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991.
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Víctor Yañez Rodríguez Miguel Ángel del Águila María José Iglesias Fernando López Ortiz 《Tetrahedron》2012,68(36):7355-7362
Directed ortho lithiation of diphenylphosphinic acid and subsequent electrophilic trapping provides mono ortho-functionalized derivatives including enantiopure γ-aminophosphinic acids in moderate yields. Copper catalyzed coupling of the ortho anion leads to biphenyl-2,2′-diylbis(phenylphosphinic acid), a phosphorus analogue of biphenyl-2,2′-dicarboxylic acid. Preliminary studies of the metal-binding abilities of this O,O-chelating ligand towards a series of metal cations are included. 相似文献
995.
This work reports the theoretical study of the aromaticity of a series of carbocycles (benzene, cyclohexane, bent and planar cyclooctatetraene) and heterocycles (pyridine, furan, thiophene, pyrrole) and their didehydro forms (arynes and hetarynes). As aromaticity probe Schleyer's NICS were used and represented in two 3D isosurfaces of the electron density. The spatial 3D representation of the NICS is shown to be a powerful tool to visualize the aromaticity (or its absence) of different molecules. 相似文献
996.
We studied effect of 1-aminoanthracene (1-AMA) binding on the structures of dimeric β lactoglobulin, dimeric odorant binding
protein (OBP) and monomeric α1-acid glycoprotein (lipocalin family proteins) by monitoring fluorescence excitation spectra and measuring fluorescence lifetimes
of the tryptophan residues of the proteins. Results show that binding of 1-AMA to β lactoglobulin and OBP modifies their conformation
even at low probe concentration compared to that of the proteins. Structural modification induces a red shift of the fluorescence
excitation spectra maximum of tryptophan residues accompanied with an increase of the third fluorescence lifetime and a decrease
of its pre-exponential factor. These effects were not observed for α1-acid glycoprotein, probably as the result of carbohydrate presence. These data raise doubts concerning use of 1-AMA as a
probe to study biological properties of β lactoglobulin and OBP. 相似文献
997.
A simple and rapid method for the preparation of a series of novel quinoxaline derivatives in the presence of Ag+ is reported. 相似文献
998.
Dr. Aloysius Siriwardena Kiran Kumar Pulukuri Pancham S. Kandiyal Dr. Saumya Roy Dr. Omprakash Bande Dr. Subhash Ghosh Dr. José Manuel Garcia Fernández Dr. Fernando Ariel Martin Dr. Jean‐Marc Ghigo Dr. Christophe Beloin Dr. Keigo Ito Dr. Robert J. Woods Dr. Ravi Sankar Ampapathi Dr. Tushar Kanti Chakraborty 《Angewandte Chemie (International ed. in English)》2013,52(39):10221-10226
999.
René Roy Craig A. Laferrière Apdrzej Gamian Harold J. Jennings 《Journal of carbohydrate chemistry》2013,32(1):161-165
Abstract A simplified procedure for the synthesis of acetochloroneuraminic acid is described starting from the methyl ester. N-acetyl neuraminic acid α-allyl glycoside was prepared in high yield using silver salicylate as catalyst. Reductive ozonolysis of the allyl group, followed by direct reductive ami nation to protein carriers, gave immunogenic neoglycoproteins. Copolymerization of the α-allyl glycoside with acrylamide produced a water-soluble pseudopolysaccharide useful for the EL ISA technique. 相似文献