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161.
报道了树状结构的手性联二萘酚(BINOL)配体的合成及其在二乙基锌对醛的不对称加成反应中的应用.(R)-2,2′-二羟基-1,1′-联萘-3,3′-二羧酸与末端为氨基的Frechet聚芳醚型树状分子经缩合反应,以中等产率得到0~3代的树状分子配体,用1HNMR,IR和MALDI-TOF质谱进行了结构表征.这些树状手性配体与Ti(OPri)4在无水甲苯溶液中形成的配合物是二乙基锌对醛不对称加成反应的高效催化剂,树状分子载体的体积对催化剂的对映选择性没有明显的影响.以邻氯苯甲醛为底物时,反应的对映选择性随树状分子代数的增加而有所提高.  相似文献   
162.
王建军  王立  王学杰 《化学进展》2003,15(5):409-419
高度支化状二茂铁基聚合物具有丰富的拓扑结构形态和独特的电、磁、催化和氧化还原性能,而且这类材料具有独特的流动性能、低的粘度和进一步的可反应性,从而使得它们展现出良好的应用前景,开发二茂铁基功能高分子材料正日益受到重视.本文介绍高度支化状二茂铁基聚合物的合成、结构、性能以及应用的研究进展.  相似文献   
163.
树枝状多氨基环氧树脂固化剂的合成及其固化行为   总被引:4,自引:0,他引:4  
树枝状多氨基环氧树脂固化剂的合成及其固化行为;树枝状大分子;丙烯酸酯双键;乙二胺(EDA)  相似文献   
164.
胡方中  杨华铮 《有机化学》2000,20(5):623-628
综述了近年来液相组合合成的研究进展,主要包括液相组合合成法(LPCS),氟合成,树状载体组合合成及高分子辅助试剂在液相组合合成中的应用等。  相似文献   
165.
A novel estrogen dendrimer has been synthesized through a combination of divergent and convergent approaches in 9 practical steps and in good yields.It was characterized and confirmed by elemental analysis,FT-IR,MS,1H NMR,13C NMR.The dendrimer contains 16 estrone units and is potentially a useful tool for the studies of estrogen actions.  相似文献   
166.
《中国化学》2014,(1):91-96
Novel biodegradable dendritic contrast agents (DCAs) based on polyester dendrimers were synthesized and characterized.The DCAs were stable at acidic pH,but hydrolyzed rapidly at physiological pH,which rendered the DCA's long-term Gd3+ retention as low as that of small molecule CAs.Their longitudinal relaxivities of 10.2 to 17.5 L·mmol-1·s-1 were about 2.4 to 4.1 times higher than that of DTPA-Gd,indicating their superior contrast-enhancing capability to the clinically used contrast agent.The in vivo MRI study suggested that the DCA at lower generation (G2-DTPA-Gd) could effectively enhance the MRI of tumor,while the one at higher generation (G5-DTPA-Gd) showed more potential in liver imaging.  相似文献   
167.
168.
In this article, dendronized polymers with rigid backbones were synthesized from enediyne‐containing Frechet‐type dendrimers. Two generations of dendrimers were conically incorporated with 3‐(2‐(2‐(trimethylsilyl)ethynyl)phenyl)prop‐2‐yn‐1‐ol. The trimethylsilyl protection groups of enediyne units were subsequently removed, and two types of brush polymers with rigid conjugated backbone were prepared through Bergman cyclization polymerization at elevated temperature under vacuum. The dendronized polymers were characterized with GPC, IR, UV–vis, and NMR spectroscopy. Furthermore, the morphology of the dendronized polymer was revealed by atomic force microscopy. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   
169.
Junzhu Pan  Lifang Ma  Bo Li  Yanhua Li 《合成通讯》2013,43(23):3441-3454
Abstract

Novel bone-targeting prodrugs containing dendritic naproxen and poly(aspartic acid) oligopeptide were synthesized in a convergent approach and were characterized by NMR, mass spectral, and elemental analysis techniques. The modified naproxen prodrugs showed a high affinity to hydroxyapatite in vitro and provided an effective entry for the synthesis of a dendritic naproxen–poly(aspartic acid) oligopeptide conjugates used for bone targeting.  相似文献   
170.
Supramolecular nano‐assemblies that reduce nonspecific interactions with biological macromolecules, such as proteins, are of great importance for various biological applications. Recently, zwitterionic materials have been shown to reduce nonspecific interactions with biomolecules, owing both to their charge neutrality and their ability to form a strong hydration layer around zwitterions via electrostatic interactions. Here, new triazole‐based zwitterionic moieties are presented that are incorporated as the hydrophilic functionalities in facially amphiphilic dendrons. The amphiphilic zwitterionic dendrons spontaneously self‐assemble in aqueous solutions forming micelle‐type aggregates, which were confirmed by DLS, TEM, and fluorescence techniques. The structural and functional characteristics of the zwitterionic dendrons are also compared with the corresponding charge‐neutral PEG‐based dendrons and anionic carboxylate‐based dendrons. Surface‐charge measurements, temperature sensitivity and evaluation of interactions of these assemblies with proteins form the bases for these comparisons.  相似文献   
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