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101.
102.
Ourida Saidi A. John Blacker Stephen P. Marsden Robert J. Watson 《Tetrahedron letters》2010,51(44):5804-5806
Amines have been formylated using aqueous formaldehyde or paraformaldehyde and the iridium catalyst [Cp∗IrI2]2. Paraformaldehyde acts as both a formylating agent and an oxidant. 相似文献
103.
Aminolysis of a variety of epoxides by aliphatic and aromatic amines in water, in the absence of any catalyst with high yields, is reported. Beta-amino alcohols were formed under mild conditions with high selectivity and in excellent yields. [reaction: see text] 相似文献
104.
The solid LiClO4-mediated one-pot reaction of aldehydes with secondary amines and C nucleophiles afforded the corresponding aminoalkylation products in high yields. Unlike the previous reported procedure, the aminoalkylation of aldehyde was achieved in the presence of only 0.5 equivalents of solid lithium perchlorate in dichloromethane as the solvent with good to high yields at room temperature. 相似文献
105.
James D. Grayson Matthew P. Baumgartner Cleide Dos Santos Souza Samuel J. Dawes Imane Ghafir El Idrissi Jennifer C. Louth Sasha Stimpson Emma Mead Charlotte Dunbar Joanna Wolak Gary Sharman David Evans Anastasia Zhuravleva Margarita Segovia Roldan Nicola Antonio Colabufo Ke Ning Claire Garwood James A. Thomas Benjamin M. Partridge Antonio de la Vega de Leon Valerie J. Gillet Amlia P. Rauter Beining Chen 《Chemical science》2021,12(10):3768
Amyloid β oligomers (Aβo) are the main toxic species in Alzheimer''s disease, which have been targeted for single drug treatment with very little success. In this work we report a new approach for identifying functional Aβo binding compounds. A tailored library of 971 fluorine containing compounds was selected by a computational method, developed to generate molecular diversity. These compounds were screened for Aβo binding by a combined 19F and STD NMR technique. Six hits were evaluated in three parallel biochemical and functional assays. Two compounds disrupted Aβo binding to its receptor PrPC in HEK293 cells. They reduced the pFyn levels triggered by Aβo treatment in neuroprogenitor cells derived from human induced pluripotent stem cells (hiPSC). Inhibitory effects on pTau production in cortical neurons derived from hiPSC were also observed. These drug-like compounds connect three of the pillars in Alzheimer''s disease pathology, i.e. prion, Aβ and Tau, affecting three different pathways through specific binding to Aβo and are, indeed, promising candidates for further development.A new approach combining virtual screening, 19F and STD NMR, and biochemical assays using hiPSC and targetting multiple pathways involving Aβ, PrPC and Tau provides a more effective strategy for Alzheimer''s disease drug discovery than Aβ only approach. 相似文献
106.
Fouzia Gudira Malika Saidi Idrissi Harald Krautscheid Lahcen El Ammari 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):m530-m532
In the title compound, μ‐3,4′‐bi‐1,2,4‐triazole‐di‐μ‐chloro‐copper(II) monohydrate, {[CuCl2(C4H4N6)]·H2O}n, the Cu atom is located in a distorted octahedron consisting of two N atoms and four Cl atoms. The structural unit is an infinite chain in which octahedral groups, connected by shared edges, are also linked by bitriazole molecules. The bitriazole ligand, the Cu atom and the water O atom all lie on independent twofold axes. The structure is held together by hydrogen bonds between the water molecules and the non‐coordinated N atoms of the ligand, and by van der Waals forces. 相似文献
107.
108.
Allen A. D. Rangwala H. Saidi K. Tidwell Th. T. Wang J. 《Russian Chemical Bulletin》2001,50(11):2130-2133
1,2- and 1,3-Bis(ketenyl)benzenes formed by double dehydrochlorination and by double Wolff rearrangement, respectively, gave ketenyl IR absorption at 2115, and 2122, and 2116 cm–1, respectively. Reaction of these bisketenes with the aminoxyl radical tetramethylpiperidin-1-yloxyl (TEMPO) gave the corresponding tetraadducts as mixtures of meso- and d,l-isomers. The kinetics of the reaction of 1,3-bis(ketenyl)benzene with TEMPO gave a rate constant comparable to that of the monoketene PhCH=C=O. The reactions proceed by the initial attack of TEMPO on the carbonyl carbon of one ketenyl group followed by fast capture of the intermediate radical by a second TEMPO, and then reaction of the remaining ketene. 相似文献
109.
An environmentally benign and efficient process for the preparation of β-hydroxysulfides was developed by a practical and simple reaction of thiols with epoxides in water catalyzed by K2CO3 in high yields and short reaction times. 相似文献
110.
This study aims to investigate numerically the laminar flow and heat transfer in a pseudoplastic non-Newtonian falling liquid
film on a horizontal cylinder for the constant heat flux and isothermal boundary conditions. The inertia terms are taken into
account. An implicit finite difference method is carried out to solve the governing boundary layer equations. The effects
of operational parameters on the hydrodynamic and heat transfer characteristics are examined and discussed in detail. The
results presented show that the local and average Nusselt numbers varies significantly as a function of the concentration
of aqueous carboxymethylcellulose (CMC) solutions and the cylinder diameter. Higher concentration of aqueous CMC solutions
generate larger heat transfer coefficients. Finally, a comparison with the experimental and numerical results available in
the literature for Newtonian fluids shows clearly that the present analysis is reasonably accurate.
Received on 29 March 2001 / Published online: 29 November 2001 相似文献