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1.
5‐Amino‐4‐methyl‐2‐phenyl‐6‐substitutedfuro[2,3‐d]pyrimidines ( 2a‐c ) were reacted with 2,5‐dimethoxytetrahydrfuran to afford the pyrrolyl derivatives 3a‐c . Compound 3a was chosen as intermediate for the synthesis of poly fused heterocycles incorporated furopyrimidines moiety 4–11 . Some of the synthesized compounds were screened for their antibacterial and antifungal activities. 相似文献
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[reaction: see text]. Unified and highly convergent total syntheses of (+)-macrosphelides A and B are described. Key features of the syntheses include (1) concise synthesis of the optically active delta-hydroxy-gamma-keto alpha,beta-unsaturated acid fragment via the direct addition of a trans-vinylogous ester anion equivalent to the readily available Weinreb amide and (2) facile construction of the 16-membered macrolide core of the macrosphelide series via an intramolecular nitrile-oxide cycloaddition (INOC). 相似文献
4.
An unusually stable molecular capsule was formed by heating phenyleneurea-spanned resorcinarene cavitand with 4-methyl-N-p-tolylbenzamide. The molecular capsule behaved as a discrete molecular entity showing a cylindrical D(4d) structure and showed no guest exchange in toluene-d(8) even at 100 degrees C. [structure: see text] 相似文献
5.
Braverman Michael SH.; Stepanov Vladimir D. 《Bulletin London Mathematical Society》1994,26(3):283-287
Necessary and sufficient conditions for the boundedness of thediscrete Hardy operator of the form , from to when 0 < q < 1 <p , is given. 相似文献
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Aromatic molecular "clips" bearing two symmetrically bound platinum moieties have been prepared. The molecular "clip" 4 readily self-assembled with linear linkers such as 4,4'-bipyridyl, 1,4-bis[2-(4-isocyano-3,5-diisopropylphenyl)ethynyl]benzene, and nicotinic acid to form molecular rectangles. The overall dimensions of the rectangle 7 were 7.3 Angstroms x 15.3 Angstroms. The molecular "clip" also self-assembled with tritopic pyridyl and isocyanide ligands to form trigonal prismatic frameworks. The characterization of the supramolecules by multinuclear NMR, electrospray mass spectrometry, and X-ray crystal structures is also reported. 相似文献
8.
Primary emphasis is placed on the effects of coating parameters such as coating thickness and tip size, the coating thickness variations due to different draw speeds, and induced maximum shear rate in the applicator. However, in this analysis the flow region is divided into two because of the mixed boundary conditions: non-slip condition (region I) and free shear condition along the meniscus (region II). The surface tension at the edge in region II is balanced with the pressure difference, which becomes a constraint for the flow rate. 相似文献
9.
Gha-Young Kim Tack-Jin Kim Si-Hyung Kim Seungwoo Paek 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(3):1261-1265
The employment of multiple electrode pairs is one of the ways to achieve a high-throughput electrowinner. In order to improve the U/TRU recovery rate and also to obtain economic advantages for a molten salt electrowinning process, which is a major step in pyroprocessing, the development of an electrode module having a compact structure is required. Here, we designed an anode-liquid cathode module (ALCM), where two graphite anodes are symmetrically arranged centering on a liquid Cd cathode with a mesh stirrer to prevent the growth of U dendrites, to be applied to the electrowinning process. As a preliminary study, basic electrochemical characterization of the designed electrode module was conducted and its capability for U recovery was evaluated in the ALCM-employed lab-scale electrowinner including LiCl–KCl-UCl3 at 500 °C. Also, the morphology and component of the recovered U residue by distillation of the cathode product was examined by FE-SEM and EDS analyses. 相似文献
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