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941.
942.
943.
Wenbo Ma Prof. Dr. Lutz Ackermann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(41):13925-13928
Cationic ruthenium(II) complexes enabled oxidative alkenylations of phenols bearing easily cleavable directing groups. The optimized catalytic system allowed twofold C? H bond activations with excellent chemo‐, site‐, and diastereoselectivities. The double C? H functionalization process proceeded efficiently in an aerobic fashion under an atmosphere of ambient air. Detailed mechanistic studies were performed and provided strong support for an initial reversible C? H bond activation by the formation of six‐membered ruthenacycles as the key intermediates. 相似文献
944.
945.
Jinfeng Qu Li Ma Junhua Zhang Steffen Jockusch Ilyas Washington 《Photochemistry and photobiology》2013,89(2):310-313
Ubiquinol is a plasma antioxidant. The mechanisms responsible for maintenance of plasma ubiquinol are poorly understood. Here, we show that metabolites of chlorophyll can be found in blood plasma of animals that are given a chlorophyll‐rich diet. We also show that these metabolites catalyze the reduction of plasma ubiquinone to ubiquinol in the presence of ambient light, in vitro. We propose that dietary chlorophyll or its metabolites, together with light exposure, regulate plasma redox status through maintaining the ubiquinol pool. 相似文献
946.
Phthalimide derivatives as nitrogen nucleophiles with α,β‐unsaturated aldehydes for asymmetric aza‐Michael additions have been reported. The reactions proceed smoothly to afford corresponding Michael adducts in good yields (up to 98%) and enantioselectivities (up to 95% ee). 相似文献
947.
T. Kupka J. G. Małecki P. Lodowski M. Jaworska J. O. Dzięgielewski 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):505-506
Abstract NMR, IR and semi empirical Molecular Orbital PM3 studies on selected β-lactam antibiotics are reported. The role of sulfur in β-lactam antibiotics is discussed. 相似文献
948.
Łukasz Janczewski Małgorzata Walczak Justyna Frączyk Zbigniew J. Kamiński 《合成通讯》2013,43(23):3290-3300
The microwave-assisted Cannizzaro reaction was studied in order to develop fully reproducible synthetic protocols for transformation of aldehydes to carboxylic acid and alcohols. Optimised were the following process parameters: power, temperature, and time. Aromatic, heteroaromatic and aliphatic aldehydes were used in the studies. It was found that furfural, thiophene-2-carbaldehyde, pyridinecarboxaldehyde and aromatic aldehydes react under mild conditions, while 1-methyl-pyrrole-2-carboxaldehyde derivatives and aliphatic aldehydes require more drastic reaction conditions and a longer exposure time to microwave radiation. 相似文献
949.
The palladium-catalyzed reaction of acetylenic selenides with tributyltin hydride give verstile (E)-α-selanyl vinylstannanes regio-and stereoselectively. By iododestannylation, stereodefined(E)-α-iodo-selanyl alkenes have been synthesized. 相似文献
950.
Ferenc Sóti Mária Incze Zsuzsanna Kardos-Balogh Maária Kajtár-Peredy Csaba Szántay 《合成通讯》2013,43(12):1689-1698
7-Methoxytryptamine (6a) was prepared from cheap and easily available starting materials by using the Abramovitch-Shapiro method. 相似文献