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1.
A series of monobridged calix [4] arenes 3a-f,cyclic biscalix-[4] arenes 4a-f ,diametrically bridged at the upper rim with saturated aliphatic diester chians,have been synthesized,The results at diluted conditions show that the percentage of yields of mono-,bis- and oligo-calix[4] arenes are related to the legth of the chains ,With the shortening of the chains ,the percent-age of monocalix[4] arenes decreased ,All the calix [4] arene moieties are in a cone conformaiton according to the AB quar-tet pattern of the methylene protons between the phenolic rings in the ^1H NMR spectra.  相似文献   

2.
手性杯芳烃的合成及性质   总被引:2,自引:0,他引:2  
田振峰  郑炎松 《有机化学》2002,22(10):702-709
手性杯芳烃是一类重要的主体化合物,在手性识别、对映体分离、不对称催化 等方面有潜在的用途、综述了手性杯芳烃的合成及其在手性识别、对映体分离方面 的性能。  相似文献   

3.
杯芳烃包合作用的研究进展   总被引:7,自引:1,他引:6  
高博  冯亚青  周立山  马骧 《有机化学》2004,24(7):713-721,J001
综述了杯芳烃包合作用的研究进展,详细介绍了其对碱金属离子、过渡金属离子、副族金属离子等离子的包合作用和对染料、卟啉、富勒烯、聚合物等有机中性分子的包合作用,并对其应用前景进行了展望.  相似文献   

4.
单取代杯[6]芳烃衍生物的合成与表征   总被引:3,自引:0,他引:3  
杨发福  陈远荫  林深 《有机化学》2002,22(10):746-749
系统地研究了在各种不同反应体系与条件下杯[6]芳烃与含酯基、环氧基、溴 代烷基等活性基团化合物的选择性功能化反应行为,发现分别在K2CO3/甲苯以及 KOH/乙腈体系中能以较好产率得到了具酯基、环氧基、溴代烷基的单取代杯[6]芳 烃高分子单体。  相似文献   

5.
With the expectation to prepare a new type of heteroditopic host, a series of calix[4]arenes modified with germanium‐containing side chains at the upper rim was prepared. Compounds 1 and 2 bear two or four triethylgermyl moieties respectively, and compounds 3 and 4 bear two or four trimethylgermyl moieties respectively. For 1 and 2 , the hydroxy groups at the lower rim are either tosylated (series a) or kept free (series b). For reference, a carbon analog of 3 , compound 5 , was also prepared. Unfortunately, all calixarenes prepared failed to show any appreciable cation transport property, indicating that the structure designed, i.e. a calixarene with germanium‐containing side chains at the upper rim, cannot meet the requirement for an appropriate heteroditopic host. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

6.
杯芳烃——一类具有发展前景的大环化合物   总被引:1,自引:0,他引:1  
本文介绍了杯芳烃这类新型的大环化合物,并着重对其制法、构象、络合特性及在阳离子输送、选择性络合和酶模拟等方而的应用进行了评述。  相似文献   

7.
The electrochemistry of calixarene as a redox-dependent ionophore and its structural dependence are described. One or more redox-centers such as quinone, ferrocene, cobaltocenium and ruthenium bipyridine moieties have been introduced into the calixarene frame of the lower or upper rim. Although the electrochemical behavior depends mainly on the inherent redox property of these electrochemically active groups, the structural effect and solvent also play important roles, especially, in the presence of charged guests. When cationic species such as metal ions and ammonium ion are added to a quinone-functionalized calixarene solution, electron transfer to quinone is enhanced by the electrostatic effect or the formation of hydrogen bonds. In addition to redox-active hosts for voltammetric use, a number of calixarenes with novel structures have been developed as ionophores for potentiometric analysis and found to be successful for some target ions. In terms of Na+, Cs+ and Ca2+ selective ionophores for ion-selective electrodes, calixarenes are found to be excellent compared to crown ether derivatives or cryptands. Calixarenes can be also utilized to construct chemically modified electrodes, which are sensitive to gas species and biologically important compounds. The sophisticated design and synthesis of calixarenes are essential to specific potential applications to diverse fields.  相似文献   

