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991.
Fanbo SongJing Zhang Quanbin CuiTing Wang Wenbin ChenLuyuan Li Zhen Xi 《Tetrahedron letters》2012,53(9):1102-1104
Inositol phosphates regulate important biological functions in intracellular signal transduction events. Phosphonates, because of the stability towards the action of phosphatases, were extensively used to replace phosphates. We herein reported the synthesis of inositol phosphonate analogues using myo-inositol as the starting material, and found that two of phosphonate analogues exhibited relative good cytotoxic activity against non-small cell lung cancer (NSCLC) cell line A549. 相似文献
992.
A general, efficient, and more practical protocol for the base-mediated intermolecular or intramolecular S-arylation leading to the 2-aminobenzothiazole derivatives is reported. Remarkably, all reactions were carried out under transition-metal-free conditions with good to excellent yields, rendering the methodology presented herein highly valuable from both environmental and economic points of view. 相似文献
993.
Yi-Si Feng Hong-Xia Qi Wei-Cheng Wang Yu-Feng Liang Hua-Jian Xu 《Tetrahedron letters》2012,53(23):2914-2917
A novel synthetic protocol for 2-aminophenyl sulfide derivatives via the reactions of benzothiazole with aryl iodides was reported for the first time. The reactions were catalyzed by CuCl with tetrabutylammonium hydroxide as the base and water as the solvent without ligand at 50 °C or room temperature. A variety of aryl iodides underwent the C–S cross-coupling reaction with benzothiazole to afford smoothly the corresponding products in excellent yield. 相似文献
994.
Polystyrene-bound diethanolamine based ionic liquids (PS-DHEEAB and PS-THEAB) were synthesized and applied for the chemical fixation of CO2 into cyclic carbonates without any additional co-catalyst and solvent. The effect of the catalysts with different number of hydroxyl group in the cation of the IL on the reaction was systematically investigated. Highest activity and selectivity were achieved in the presence of polystyrene supported diethanolamine ethyl bromide (PS-DHEEAB) in comparison with other catalysts employed. The catalyst was tough in stability and also found to be extended to a variety of terminal epoxides and aziridines. The relationship between high catalytic reactivity and the –OH functional groups was proposed. 相似文献
995.
De-Yang Zhang Chang-Bin Yu Min-Can Wang Kai Gao Yong-Gui Zhou 《Tetrahedron letters》2012,53(20):2556-2559
A new electronically deficient atropisomeric diphosphine ligand (S)-CF3O-BiPhep was synthesized from 1-bromo-3-(trifluoromethoxy)benzene in high yield. The key steps included oxidative coupling with anhydrous ferric chloride and optical resolution by (+)-DMTA. The ligand afforded high performance for Ir-catalyzed asymmetric hydrogenation of quinolines with ee up to 92% and TON up to 25,000. It was also successfully applied to the Pd-catalyzed asymmetric hydrogenation of simple indoles with ee up to 87% and Rh-catalyzed asymmetric 1,4-addition of phenylboronic acid to 2-cyclohexenone with 97% ee. 相似文献
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1000.
A bicyclo[2.2.2]octane C/D ring system,with a lactonic ring at C-8 and C-9,of the atisine-type C20-diterpenoid alkaloids,was successfully synthesized,using an oxidative dearomatization/intramolecular Diels-Alder reaction. 相似文献