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1.
咪唑鎓本身带有正电荷,2-位碳氢(C2-H)具有一定的酸性,是一种良好的氢键供体,能与阴离子形成氢键。因此,咪唑鎓可以识别各种无机阴离子和生物体内重要的阴离子。本文利用四(1-咪唑甲基)甲烷的独特结构,通过烷基化反应,合成了多咪唑鎓盐2、含有多功能臂的双咪唑鎓盐3和咪唑鎓环番4。采用荧光发射光谱法研究了咪唑鎓盐2、3、4对阴离子(Cl~-、Br~-、I~-、CH_3COO~-、PhCOO~-、HSO_4~-)的光谱响应。结果表明,咪唑鎓盐2和咪唑鎓环番4a加入Cl~-,荧光强度明显增强;咪唑鎓盐3a加入PhCOO~-,荧光强度明显减弱;咪唑鎓盐3b和咪唑鎓环番4b加入I~-,荧光强度明显增强。  相似文献   

2.
以咪唑鎓正电荷为结构单元构筑的咪唑鎓型环番可发挥大环效应、范德华力、氢键、π-π堆积及阳离子-π等相互作用而在主-客体化学、超分子化学及仿生研究中备受青睐.已有多个研究组从事该类化合物的设计、合成、分子识别、仿生及超分子性能研究.我们已研究了烷基、芳基、甾体、葡萄糖类等咪唑鎓型环番[1-5].在此我们报道多羟基新咪唑鎓型环番.羟基的引入可使咪唑鎓型环番发挥氢键、偶极-偶极等非共价键力相互作用,增强咪唑鎓环番对阴离子、中性分子特别是DNA等生物分子的识别作用.  相似文献   

3.
新型手性咪唑鎓环番的合成及对氨基酸的对映选择性识别   总被引:2,自引:0,他引:2  
以L-氨基酸为手性源, 合成了一系列新型手性咪唑鎓环番, 并进行了结构表征. 在碱性条件下, L氨基酸和乙二醛、甲醛缩合生成了(S)-2-(1-咪唑)羧酸钠, 转化为甲酯后与乙二胺进行胺解反应制得开链手性咪唑二酰胺, 然后与二溴化合物在高稀淡技术和无水条件下进行季铵化关环反应, 再进行阴离子交换制得目标分子(4~6). 以手性咪唑鎓环番为主体分子, 研究了对氨基酸及其衍生物的对映选择性识别作用.  相似文献   

4.
白光发射超分子水凝胶的构筑和发光性能研究   总被引:1,自引:0,他引:1  
张依  陈湧  李晶晶  梁璐  刘育 《化学学报》2018,76(8):622-626
具有白光发射性质且发光可调的超分子水凝胶在发光材料和荧光检测领域具有广泛的应用前景.采用双(2-氨基丙基醚)聚丙二醇(PPG-NH2)链穿线带有正电荷的6-乙二胺修饰β-环糊精构成准轮烷,进而与锂皂石作用构筑了超分子水凝胶,并通过流变、zeta电势和扫描电镜等手段对凝胶性质进行了表征.当将扭曲分子内电荷转移(TICT)型的有机染料分子硫黄素T(ThT)和碘化4-[4-(二甲基氨基)苯乙烯基]-1-甲基吡啶鎓(DASPI)引入到水凝胶中,这两种有机染料能够在凝胶相中发生荧光共振能量转移(FRET),从而产生包括白光在内的不同颜色的荧光发射.本研究为水基超分子发光软材料提供了一种新的构筑方法.  相似文献   

5.
设计合成了以卟啉为分子“探针”的咪唑修饰的卟啉类化合物4和5. 通过对核磁共振氢谱、紫外-可见光谱及荧光发射光谱的研究显示, 化合物5通过卟啉环中心的锌及2个咪唑环上的活性氢与卤素离子形成三点键合超分子络合物, 并能选择性识别氟离子和氯离子(键合常数分别为5.95×104和7.17×104 mol-1·L).  相似文献   

6.
以1,3-双(2,6-二异丙基苯基)咪唑鎓盐酸盐(IPrHCl, 4a)或1,3-双[2,6-二(1-乙基丙基)苯基]咪唑鎓盐酸盐(IPent·HCl, 5a),及Grubbs 第一代催化剂和2-异丙氧基苯乙烯为原料,经去质子化反应和烯烃复分解反应合成了两种新型的NHC-钌催化剂4c和5c,其结构经1H NMR, 13C NMR和HR-MS(ESI)表征。并研究了4c和5c的性能。结果表明:4c和5c的稳定性较好,对关环复分解反应有良好的催化活性。  相似文献   

