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1.
李新红  方鹏飞  陈远荫 《有机化学》2001,21(10):721-727
介绍了[60/70]富勒烯与杯[8],[6],[5]芳烃、高氧杂杯[3]芳烃及双杯芳烃形成包合物的研究进展和应用前景。  相似文献   

2.
多重氮杂杯[4]芳烃和双杯[4]芳烃的合成与阳离子萃取性能;杯[4]芳烃;双杯[4]芳烃;多重氮杂;萃取  相似文献   

3.
王梅祥 《化学进展》2018,30(5):463-475
本文介绍了杂杯芳烃和冠芳烃的研究起源,总结了杂杯芳烃和冠芳烃的设计与合成、构象和大环空腔结构特征,展示了杂杯芳烃和冠芳烃的分子识别和组装性质,概述了杂杯芳烃和冠芳烃在功能材料的制备中的应用,展望了大环超分子化学未来的发展方向。  相似文献   

4.
张光瑞  张文芬  郭云  张素宁  张书胜 《色谱》2020,38(4):392-398
杯芳烃是一类由苯酚单元通过亚甲基桥连的超分子化合物,具有独特的主客体识别性能,是继冠醚和环糊精之后第三代超分子化合物的主要代表。其被广泛应用于离子通道、有机催化反应、跨膜转运、纯化、色谱分离等方面。基于杯芳烃易于修饰的特点,选取不同性质的化合物进行衍生化,可以制备出具有不同识别能力和高选择性的杯芳烃衍生物,进而应用于不同色谱分离模式,可实现复杂样品的分离分析。该文从杯芳烃、杯芳烃衍生物和杯杂芳烃3个方面综述了近年来杯芳烃在液相色谱固定相方面的研究应用及进展,并对杯芳烃在色谱分离领域的发展提出了展望。  相似文献   

5.
在普通杯芳烃骨架中引入硫原子可以改善普通杯芳烃的配合性能。文中首先合成了硫杂杯[4]芳烃四酰肼衍生物3,在弱酸的催化下继续与化合物4反应,高产率地合成了同时含酰胺和席夫碱单元的硫杂杯[4]芳烃冠醚衍生物5,新化合物的结构经1H NMR、元素分析、ESI-MS等表征证实。同时探讨了新型硫杂杯[4]芳烃衍生物5与系列-α氨基酸的配合性能。  相似文献   

6.
双杯芳烃是杯芳烃家族中的重要一员。它由两个杯芳烃单元通过化学键联结而形成,一般常有上缘-下缘、下缘-下缘、下缘-上缘3种桥联方式,其结构更复杂,性质也更为丰富多彩。双杯芳烃具有两个相同或不相同的结合部位,可同时络合两个相同或不相同的底物,还可表现出特殊的协同作用、更强的络合能力、变构象以及粒子雾荡等新的性质。本文根据杯芳烃亚单元的种类,综述了双杯芳烃的研究进展,重点描述了不同桥联方式的双杯[4]芳烃的合成方法,而且对一些具有特殊性能的双杯芳烃进行了较为详细的介绍。最后对双杯芳烃的发展前景作了展望。  相似文献   

7.
王浩  李喆  刘育 《中国科学B辑》2007,37(4):350-354
合成了一系列下缘含有杂原子的杯芳烃衍生物, 其晶体结构和核磁研究证实杯芳烃以锥式构象存在, 并且通过溶剂萃取法研究了它们对过渡金属和重金属的阳离子键合能力和选择性. 实验结果表明: 将氮、硫、磷等杂原子引入杯芳烃的下缘可以提高其对银、铅等重金属的萃取能力.  相似文献   

8.
硫杂杯[4]芳烃是由S原子取代经典杯芳烃中的桥联亚甲基而成的大环化合物,在分子识别、多核金属配合物、化学传感器等方面有广泛的应用.对硫杂杯[4]芳烃的化学修饰进行综述,有助于新型功能化硫杂杯芳烃衍生物的研究.  相似文献   

9.
硫杂杯[4]芳烃酰胺基硫脲衍生物的合成   总被引:1,自引:1,他引:0  
黄翠玉  杨发福  赵夏  郭红玉  林建荣 《合成化学》2006,14(3):264-265,268
硫杂杯[4]芳烃四乙酸乙酯衍生物与水合肼反应生成硫杂杯[4]芳烃四酰肼衍生物(3),3与异硫氰酸苯酯反应得到新型硫杂杯[4]芳烃酰胺基硫脲衍生物,总产率61%。  相似文献   

10.
综述了含杂原子杯芳烃的结构、命名方法、合成方法等方面的研究进展.指出在超分子化学领域,杯芳烃骨架结构的改变是杯芳烃研究的热点之一;与传统杯芳烃相比,在杯芳烃分子骨架中引入桥联杂原子或芳杂环后,不仅使得其在结构和分子识别方面产生新颖变化,而且使得其合成方法也发生巨大改变.  相似文献   

