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991.
Biavardi E Battistini G Montalti M Yebeutchou RM Prodi L Dalcanale E 《Chemical communications (Cambridge, England)》2008,(14):1638-1640
We report here the monitoring of reversible guest inclusion in phosphonate cavitands through a large increase in luminescence intensity caused by the modulation of the exoergonicity of an electron-transfer reaction. 相似文献
992.
Main M Snaith JS Meloni MM Jauregui M Sykes D Faulkner S Kenwright AM 《Chemical communications (Cambridge, England)》2008,(41):5212-5214
The Ugi reaction offers an effective method for preparing chromophore-appended DOTA-monoamide ligands, which can readily be elaborated to their lanthanide complexes. 相似文献
993.
Enantiopure chiral amidic derivatives of sinapic acid were oxidised with hydrogen peroxide using horseradish peroxidase (HRP) as the catalyst to give the aryltetraline dilignol thomasidioic acid. Trans-diastereoselectivity and enantioselectivity in the formation of thomasidioic acid was observed. Computational methods show that the enantioselectivity is controlled by the beta-beta oxidative coupling step, while the diastereoselectivity is controlled by the stability of the reactive conformation of the intermediate quinomethide. 相似文献
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Investigating Alanine–Silica Interaction by Means of First‐Principles Molecular‐Dynamics Simulations
In our attempts to achieve a detailed understanding of protein–silica interactions at an atomic level we have, as a first step, simulated a small system consisting of one alanine in different protonation states, and a hydroxylated silica surface, using a first‐principles molecular‐dynamics technique. The simulations are carried out in vacuo as well as in the presence of water molecules. In the case of a negatively charged surface and an alanine cation, an indirect proton transfer from the alanine carboxylic group to the surface takes place. The transfer involves several water molecules revealing an alanine in its zwitterionic state interacting with the neutral surface through indirect hydrogen bonds mediated by water molecules. During the simulation of the zwitterionic state the ammonium group eventually establishes a direct ? N? H???O? Si interaction, suggesting that the surface–amino group interaction is stronger than the interaction between the surface and the carboxylic group. In vacuum simulations, the amino group exhibits clearly stronger interactions with the surface than the carboxylic group. 相似文献