大二环型侧向穴醚的合成

本文报道一个大二环型侧向穴醚的合成方法借2,6-二(溴甲基)吡啶与β-(N-对甲苯磺酰基)丙氨酸酯缩合,产物经水解成酸后转换为酰氯(8),8借高度稀释法与1,7-二氮杂-4,10-二硫杂环十二烷(5)缩合成环,然后还原羰基.脱对甲苯磺酰基后得大二环型侧向穴醚1,5,13,17,28-五氮杂-20,25-二硫杂-三环[15,5,5,1~(7,11)]-廿八-7,9,11(28)三烯(2).     

基于酰胺的荧光双冠醚阴离子受体的合成和识别性能研究

合成了一种带有荧光基团蒽的酰胺型双冠醚阴离子受体3. 用荧光光谱、紫外-可见吸收光谱及核磁共振氢谱研究了其与F^－, Cl^－, Br^－, I^－, H₂PO₄^－, AcO^－离子的相互作用, 结果表明3只对F^－具有很好的选择性识别能力, 并形成配合比为1∶2的络合物, 通过荧光发射强度计算出主体3与F^－间的相互作用时的结合常数.     

多分支中性受体的合成及αω-二羧酸阴离子识别研究

Two new multi-armed neutral receptors 1 and 2 containing thiourea and amide groups were synthesized by simple steps in good yields. Receptors 1 and 2 have a better selectivity and higher association constants for malonate anion than other anions examined by the present work. In particular, distinct color changes were observed upon addition of dicarboxylate anions to the solution of 1 in DMSO. The UV-Vis and fluorescence spectra data indicate that a 1 ： 2 stoichiometry complex was formed between compound 1 or 2 and dicarboxylate anions of shorter carbon chain, and a 1 ： 1 stoichiometry complex was formed between compound 1 or 2 and dicarboxylate anions of longer carbon chain through hydrogen bonding interactions.     

α-唑基-α-芳氧烷基频哪酮(芳乙酮)及其醇式衍生物的合成和生物活性研究

对α－唑基－α－芳氧烷基频哪酮（芳乙酮）及其醇式衍生物的合成和生物活性进行了研究，合成了３３个新型化合物，所有化合物的结构均经核磁共振和元素分析证实；初步的生物活性测试结果表明，该类化合物具有一定的杀菌活性和植物生长调节活性．     

Calix[4]arenes containing thiourea and amide moieties: neutral receptors towards alpha,omega-dicarboxylate anions

Two-armed neutral anion receptors (4,5), were prepared and examined for their anion-binding ability using UV-vis, fluorescence and 1H NMR spectra in DMSO. The results of non-linear curve fitting indicate that 4 or 5 form 1 : 1 stoichiometric complexes with dicarboxylate anions by multiple hydrogen bonding interactions and the sensitivity for recognition of dicarboxylate depends on the chain length of these dicarboxylate anions. Receptors 4 and 5 have no binding ability with acetate, dihydrogen phosphate and the halogen (Cl-, Br-, I-) anions. This demonstrates that receptors 4 or 5 could be used as chemical sensors for some special dicarboxylate anions.     

Amide-based Fluorescent Macrocyclic Anion Receptors

Introduction Interest in the selective recognition and sensing of anionic species continues to attract the attention of su-pramolecular chemistry community.1 The importance of anions in chemical and biological process can not be underestimated. It is well known that in nature neutral proteins bind anions only via hydrogen bonding interac-tions.2 Several anion receptors have been constructed from five-membered heterocycle,3 amide,4 (thio) urea,5 since these groups form relatively strong NHanio…     

含吡啶环系和中心功能基氮杂冠醚的合成研究

合成了氮杂大环化合物Ⅰ－Ⅳ，并通过＾１Ｈ ＮＭＲ、ＭＳ和元素分析表征了它的结构，对其中间体（７）的合成方法进行了改进，使收率得到了大幅度提高，探讨了在不同温度下的成环反应，结果表明，室温有利于成环和提高反应收率。     

Synthesis, pharmacokinetics and in vivo antifungal activity of the novel water-soluble prodrugs of itraconazole analogue YL-24

To improve the aqueous solubility of an itraconazole analogue,compound 1(YL-24),a series of novel prodrugs were synthesized.Among these prodrugs,the phosphate disodium salt compound 7 exhibited excellent aqueous solubility(9.8 mg/mL) at near-neutral pH and sufficient stability in buffer solutions, along with favorable pharmacokinetic profiles.In particular,compounds 1 and 7 provided moderate survival efficacy in murine systemic Candida albicans SC5314 infection model,but their efficacy was weaker than that of fluconazole.     

Si在TiAl3中取代行为的第一性原理研究

采用基于密度泛函理论的第一性原理方法,研究了Si原子在TiAl₃中的格点取代行为.通过对不同原子被置换后的c/a值、形成能以及电子态密度的计算和比较,发现Si原子倾向于取代TiAl₃中的Al原子,其取代行为主要由系统的电子结构决定,计算结果与实验相符.为了进一步研究Si原子的取代行为,对Si原子占据的格点以松散或紧凑分布下体系的总能、形成能以及电子态密度进行了计算,结果表明Si原子倾向于取代TiAl₃中松散分布的Al（2）原子.对c/a值的计算表明,随Al（2）格点Si原子浓度的增加,c/a值逐渐增大;而当Si取代Al（1）格点时,c/a值随Si原子浓度的增加而减小.研究表明,Si在TiAl₃中的极限固溶度介于12.5at%—18.75at%之间. 关键词： 密度泛函理论 第一性原理 电子结构 3')" href="#">TiAl₃     

电子型掺杂高温超导体La2-xCexCuO4飞秒时间分辨动力学研究

利用飞秒时间分辨光抽运探测技术研究了电子型掺杂La2-xCexCuO4(LCCO)高温超导材料的准粒子超快动力学过程.得到低温(T＜0.7Tc)、转变温度附近(0.7Tc≤T≤Tc)和高温(T＞Tc)三个温区内的动力学行为.研究发现,低温时准粒子寿命随温度上升而下降,接近转变温度时出现反常的上升,正常态准粒子寿命受赝能隙影响明显大于金属中电声子的弛豫时间.还发现电子型掺杂LCCO光感生反射率变化△R/R动力学曲线存在皮秒量级的上升过程,它反映Cooper对被打散的时间较长,上升时间随温度增加而变短.采用Rothwarf和Taylar提出的理论模型对实验结果进行了分析.