐crystal X‐ray diffraction analysis showed that it had instead adopted a unit cell in the space group I4, similar to L‐alanyl‐L‐alanine [Fletterick, Tsai & Hughes (1970). J. Phys. Chem. 75 , 918–922]. The resulting packing arrangement has a high density for a peptide (1.462 Mg m−3), which is rendered possible by extensive disorder over two positions for the ethyl side chain of the 2‐aminobutyric acid fragment and over three positions for the serine side chain.<!?tpb=17.5pt> 相似文献
88.
Mayer's definition of bond order and valence number of an atom in a molecule in the ab initio SCF theory have been applied to calculate bond orders and valence numbers using different ab initio methods for some fluorobenzenes. The results have been discussed in the light of Mulliken population analysis. The traditional view that the valency of an atom is directly related to the atomic charge is found to be invalid in the present ab initio calculations. 相似文献
89.
Asymmetric total synthesis of the sex pheromones of Japanese beetle and currant stem girdler, (R)‐japonilure (1) and (4R,9Z)‐9‐octadecen‐4‐olide (2), has been achieved. 相似文献
90.
Atul C. Chaskar Arun A. Yadav Bhushan P. Langi Anita Murugappan Chetan Shah 《合成通讯》2013,43(19):2850-2856
Simple, efficient, and mild method for α-thiocyanation of ketones in presence of heteropolyacid has been developed. This methodology offered α-oxothiocyanates in good to excellent yields at room temperature in a highly selective manner. The catalyst could be efficiently recovered from the reaction and reused. 相似文献