Synthesis,crystal feature and spectral characterization of paeonol derived Schiff base ligands and their Cu(II) complexes with antimicrobial activity

Four novel Schiff bases PNL-4OMe, PNL-4Br, PNL-4F, PNL-3,4-F₂, and their copper(II) complex with [M(L)₂(H₂O)₂] arrangement was synthesized using Paeonol and various aromatic substituted amines. Characterization has been done through FT-IR, ESI Mass, TG-DTA, DFT, magnetic measurements, elemental analysis, and Thermogravimetric analysis. Paeonol derived new bond formation in Schiff bases and changes in frequencies during complexation have been confirmed through FT-IR spectra. All complexes are thermally stable, paramagnetic, and have non-electrolytic behavior. The antimicrobial activity was also tested against Gram-positive bacteria; S. aureus, B. subtilis, and Gram-negative bacteria; E. coli, P. aeruginosa. Single-crystal X-ray data provide evidence that PNL-3,4-F₂ is recrystallizing in a triclinic system with P-1(2) space group and confirms the intramolecular H-bonding and short Vander Waal type interactions. Non-covalent interactions and π … π stacking surface interactions in PNL-3,4-F₂ were studied with Hirshfeld analysis. H-atoms have the highest interactions with other atoms of neighbouring molecules compared to all other atoms. DFT calculations were performed on the electronic structure of ligand PNL-3,4-F₂ and its copper(II) complex and discussed.     

有机催化靛红衍生酮亚胺与噁唑酮的不对称Mannich型加成反应

研究了手性磷酸催化的靛红衍生酮亚胺与噁唑酮的不对称Mannich型加成反应, 以良好至优秀的收率(高达97%)、 对映选择性(高达99% e.e.)以及非对映选择性(均>20∶1 d.r.)得到一系列含噁唑酮骨架的手性3,3′-二取代氧化吲哚化合物. 该反应可以进行扩大化和衍生反应.     

傅里叶思想的精髓及其伟大之处

介绍了傅里叶级数和傅里叶变换的基本思想,从哲学、物理学和数学的角度阐述了其深刻涵义和伟大之处.指出了傅里叶的思想和牛顿-莱布尼茨的思想的不同之处.导出了四维协变的傅里叶变换公式.简要介绍了傅里叶级数和变换在物理学中的应用.     

含(4,4′-二氟苯)甲酮肟醚官能团的1,2,3-三氮唑衍生物的合成及抗菌活性研究

以(4,4′-二氟苯)甲酮、盐酸羟胺、苄溴及溴丙炔为原料,应用5 mol%的CuI为催化剂,DMF-H 2O(1∶1)为溶剂,在70℃反应4h以23~81%的收率制得了9个含有(4,4′-二氟苯)甲酮肟醚官能团的1,2,3-三氮唑衍生物5(a~i)。合成的9个目标化合物通过熔点测定和质谱、红外光谱、核磁共振氢谱分析对其结构进行确证。经体外抗菌活性测试表明有4个化合物对时对所测试的大肠杆菌具有明显的抑制活性,其MIC为32ug·mL^-1。     

基于二噻吩并[2,3-b:3′,2′-d]噻吩开环反应的二芘基四联噻吩的制备及其激基缔合物荧光行为

通过芘基锂对二(三甲基硅基)二噻吩并[2,3-b:3′,2′-d]噻吩开环产生碳负离子,再经氯化铜氧化偶联,获得二芘基四联噻吩化合物.考察了该化合物在溶液中的光谱行为,结果表明,该化合物在溶液相的部分分子可以发生基于分子构象折叠而形成的分子内激基缔合物;在THF-H2O二元体系中可以形成分子间的基于激基缔合物的聚集诱导发光现象.     

3,3′-(1,1′-二苯基-4,4′-二基)-二丙烯酸的合成新方法

通过Heck反应,以4,4′-二碘联苯和丙烯酸为原料,壳聚糖负载钯为催化剂,合成了3,3′-(1,1′-二苯基-4,4′-二基)-二丙烯酸.考察了反应温度、时间、原料配比等因素对产率的影响.结果表明最佳反应条件为:反应温度为100℃,时间为20h,原料配比为1∶3.测试了壳聚糖负载钯催化剂的重复使用性能,并用IR、1 H NMR和MS对产物进行了表征.     