8.
A potential hypoxia-sensitive system host-guest complex of three calixarenes (including two with four anionic carboxyl and sulphonate azo fragments on the upper rim and a newly synthesized bis-azo adduct of calixarene in the cone configuration with azo fragments on the lower rim with the most widespread cationic and zwitterionic rhodamine dyes (123, 6G and B)) was studied using UV-VIS spectrometry and fluorescence as well as 1D and 2D NMR techniques. It was found that all three calixarenes form a complex with rhodamine dyes with a 1:1 composition. The association constants of calixarene-dye complexes with sulfonate calixarenes, especially in the case of tetra-anionic calixarene, turned out to be higher compared with carboxyl calixarene due to the more intense electrostatic interactions. For the first time using an HRESI MS technique, it was shown that the treatment of rhodamine 6G and 123 with sodium dithionite (SDT) produces a non-fluorescent leuco form of the dye, and only rhodamine B can be used with SDT without the occurrence of a side reduction. Moreover, it was identified that in addition to the reduction in the azo groups, SDT causes partial cleavage of the aryl ether bonds. The found features of SDT should be taken into account when SDT is used as an azoreductase mimic.  相似文献   

9.
综述了络合阴离子的杯芳烃受体, 详细介绍了连有金属和Lewis酸的杯芳烃阴离子受体, 连有酰胺、脲、多胺的杯芳烃和杯吡咯等含氢键受体的阴离子受体, 并对其应用前景进行了展望.  相似文献   

10.
IntroductionCalixareneshavereceivedincreasingattentionduringthelastdecadesduetotheirabilitytoformhost guesttypecomplexeswithavarietyoforganicorinorganiccom poundsandtheirreadyaccessibilityaswell.1 3 Sulfonatedcalix[n]arenes (SCnA ,n =4 ,6 ,8)canforminclu sioncom…  相似文献   

11.
Fluorescence and absorption studies of water-soluble sulfonated calix[6]arene (SCX6) are reported. Water-soluble calixarenes are potentially useful as host molecules for luminophores, and studies of their spectroscopic characteristics are therefore crucial. The absorption and fluorescence spectra of these molecules in aqueous solution were collected, analyzed, and compared with 4-hydroxybenzene sulfonate at different pHs. A red shift in the absorption spectrum and a change in the fluorescence spectrum of the calixarenes are observed upon an increase in pH from 2.0 to 13.0. Some of these spectroscopic changes are attributed to intramolecular hydrogen bonding between adjacent hydroxyl groups of SCX6 after proton disassociation. The formation of excimers between phenolic groups in the calixarene molecule is proposed. In addition, inner-filter effects of SCX6 are discussed. These inner-filter effects prove to be a disadvantage for the use of SCX6 as a host molecule for complexation studies by use of fluorescence probes whose absorption spectra overlap with those of calixarenes.  相似文献   

12.
Methodologies to access water soluble large ringed calixarenes in good yield using efficient synthetic procedures have been investigated. Symmetrical partial functionalisations at the lower rim are described using activated [n]ethylene glycol chains and the addition behaviour contrasted with that of bromoalkanenitriles which proceeds with no observed regioselectivity. Full functionalisations of the calixarenes bearing hydrophilic groups are then investigated and a two-step procedure established which appears to be generally applicable for the addition of different [n]ethylene glycol chains. Furthermore, difunctionalisation under different reaction conditions are described. Throughout, strategies for the characterisation of these high mass compounds are outlined.  相似文献   

13.
Macrocyclic amphiphilic molecules based on calix[4]arenes are highly attractive for controlled supramolecular assembly of DNA into small nanoparticles, since they present a unique conical architecture and can bear multiple charged groups. In the present work, we synthesized new amphiphilic calixarenes bearing cationic groups at the upper rim and alkyl chains at the lower rim. Their self-assembly in aqueous solution was characterized by fluorescent probes, fluorescence correlation spectroscopy, dynamic light scattering, gel electrophoresis and atomic force microscopy. We found that calixarenes bearing long alkyl chains (octyl) self-assemble into micelles of 6 nm diameter at low critical micellar concentration and present the unique ability to condense DNA into small nanoparticles of about 50 nm diameter. In contrast, the short-chain (propyl) analogues that cannot form micelles at low concentrations failed to condense DNA, giving large polydisperse DNA complexes. Thus, formation of small DNA nanoparticles is hierarchical, requiring assembly of calixarenes into micellar building blocks that further co-assemble with DNA into small virus-sized particles. The latter showed much better gene transfection efficiency in cell cultures relative to the large DNA complexes with the short-chain analogues, which indicates that gene delivery of calixarene/DNA complexes depends strongly on their structure. Moreover, all cationic calixarenes studied showed low cytotoxicity. Thus, this work presents a two-step hierarchical assembly of small DNA nanoparticles for gene delivery based on amphiphilic cone-shaped cationic calixarenes.  相似文献   

