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合成了一个新的超分子聚合物{(MAH+)2(p-BDOA2-)·4H2O}n(MA=三聚氰胺;p-BDOAH2=对苯二氧乙酸),通过X-射线对其结构进行了表征。在该聚合物中,三聚氰胺被质子化,相邻的三聚氰胺分子通过氢键形成一维阳离子链(MAH+)n,相邻的阳离子链由p-BDOA2-阴离子连接构成波浪状的二维层,层状结构通过水分子的氢键和π-π堆积形成三维结构。  相似文献   

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Reactions of 4-aminofurazan-3-carboxylic acid iminoester with o-aminophenol and ethylenediamine give rise respectively to 4-(1,3-benzoxazol-2-yl)- and 1-(4,5-dihydro-1H-imidazol-2-yl)-1,2,5-oxadiazol-3-amines, with aminoethanol arises 2-[(Z)-1-amino-1-(4-amino-1,2,5-oxadiazol-3-yl)methylideneamino]-1-ethanol. Treating of 3-amino-4-(1H-benzo[d]imidazol-2-yl)-1,2,5-oxadiazole with triethyl orthoformate in acetic anhydride yielded benzo[4,5]imidazo[1,2-c][1,2,5]oxadiazolo[3,4-e]pyrimidine, and alkylation with haloalkanes furnished 3-amino-4-(1-R-benzo[d]imidazol-2-yl)-1,2,5-oxadiazoles.  相似文献   

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1H-吲唑-3-羧酸的合成   总被引:1,自引:0,他引:1  
王燕  黄海洪  饶尔昌  张曼云 《合成化学》2005,13(1):16-21,28
综述了1H-吲唑-3-羧酸的合成方法,并评述了其优缺点;同时介绍了作者在寻找其新合成方法中的一些探索。参考文献28篇。  相似文献   

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合成了系列新的3-芳基噻唑烷-4-酮-2-酰胺衍生物,并测试了化合物抑制肿瘤细胞增殖活性.部分化合物对A-549和Hela肿瘤细胞有弱的细胞毒性,而对BGC-823没有抑制作用,表现出一定的选择性.其中,化合物7ad对A-549有较强的抑制活性(IC50=21.0μmol·L-1),与阳性对照顺铂的抑制活性(IC50=19.4μmol·L-1)相当.初步的构效关系表明化合物的立体结构可能对其抗肿瘤活性影响较大.  相似文献   

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氨基酸类化合物如氨基乙酸、亚氨基二乙酸和氨基三乙酸等胺多羧酸有多个配位点 ,可以多种方式和金属离子配位 ,从而得到多种形式的簇合物及一维、二维或三维晶体结构 .我们已经得到了氨基乙酸、亚氨基二乙酸或氨基三乙酸等与稀土和铜的异核配合物 ,并研究了它们的晶体结构[1~ 3] .为深入研究胺多羧酸类配合物的结构特点以及苯环的存在对晶体结构的影响 ,本文合成了一种新型的氨基多羧酸类配合物 N-苯胺叉二乙酸与铜的配合物 ,并测定了其晶体结构 .1 实验部分1 .1 配体 N -苯胺叉二乙酸 [C6H5N ( CH2 COOH) 2 ,H2 L ]的合成 将 5 .…  相似文献   

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B3LYP and MP2 methods with the most popular basis set, 6-311++G(d,p) are applied to optimize the equilibrium conformers of 4-amino-3-pentene-2-thial. Furthermore, to have more reliable energies, the total electron energies of all forms are recomputed at the CBS-4M level of theory. A theoretical investigation of the equilibrium conformers clearly shows that various intramolecular hydrogen bonds (IHBs) such as N–H...S, S–H...N, S–H...π, C–H...N, and C–H...S are the most effective factors in the conformational preference of thialamine, thiolimine, and thialimine groups. Hence, the IHB strengths are evaluated in various resonance-assisted hydrogen bond systems by geometrical factors, topological parameters, and charge transfers corresponding to orbital interactions. Also, the solvent effect on the IHB strength is considered using Tomasi′s PCM. Our results in the gas phase reveal that the thialamine group has extra stability with respect to thiolimine and thialimine ones. The population analyses of all the possible conformers by the NBO method predict that the origin of this tautomeric preference is mainly due to more significant π electron delocalization in the framework of thialamine forms, especially πC=C → π C = S* and Lp(N) → π C = C* charge transfers. Moreover, the excited state properties of IHBs in these systems are investigated theoretically using the time-dependent DFT method.  相似文献   

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Based on cryogenic FT-IR spectroscopic studies of hydrogen bonds in cholic acid, two-dimensional FT-IR spectroscopy was applied to enhance our understanding of the hydrogen bonds of cholic acid. Fine spectral structures were revealed by asynchronous 2D FT-IR spectra. The co-relationship among various bands was discussed according to the synchronous 2D FT-IR spectrum.  相似文献   

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N-Methylcarbazole-3-carboxylic acid was synthesized from N-methyl-2-amino-4-carboxydiphenyl-amine through the corresponding diazo compound by a modified Pschorr procedure. The acid was converted into N-methylcarbazole-3-carbonyl chloride which was treated with amines containing benzo- and aza-crown ether moieties, as well as with 3-(dimethylamino)propylamine, to obtain the respective N-substituted amides.  相似文献   

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