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81.
林旭锋  王彦广 《有机化学》2005,25(10):1157-1166
随着组合化学的迅速发展, 兼容固相合成和溶液相合成优点的液相合成方法已成为实现组合化学的一条重要途径. 综述了近年来聚乙二醇为可溶性聚合物载体支载的杂环化合物库的研究, 并展望了其今后的发展方向.  相似文献   
82.
研究9种带有芳香稠环或杂环基团的光致变色螺吡喃化合物的光致变色性能和荧光性质.通过紫外-可见吸收光谱和荧光光谱对该类化合物与DNA相互作用性能进行了初步探讨.  相似文献   
83.
1,2- and 2,1-benzothiazines, for example, 1,2-benzothiazine-1,1-dioxides. 2,benzothiazine-2,2-dioxides, 1-alkyl/aryl-1,2-/2,1-benzothiazine-S-oxides, dibenzothiazine and polyheterocycle containing benzothiazine moiety are considered to be one of the privileged heterocyclic scaffolds with huge importances both in synthetic organic chemistry and medicinal chemistry especially in the drug industry. Numerous pioneering methodologies for asymmetric and non-asymmetric scaffold constructions have been developed. Comprehensive visions of different powerful methodologies for the synthesis of these scaffolds have been presented in this review.  相似文献   
84.
Phytochemical screening of nonpolar fractions from the methanol extract of the Bamboo shoot skin Phyllostachys heterocycla var. pubescens resulted in the isolation of a new sterol-glucoside-fatty acid derivative (6’-O-octadeca-8″,11″-dienoyl)-sitosterol-3-O-β-d-glucoside (1), together with six known compounds. The chemical structures of the pure isolated compounds were deduced based on different spectral data. The isolated compounds were assessed to determine their cytotoxic activity, and the results were confirmed by determining their apoptotic activity. Compound 1 was more cytotoxic against the MCF-7 cells (IC50 = 25.8 µM) compared to Fluorouracil (5-FU) (26.98 µM), and it significantly stimulated apoptotic breast cancer cell death with 32.6-fold (16.63% compared to 0.51 for the control) at pre-G1 and G2/M-phase cell cycle arrest and blocked the progression of MCF-7 cells. Additionally, RT-PCR results further confirmed the apoptotic activity of compound 1 by the upregulation of proapoptotic genes (P53; Bax; and caspases 3, 8, and 9) and downregulation of the antiapoptotic genes (BCL2). Finally, the identified compounds, especially 1, were found to have high binding affinity towards both tyrosine-specific protein kinase (TPK) and vascular endothelial growth factor receptor (VEGFR-2) through the molecular docking studies that highlight its mode of action.  相似文献   
85.
Single crystals of two achiral and planar heterocyclic compounds, C9H8H3O(CA1) and C8H5NO2 (CA4), recrystallized from ethanol, were characterized by single crystal X-ray analysis, respectively, and chiral crystallization was observed only for CA1 as P212121 (# 19), whereas it was not observed for CA4 P21/c (# 14). In CA1, as a monohydrate, the hydrogen bonds were pronounced around the water of crystallization (O4), and the planar cyclic sites were arranged in parallel to slightly tilted positions. On the other hand, an anhydride CA4 formed a dimer by hydrogen bonds between adjacent molecules in the crystal, which were aggregated by van der Waals forces and placed in parallel planar cyclic sites.  相似文献   
86.
Synthesis of novel 4-(4-methylsulfonylphenyl)-3-phenyl-2(3H)-thiazole thione derivatives with functionalized diarylheterocycle pharmacophore as potential COX-2 inhibitors was described. The title compounds were synthesized by cyclocondensation of corresponding dithiocarbamate and 2-bromo-1-(4-methylsulfonylphenyl)ethanone, followed by dehydration with H2SO4. All of the target compounds were characterized by ^1H NMR, IR and mass spectral data.  相似文献   
87.
We report the first general synthesis of boron‐substituted monobenzofused 1,4‐azaborines using ring‐closing metathesis of an enamine‐containing diene as a key synthetic strategy. As part of our investigations, we discovered that the B‐C3 moiety in a 1,4‐azaborine can serve uniquely as a η2‐L‐type ligand. This functionality is exemplified by two κ2N‐η2‐BC Pt complexes of a boron‐pyridyl‐substituted monobenzofused‐1,4‐azaborine. Single‐crystal X‐ray diffraction analysis of the Pt complexes shows a strong structural contribution from the iminium resonance form of the monobenzofused‐1,4‐azaborine ligand. We also demonstrate that a palladium(0) complex supported by a 1,4‐azaborine‐based phosphine ligand can catalyze hydroboration of 1‐buten‐3‐yne with unique selectivity. In view of the importance of arene–metal π‐interactions in catalytic applications, this work should open new opportunities for ligand design involving the 1,4‐azaborine motif as an arene substitute.  相似文献   
88.
制备了聚({4,8-双[(2,5,8,11,14,17,20-七氧二十二烷-22-基)氧基]苯并[1,2-b∶4,5-b']二噻吩}-交替-[2,5-二(噻唑-2-基)吡嗪])(P7O-2N-2N)和聚({4,8-双[(2,5,8,11,14,17,20-七氧二十二烷-22-基)氧基]苯并[1,2-b∶4,5-b']二噻吩}-交替-[3,6-双(5-溴-2-噻吩基)-1,2,4,5-四嗪])(P7O-4N)2个亲水性共轭聚合物, 通过调节主链含氮杂环上氮原子的位置, 系统研究了主链结构对材料吸收光谱、 能级、 氢结合自由能及光催化性能的影响. 研究发现, 与P7O-2N-2N相比, P7O-4N表现出更强的链间聚集、 更低的氢结合自由能及更好的光催化制氢性能.  相似文献   
89.
肼类衍生物在五元唑类杂环合成中的应用进展   总被引:6,自引:0,他引:6  
张自义  张艳  惠新平  许鹏飞  沈大鹏 《有机化学》2004,24(11):1348-1365
简要概述了肼类衍生物的结构及反应活性,总结了近十年来肼类衍生物分别在合成五元唑类杂环如吡唑、噻唑、1,3,4-噁二唑、1,3,4-噻二唑以及三唑类化合物,及其相关的稠杂环如吡唑并某环、s-三唑[3,4-b][1,3,4]-噻二唑、s-三唑[3,4-b][1,3,4]-噻二嗪,以及含有1,2,4-三唑的稠杂环化合物等合成中的应用进展.  相似文献   
90.
The C? H functionalization strategy has received substantial attention because of its economic, sustainable and environmentally benign features. Most reports are on palladium, rhodium or ruthenium catalysis, and reports on copper catalysis are relatively fewer. Recently, many reports on copper‐catalyzed/mediated C? H functionalization have been published. Copper salts bear properties of cheapness and relatively low toxicity. This review introduces an advance on copper‐catalyzed/mediated aromatic C? H functionalization. The content includes aromatic ring C? H bond functionalization and heteroaromatic C? H bond functionalization forming new carbon–carbon or carbon–heteroatom bonds. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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