14.
氧杂同杯芳烃的研究进展   总被引:2,自引:0,他引:2  
氧杂同杯芳烃是杯芳烃家族中重要一员 .综述了近年来氧杂同杯芳烃的合成、构象、衍生化以及它们的性质等方面的研究进展  相似文献   

15.
Heteroatom-bridged calixarenes have been confined intothe unexplored frontier of the vast realm of the calixarene chemistry because of their syntheticdifficulty. Since we found facile one-step synthesis of thiacalix[4]arene, in which four methylenebridges of calix[4]arene are replaced by four sulfides, we have been engaged in the study on thisnew molecular platform regarding the improvements for the synthetic procedures, structuralanalyses, chemical modifications, and functional developments. In this review are describedthe results of our own study to demonstrate the potentials over the limits of the conventionalcalixarenes, putting emphasis on the indispensable role of the bridging sulfur. Highlighted examples are(1) enlargement of the calix skeleton to provide larger cavity, (2) ready oxidizability to sulfoxideand sulfone for providing new members of S bridged calixarenes, and (3) coordination to specificmetal ions controlled by the oxidation state of S. These indicate a hopeful future for thethiacalixarene platform in the forthcoming applications to functional molecular devices.  相似文献   

16.
杯芳烃类受体的分子识别作用研究进展   总被引:6,自引:0,他引:6  
综述了杯芳烃类人工受体的分子识别作用的研究进展。主要介绍通过非共价键作用引起的识别-配合与识别-催化作用。  相似文献   

17.
Two new chiral calix[4] arenes bearing chiral pendants,which were from by-product of the antibiotic industry,were synthesized and characterized by ^1H NMR.MS-FAB and elemental analysis,Studies of ^1H NMR of the two calix[4] arene derivatives indicate that they exist in cone conformation in solution.Results of chiral recognition of the two chiral ligands 2a and 2b towards the tartaric acid derivative 3 show that ligand 2a exhibited good chiral recognition abilities compared to ligand 2b.  相似文献   

18.
韩军  颜朝国 《化学进展》2006,18(12):1668-1676
综述了杯芳烃衍生物对阴离子识别作用的研究进展。详细介绍了杯芳烃衍生物的化学结构修饰和分子结构以及其通过氢键和静电等作用对卤素、有机酸根、金属酸根等阴离子的识别作用,并对其应用前景进行了展望。  相似文献   

19.
Summary: The applications of calixarenes in polymer synthesis have been reviewed. Calixarenes have been used as ligands to prepare rare earth calixarene complexes. A series of rare earth calixarene complexes have been synthesized and employed as efficient catalysts for the polymerization of ethylene, styrene, butadiene, propylene oxide, styrene oxide, trimethylene carbonate, and 5,5-dimethyl trimethylene carbonate. On the other hand, the synthesis and characterization of star-shaped polymers with calixarene as core molecules are also described.  相似文献   

20.
Since cancer is a multifactorial disease with a high mortality rate, the study of new therapeutic strategies is one of the main objectives in modern research. Numerous chemotherapeutic agents, although widely used, have the disadvantage of being not very soluble in water or selective towards cancerous cells, with consequent side effects. Therefore, in recent years, a greater interest has emerged in innovative drug delivery systems (DDSs) such as calixarene, a third-generation supramolecular compound. Calixarene and its water-soluble derivatives show good biocompatibility and have low cytotoxicity. Thanks to their chemical–physical characteristics, calixarenes can be easily functionalized, and by itself can encapsulate host molecules forming nanostructures capable of releasing drugs in a controlled way. The encapsulation of anticancer drugs in a calixarene derivate improves their bioavailability and efficacy. Thus, the use of calixarenes as carriers of anticancer drugs could reduce their side effects and increase their affinity towards the target. This review summarizes the numerous research advances regarding the development of calixarene nanoparticles capable of encapsulating various anticancer drugs.  相似文献   

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