7.
温志勇  黄焰根 《合成化学》2011,19(6):694-698
含氟聚醚链修饰的咪唑与碘代烷烃经季铵化反应高产率地制备了4个新型的含氟聚醚链修饰的咪唑碘盐(3a ~3d);通过3的复分解反应合成了一系列新型的含氟聚醚链修饰的咪唑离子液体盐(4a ~4d,5a~5d),其结构经1 H NMR,19F NMR,IR和元素分析确证.热重分析研究表明,4和5具有较高的热稳定性.  相似文献   

8.
孙川  李睿  王文娟  冯燕 《合成化学》2019,27(9):717-722
以9,10-菲醌为原料,通过Debus-Radziszewski反应合成新化合物2-[1-(4-碘苯基)-1H-菲并咪唑基]苯酚(2);再通过Heck反应引入4-乙烯基吡啶合成了一种新的菲并咪唑衍生物2-[1-(4-乙烯基吡啶基苯基)-1H-菲并咪唑基]苯酚(3),其结构经1H NMR、 13C NMR、 HR-MS (ESI)和元素分析表征。通过紫外-可见吸收光谱和荧光发射光谱研究了其光学性质。结果表明:3在水中具有明显的聚集诱导发光性质,在含水量为90%的DMF/H2O溶剂中,荧光强度增强了6倍。3在DMSO-H2O混合溶剂中具有类似的AIE现象,含水量为70%时荧光强度最大。此外,3的细胞毒性小,生物成像实验表明:3可有效应用于细胞成像。  相似文献   

9.
采用改进的固相Wittig反应, 合成了一种新型的具有电子给受体和π共轭结构的咪唑衍生物1-{反式4-[4-(-N,N-二乙基氨基)苯乙烯基]苯}咪唑(C21H23N3, 简作L). 室温下, 将L与Co(SCN)2在甲醇中反应, 合成了配合物Co(SCN)2(C21H23N3)4. X射线单晶衍射分析结果表明, 该晶体属于三斜晶系, P1空间群, 晶胞参数a=0.931 7(3) nm, b=1.275 3(4) nm, c=1.669 1(5) nm, α= 89.521(5)°, β=84.591(5)°, γ=80.052(5)°, V=1.944 6(11) nm3, Z=1, μ=0.329 mm-1, Dc=1.234 Mg/m3, F(000)=765, R1=0.060 1, wR=0.138 1, GOF=1.030, 中心原子Co(Ⅱ)的配位数为6, 分别与来自4个L的咪唑N及2个SCN-的N配位, 形成八面体的空间构型. 配合物分子通过非典型氢键和π-π堆积作用形成三维超分子结构. 研究结果表明, 配合物具有很好的光学性质.  相似文献   

10.
聚集诱导发光(AIE)材料在生物医学领域有很大优势,尤其为生物成像研究开启了新局面.通过2,4,5-三苯基咪唑衍生物与1,4-二溴丁烷/1-溴丁烷亲核取代反应,合成了2个丁烷桥联的双咪唑衍生物及2个1-位丁基取代的单咪唑衍生物. 4个产物都表现出优异的AIE性质,其中含有甲氧基助色团的衍生物具有更长的发射波长.机理研究表明限制扭曲的分子内电荷转移是这类结构具有AIE活性的原因,因此, 2-位强吸电子芳基是它们具有AIE活性的决定因素.此外,咪唑环1-位取代基的空间效应对AIE也非常重要,因为较大体积的1-位取代基使分子呈扭曲构象,从而限制聚集态π-π堆积作用.最后,研究了1-位丁基取代的单咪唑衍生物的细胞染色和成像性能,结果显示二者在蓝色、绿色及红色通道都表现出不错的荧光成像能力,但在不同颜色通道观察到的细胞被染色区域不完全相同.  相似文献   

11.
多环芳二酐型聚酯亚胺膜的透气性能李悦生,丁孟贤,徐纪平(浙江大学高分子科学与工程研究所,杭州,310027)(中国科学院长春应用化学研究所)关键词聚醚酰亚胺,聚酯酰亚胺,膜,透气性通常的聚酰亚胺加工性能较差,在芳环二酐的苯环间引入醚键等柔性基团后,其...  相似文献   