阿尔兹海默症血清多肽组生物标志物研究

采用个体样品单独分析的方式分析, 比较9个健康对照者、10个阿尔兹海默症(Alzheimer′s disease, AD)患者和12个认知功能障碍(Mild cognitive impairment, MCI)患者的血清多肽组分析结果, 以寻找潜在的AD病生物标志物.结果表明, 高强度的α-2-巨球蛋白肽段VGFYESDVMGR与AD病晚期阶段密切相关, 而载脂蛋白 C-Ⅲ、组蛋白H1.2和组蛋白H1.4的大量降解, 则与中早期AD和认知功能障碍相关联;载脂蛋白 C-Ⅲ和组蛋白H1的降解肽段具有明显的阶梯序列特征, 但在不同样本中的分布具有一定偶然性.AD病发展的晚期与中早期的血清多肽组特征不同, 这4种蛋白质的降解有可能成为AD病潜在的生物标志物.研究结果也证明了, 归属于纤维蛋白原α链、胸腺素β-4和斑联蛋白等蛋白质的肽段是所有血清样本中的优势肽段.本研究提出了利用血清多肽组学方法辅助诊断AD病的方法, 为临床大规模验证提供了依据和参考.     

Selective and direct detection of free amino acid using the optical birefringent patterns of confined nematic liquid crystals

Detection of amino acid (AA) is an essential step to understand various biological processes. In this study, we used innovative optical birefringent patterns of nematic liquid crystals (LCs) for the detection of several AAs. We attempted to use capillary-confined nematic LCs as sensor for AA analysis because their three-dimensional micro-scale architecture of LCs allowed better performance than that of mainly reported LC thin film sensors owing to the effect on the formation and dynamics of point defect. The sensing system was built by disrupting the alignment of a nematic LC, 4-cyano-4′-pentylbiphenyl (5CB), using the dopant of dodecyl aldehyde. Detection principle is based on the chemical analytical method of aldehyde titration for AAs, wherein the reaction between AAs and aldehyde group generates Schiff bases that could alter the configuration of nematic LCs at the aqueous/LC interface. The patterns generated in the reaction are captured by polarising optical microscopy (POM) and are visible to the naked eye. The functionalised LCs detected glycine at concentrations as low as 1 pM. There was a surprising result that it can selectively detect D-AAs against their L-isomers, however, further efforts are required to explain the mechanism.     

新型N-芳基哌嗪取代苯并呋喃衍生物的合成

以5-二甲氨基水杨醛和2-溴-4'-氟苯乙酮为原料,经缩合和取代反应制得中间体6-二乙氨基-2-[4'-(N-哌嗪基)苯甲酰基]苯并呋喃(2);2与卤代烃反应合成了6个新型的N-芳基哌嗪取代苯并呋喃衍生物(4a~4f),收率76%~93%,其结构经1H NMR,13C NMR和HR-MS(ESI-TOF)表征。     

Electrochemical Detection of Para‐nitrophenol using Copper Metal Nanoparticles Modified Gold Electrode

para‐Nitrophenol (p‐NP) is a high priority environmental pollutant. For the sake of safety, sensitive detection of its presence in water resources and food is highly important. The present article describes the use of copper metal nanoparticles for selective and sensitive electrochemical detection of p‐NP in pure and real sample. For this the gold electrode was fabricated by polyvenylpyrrolidone stabilized copper metal nanoparticles (ca . 4 nm d.) via self‐assembled 4,4′‐bipyridine monolayer and characterized by microscopic and electrochemical techniques. The newly developed sensor permits for sensitive detection of p‐NP in a linear concentration range of 1–500 μM with lowest detection limit of 0.34 nM and high sensitivities 247.1 μA cm⁻² μM⁻¹. The sensor electrode exhibited high stability, reproducibility, good selectivity in the presence of potential interfering agents and had an excellent capability for the selective determination of p‐NP in river water without preliminary treatments.