11.
This review focuses on key topics in the field of drug delivery related to the design of nanocarriers answering the biomedicine criteria, including biocompatibility, biodegradability, low toxicity, and the ability to overcome biological barriers. For these reasons, much attention is paid to the amphiphile-based carriers composed of natural building blocks, lipids, and their structural analogues and synthetic surfactants that are capable of self-assembly with the formation of a variety of supramolecular aggregates. The latter are dynamic structures that can be used as nanocontainers for hydrophobic drugs to increase their solubility and bioavailability. In this section, biodegradable cationic surfactants bearing cleavable fragments are discussed, with ester- and carbamate-containing analogs, as well as amino acid derivatives received special attention. Drug delivery through the biological barriers is a challenging task, which is highlighted by the example of transdermal method of drug administration. In this paper, nonionic surfactants are primarily discussed, including their application for the fabrication of nanocarriers, their surfactant-skin interactions, the mechanisms of modulating their permeability, and the factors controlling drug encapsulation, release, and targeted delivery. Different types of nanocarriers are covered, including niosomes, transfersomes, invasomes and chitosomes, with their morphological specificity, beneficial characteristics and limitations discussed.  相似文献   

12.
There is currently a worldwide consensus and recognition of the undoubted health benefits of the so-called Mediterranean diet, with its intake being associated with a lower risk of mortality. The most important characteristics of this type of diet are based on the consumption of significant amounts of fruit, vegetables, legumes, and nuts, which provide, in addition to some active ingredients, fiber and a proportion of vegetable protein, together with extra virgin olive oil (EVOO) as the main sources of vegetable fat. Fish and meat from poultry and other small farm animals are the main sources of protein. One of the main components, as already mentioned, is EVOO, which is rich in monounsaturated fatty acids and to a lesser extent in polyunsaturated fatty acids. The intake of this type of nutrient also provides an important set of phytochemicals whose health potential is widely spread and agreed upon. These phytochemicals include significant amounts of anthocyanins, stilbenes, flavonoids, phenolic acids, and terpenes of varying complexities. Therefore, the inclusion in the diet of this type of molecules, with a proven healthy effect, provides an unquestionable preventive and/or curative activity on an important group of pathologies related to cardiovascular, infectious, and cancerous diseases, as well as those related to the metabolic syndrome. The aim of this review is therefore to shed light on the nutraceutical role of two of the main phytochemicals present in Olea europaea fruit and leaf extracts, polyphenols, and triterpenes, on healthy animal growth. Their immunomodulatory, anti-infective, antioxidant, anti-aging, and anti-carcinogenic capabilities show them to be potential nutraceuticals, providing healthy growth.  相似文献   

13.
以α位(2,4-二特戊基)苯氧基邻苯二腈作为环合前体,制备了多种金属酞菁,产物经元素分析、紫外、红外、核磁氢谱等分析手段进行表征.并选择了部分酞菁进行溴化,其中着重研究了不同中心金属以及溴化对染料Q带吸收的影响.结果表明,酞菁染料的金属化对于其Q带吸收影响很大,多数染料金属化后会出现蓝移,而选择合适的条件进行溴化,可以使得金属酞菁的Q带吸收出现一定程度的红移,其中部分溴化金属酞菁的吸收波长与光信息产业中使用的近红外激光器很接近,具有潜在的实用价值.  相似文献   

14.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

15.
Virola is the largest genus of Myristicaceae in America, comprising about 60 species of medium-sized trees geographically spread from Mexico to southern Brazil. The plant species of this genus have been widely used in folk medicine for the treatment of several ailments, such as rheumatic pain, bronchial asthma, tumors in the joints, intestinal worms, halitosis, ulcers, and multiple infections, due to their pharmacological activity. This review presents an updated and comprehensive summary of Virola species, particularly their ethnomedicinal uses, phytochemistry, and biological activity, to support the safe medicinal use of plant extracts and provide guidance for future research. The Virola spp.’s ethnopharmacology, including in the treatment of stomach pain and gastric ulcers, as well as antimicrobial and tryponosomicidal activities, is attributable to the presence of a myriad of phytoconstituents, such as flavonoids, tannins, phenolic acids, lignans, arylalkanones, and sitosterol. Hence, such species yield potential leads or molecular scaffolds for the development of new pharmaceutical formulations, encouraging the elucidation of not-yet-understood action mechanisms and ascertaining their safety for humans.  相似文献   

16.
翟广玉 《化学通报》2021,84(12):1338-1344
芦丁属于类黄酮化合物,广泛存在于人们日常食用的各种蔬菜、水果和中草药中。 芦丁是天然的抗氧化剂,有清除自由基的特性,可调节众多疾病有关的细胞内和细胞外信号通路,影响细胞的生长,分化及其功能,对人们的健康,防病治病起着重要作用。芦丁具有广泛的药理活性,抗氧化、抗炎、抗病毒、抗癌、预防和治疗心脑血管疾病。以芦丁为原料的药品有多种,使用芦丁毒副作用小,安全,成本低。由于芦丁的生物利用度低,在临床上应用受到一定的限制。克服芦丁溶解性差的问题已经有各种方法,例如使用环糊精的络合,磷脂等,改善水溶性,从而增加生物利用度。本文综述了芦丁的多种潜在用途和治疗作用的信息,与药物输送相关的问题,以及改善药物生物利用度的可能方法。重点介绍了芦丁的抗炎、抗癌、降糖、对心血管的保护作用,为天然化合物的开发和利用奠定基础。  相似文献   

