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Dalvit C Flocco M Knapp S Mostardini M Perego R Stockman BJ Veronesi M Varasi M 《Journal of the American Chemical Society》2002,124(26):7702-7709
The Achilles heel of ligand-based NMR screening methods is their failure to detect high-affinity ligands and molecules that bind covalently to the receptor. We have developed a novel approach for performing high-throughput screening with NMR spectroscopy that overcomes this limitation. The method also permits detection of potential high-affinity molecules that are only marginally soluble, thus significantly enlarging the diversity of compounds amenable to NMR screening. The techniques developed utilize transverse and/or selective longitudinal relaxation parameters in combination with competition binding experiments. Mathematical expressions are derived for proper setup of the NMR experiments and for extracting an approximate value of the binding constant for the identified ligand from a single-point measurement. With this approach it is possible to screen thousands of compounds in a short period of time against protein or DNA and RNA fragments. The methodology can also be applied for screening plant and fungi extracts. 相似文献
25.
Anastasia Rusina Maxim Durach Mark I. Stockman 《Applied Physics A: Materials Science & Processing》2010,100(2):375-378
In this Letter we develop a theory of spoof plasmons propagating on real metals perforated with planar periodic grooves. Deviation
from the spoof plasmons on perfect conductor due to finite skin depth has been analytically described. This allowed us to
investigate important propagation characteristics of spoof plasmons such as quality factor and propagation length as the function
of the geometrical parameters of the structure. We have also considered THz field confinement by adiabatic increase of the
depth of the grooves. It is shown that the finite skin depth limits the propagation length of spoof plasmons as well as a
possibility to localize THz field. Geometrical parameters of the structure are found which provide optimal guiding and localization
of THz energy. 相似文献
26.
Two-directional total stereoselective syntheses of (+/-)-hippodamine and (+/-)-epi-hippodamine, utilising a tandem deprotection/intramolecular double Michael addition sequence as the key step, are presented. 相似文献
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[reaction: see text] The preparation of a range of alkyl and aryl chiral vinyl aziridines was achieved in high yield and stereoselectivity, and with excellent diastereoselectivity, by reaction of tert-butylsulfinylimines with the ylide derived from S-allyl tetrahydrothiophenium bromide. 相似文献
28.
Self-similar chain of metal nanospheres as an efficient nanolens 总被引:1,自引:0,他引:1
As an efficient nanolens, we propose a self-similar linear chain of several metal nanospheres with progressively decreasing sizes and separations. To describe such systems, we develop the multipole spectral expansion method. Optically excited, such a nanolens develops the nanofocus ("hottest spot") in the gap between the smallest nanospheres, where the local fields are enhanced by orders of magnitude due to the multiplicative, cascade effect of its geometry and high Q factor of the surface plasmon resonance. The spectral maximum of the enhancement is in the near-ultraviolet region, shifting toward the red region as the separation between the spheres decreases. The proposed system can be used for nanooptical detection, Raman characterization, nonlinear spectroscopy, nanomanipulation of single molecules or nanoparticles, and other applications. 相似文献
29.
A direct multi-component coupling of (2S,4R,5S)-N-tosyl-4-methyl-5-phenyl-1,2,3-oxathiozolidine-2-oxide with mesityl magnesium bromide, LHMDS and a range of aldehydes produces chiral sulfinimines in essentially optically pure form in an operationally simple single pot procedure. 相似文献
30.
This article brings together for the first time reviews of all the synthetic attempts towards the spirocyclic histrionicotoxin alkaloids published since the discovery of the group in 1971. This covers 5 total syntheses of the fully unsaturated parent alkaloid HTX-283A, 7 total syntheses of perhydrohistrionicotoxin, 15 total syntheses of other members of this alkaloid family, 25 formal syntheses, and 19 partial syntheses involving the successful formation of the core azaspirocyclic structure but lacking advancement towards the target structure. 相似文献