12.
13.
微量元素与疾病诊断治疗的研究现状及展望   总被引:8,自引:0,他引:8  
对国内外微量元素与疾病的关系及其诊断治疗的研究现状及研究动向进行了综述,包括:微量元素与地方病、癌肿、心血管病、糖尿病、眼病、神经系统病等。参考文献72篇。  相似文献   

14.
A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg?1, the maximum residue level of European Union for quizalofop-p-ethyl).  相似文献   

15.
Herein, we present the synthetic route and the photophysical, electrochemical as well as laser properties of novel red‐emitting boron‐dipyrromethenes (BODIPYs) bearing arylethyne moieties. Such functionality is added along the main axis of the chromophore leading to single‐ and double‐substituted derivatives. The relationship between the dye structure and the lasing properties is studied in detail with the help of the photophysical and electrochemical properties as well as quantum mechanical simulations. The asymmetric substitution of the parent dye induces inhomogeneities in the charge distribution, which leads to an overall loss of the fluorescence capacity, mainly in polar media. Such non‐radiative deactivation processes can be softened by decreasing the electron‐donor ability of the substituent or even avoided by symmetrical substitution. Thus, grafting of the arylethyne moieties at the longitudinal axis of the indacene core results in an effective strategy to develop red‐edge BODIPYs with highly efficient and photostable laser emission.  相似文献   

16.
朱劲波  马立群  梁飞  苗迎春  王立民 《应用化学》2015,32(11):1221-1230
Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB5型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。  相似文献   

17.
钒与糖代谢及糖尿病   总被引:1,自引:0,他引:1  
微量元素钒作为生物体内必需元素,经证实有很重要的生理学功能,与机体糖代谢有十分密切的关系,且能降低糖尿病动物模型的高血糖,极有可能被开发为治疗糖尿病的药物。  相似文献   

18.
The monomeric ν(N—H) vibrations of various trisubstituted ureas of the R2UPh type and -thioureas of the R2TUPh type have been studied. The trans—out isomerism in the former and the trans—out—cis isomerism in the latter are discussed from the point of view of steric effect. The monomeric ν(N—H) vibrations of RPhUPh and RPhTUPh are also examined. The single band appearing in the spectrum of both ureas is characteristic of the cis form; this suggests the existence of phenyl—phenyl interaction (the stacking interaction proposed by Galabov et al. [10]). Behavior of ν(N—H) vibrations at several concentrations is shown to be clearly different in the three forms (trans, out and cis). The presence of the cis form is confirmed by solvent effect experiments.  相似文献   

19.
Tyrosol (T) and hydroxytyrosol (HOT) and their glycosides are promising candidates for applications in functional food products or in complementary therapy. A series of phenylethanoid glycofuranosides (PEGFs) were synthesized to compare some of their biochemical and biological activities with T and HOT. The optimization of glycosylation promoted by environmentally benign basic zinc carbonate was performed to prepare HOT α-L-arabino-, β-D-apio-, and β-D-ribofuranosides. T and HOT β-D-fructofuranosides, prepared by enzymatic transfructosylation of T and HOT, were also included in the comparative study. The antioxidant capacity and DNA-protective potential of T, HOT, and PEGFs on plasmid DNA were determined using cell-free assays. The DNA-damaging potential of the studied compounds for human hepatoma HepG2 cells and their DNA-protective potential on HepG2 cells against hydrogen peroxide were evaluated using the comet assay. Experiments revealed a spectrum of different activities of the studied compounds. HOT and HOT β-D-fructofuranoside appear to be the best-performing scavengers and protectants of plasmid DNA and HepG2 cells. T and T β-D-fructofuranoside display almost zero or low scavenging/antioxidant activity and protective effects on plasmid DNA or HepG2 cells. The results imply that especially HOT β-D-fructofuranoside and β-D-apiofuranoside could be considered as prospective molecules for the subsequent design of supplements with potential in food and health protection.  相似文献   

20.
In this work, ferrocene- and ferrocenium-containing salts were employed to modify montmorillonite. X-ray measurements show an increase in the interlayer spacing upon clay modification, which means that the larger and more organophilic cations were inserted into the gallery space of montmorillonite. Attempts to prepare nanocomposites of polystyrene and ethylene vinyl acetate copolymers lead to immiscible systems; the morphology of these systems was elucidated with TEM, XRD and cone calorimetry. The thermal stability of the composites is greater than that of the virgin polymer.  相似文献   

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