17.
Microwave (MW) digestion procedures with high sample throughput (simultaneous digestion of 36 or 80 samples) and procedural simplicity (disposable plastic tubes, or re-usable liners with screw-cap) were investigated for their efficiency in routine analyses of biological samples. Different digestion vessel materials were tested for metal leaching/adsorption and thermal resistance: quartz, glass, polyethylene (PE) and polystyrene (PS). For the instrumental quantification of Al, Bi, Cd, Co, Cr, Hg, Mn, Mo, Ni, Pb, Sb, and Tl at ultra-trace levels in urine, serum, and whole blood, sector field inductively coupled plasma mass spectrometry (SF-ICP-MS) was used. The different pretreatment conditions and vessels were evaluated in terms of contamination risk, effective power of detection, accuracy, and precision. Results of analyses of serum, urine and whole blood certified reference materials (CRMs) were fully satisfactory for almost all the analytes. In the case of Hg, Mo, and Tl in serum digested in plastic containers the results were just below the lower limit of uncertainty of the certified range. On the basis of the present data the following MW procedures can be suggested: 1. for urine, digestion with nitric acid at atmospheric pressure in plastic vials; 2. for serum, digestion with nitric acid at atmospheric pressure in glass vessels; and 3. for whole blood, digestion under pressure in quartz tubes.Because of the levels of the procedural blanks, Bi was not measurable at the concentrations expected in human fluids, and Al was accurately detectable in whole blood only.  相似文献   

18.
田圆  赵倩莹  胡靖  周辰  缪灵  江建军 《化学进展》2012,24(4):512-522
大面积高质量石墨烯的制备对石墨烯电子特性及石墨烯基纳器件相关研究有重要意义。本文综述了近几年来衬底上制备石墨烯的相关实验以及衬底与石墨烯相互作用研究的重要进展。目前,采用化学气相沉积、外延生长等方法可在衬底表面上制备出较大面积、高质量的石墨烯材料。衬底与石墨烯相互作用和界面间晶格匹配、原子成键及电荷转移等密切相关,其对吸附石墨烯的几何结构、能带结构及电子特性等产生明显影响。实验与理论计算的结合可望加深衬底与石墨烯作用机理的理解,指导衬底上石墨烯制备及改性的进一步研究。  相似文献   

19.
张金凤  李萍  马玖彤  贾琼 《色谱》2021,39(2):173-183
农药的研发与使用极大地提高了农作物的产量,为解决人类温饱、改善人类生活品质做出了贡献。但是,农药广泛残留于农副产品以及土壤和水体中,造成的污染日趋严重。残留的农药通常具有微量致毒、难生物降解、生物累积等特性,对生物健康与生态系统造成了巨大威胁。高效检测微量农药、减小污染危害是亟待解决的问题。吸附法具有成本低、操作简单、稳定性强、可重复性强的特点,在农药分离预富集领域得到了广泛关注。作为一种常用的农药吸附剂材料,环糊精是一类具有空腔的超分子化合物,能够作为主体通过主客体作用形成包合物;另外,可以通过醚化、酯化、氧化等化学反应对环糊精进行后修饰以提高其吸附性能。疏水作用、静电作用、范德华力、氢键作用、立体效应协同促进对农药的吸附。环糊精在农药吸附领域已经取得了一定进展,但是目前还没有基于环糊精的农药吸附剂的综述。该文针对杀菌剂、杀虫剂、除草剂、植物生长调节剂这4类农药,系统性地评述了基于环糊精的农药吸附剂的制备、吸附机理及应用,目前存在个别吸附剂吸附容量不高、降解机理不明确、降解产物对环境不友好、容易造成二次污染的问题,研发高吸附容量、易回收、易分离、易再生的基于环糊精的农药吸附剂是未来的主要研究方向。  相似文献   

20.
The supramolecular chemistry of cucurbituril, a synthetic receptor, is fascinating because of the remarkable guest binding behavior of the host. Although cucurbituril is potentially as useful as crown ethers, cyclodextrins, and calixarenes in many applications, its chemistry has not been developed much until recently because of several shortcomings. Recently we synthesized cucurbituril homologues and derivatives. These new members of the cucurbituril family have expanded the scope further, and interest in them has grown enormously. The diversity in guest binding behavior has led to many interesting studies such as redox control of guest binding, stabilization of charge-transfer complexes inside the host cavity, encapsulation of drug molecules, formation of redox-controllable vesicles, and so on. The cucurbituril homologues and derivatives thus provide new opportunities in many areas of supramolecular chemistry including recognition, catalysis, separation, transport, and many others.  相似文献   

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