Synthesis of 2-phenylbenzofuran derivatives and selective binding activities on estrogen receptor

An improved chemical reaction protocol with short time and easy work-up was described here for 2-phenylbenzofuran derivatives. The final purified products, 2-phenylbenzofuran derivatives 5a-g and the intermediate diols 4a-g, were evaluated for their estrogen receptor (ER) binding affinity and selective activity in vitro. Among these fourteen tested compounds, 4g and 5g showed higher binding affinity on ER subtypes, ERα and ERβ. Compound 4g exhibited preferable ERα binding, while 5g was more estrogen selective for ERβ. The molecular docking was also performed to explore the detailed interactive interface between ER and the compounds.     

Facile synthesis of 1-aminoisoquinolines via the tandem reactions of 2-alkynylbenzaldoximes with isothiocyanates

A new, concise, and efficient route for the synthesis of 1-aminoisoquinolines in good to excellent yields is described; this involves the reaction of 2-alkynylbenzaldoximes and isothiocyanates, which is catalyzed by silver triflate in dichloromethane, at room temperature. This transformation involves tandem 6-endo cyclization, [3+2] cycloaddition, and subsequent rearrangement. The simple operational protocol provides a cost-effective, diversity-oriented route to 1-aminoisoquinolines under neutral, mild conditions.     

Copper‐Catalyzed Direct C Arylation of Heterocycles with Aryl Bromides: Discovery of Fluorescent Core Frameworks

A window of opportunity : A general copper‐catalyzed C? H bond‐activation path allows arylation of heterocycles with a wide range of aryl bromides (see scheme). The reaction shows excellent regioselectivity and exhibits good functional group tolerance. The 8‐aryl xanthines exhibit fluorescence in a variety of solvents and show promise as reagents for biological imaging.

     

Enhanced electronic correlation and thermoelectric response by Cu-doping in Ca(3)Co(4)O(9) single crystals

The structure, anisotropic magnetic, electrical and thermal transport properties for single crystals of Ca(3)Co(4-x)Cu(x)O(9) (x = 0, 0.2, 0.4, 0.6 and 0.8) have been investigated systematically. The Cu-doping with x = 0.2 at Co-site is sufficient to drive the low-temperature spin-glass state in the Ca(3)Co(4)O(9) system. The value of resistivity along ab-plane decreases monotonously with increasing x in the whole temperature range studied, and around room temperature, the in-plane resistivity of Ca(3)Co(3.2)Cu(0.8)O(9) is about 71% smaller than that of the undoped sample. The temperature region where the Fermi-liquid transport mechanism dominates becomes remarkably narrowed due to the Cu-doping while the electronic correlation in the system is enhanced. With further addition of Cu in the Ca(3)Co(4)O(9) system, the in-plane thermopower (S(ab)) increases slowly and the room-temperature S(ab) for Ca(3)Co(3.2)Cu(0.8)O(9) is about 17% larger than that of the undoped sample. As a result, the power factor along the ab-plane is enhanced by about 3.8 times compared to the undoped sample. The results are suggested to originate from the variations of carrier concentration and electronic correlation in this system via the different Cu-doping states: Cu(3+)/Cu(2+) (Cu(3+) major) into the CoO(2) layer for x ≤ 0.4, while Cu(2+)/Cu(3+) (Cu(2+) major) into the Ca(2)CoO(3) layers for x > 0.4.     

Gas chromatography-mass spectrometry analysis of di-n-octyl disulfide in a straight oil metalworking fluid: application of differential permeation and Box-Cox transformation

The aim of this study was to identify and quantify an unknown peak in the chromatogram of a very complex mixture, a straight oil metalworking fluid (MWF). The fraction that permeated through a thin nitrile polymer membrane had less mineral oil background than the original MWF did at the retention time of the unknown peak, thus facilitating identification by total ion current (TIC) gas chromatography-mass spectrometry (GC-MS). The peak proved to be di-n-octyl disulfide (DOD) through retention time and mass spectral comparisons. Quantitation of DOD was by extracted ion chromatogram analysis of the DOD molecular ion (mass-to-charge ratio (m/z) 290), and of the m/z 71 ion for the internal standard, n-triacontane. Linear models of the area ratio (y) of these two ions versus DOD concentration showed a systematic negative bias at low concentrations, a common occurrence in analysis. The linear model of y(0.8) (from Box-Cox power transformation) versus DOD concentration showed negligible bias from the lowest measured standard of 1.51 mg/L to the highest concentration tested at 75.5 mg/L. The intercept did not differ statistically from zero. The concentration of DOD in the MWF was then calculated to be 0.398+/-0.034% (w/w) by the internal standard method, and 0.387+/-0.036% (w/w) by the method of standard additions. These two results were not significantly different at p < or = 0.05. The Box-Cox transformation is therefore recommended when the data for standards are non-linear.     

高活性单分散磺化聚苯乙烯多孔微球用于生物柴油制备研究

采用回流-沉淀聚合法高效制备了单分散交联多孔聚苯乙烯微球，再在温和的条件下对其进行磺化，制备了磺化聚苯乙烯多孔微球.以调控磺化度和酸密度为目标，重点考察了溶剂用量、溶胀时间、氯磺酸用量、磺化温度和磺化时间等影响因素.用5 mL CCl₄溶胀0.5 g交联聚苯乙烯微球，然后加入0.3 mL氯磺酸，在50℃磺化75 min，磺化度和酸密度分别可以达到85.1%和2.611 mmol·g^-1.该磺化聚苯乙烯微球在催化油酸和甲醇酯化合成生物柴油中表现出很高的催化活性，远高于酸性离子交换树脂Ameberlyst-15，接近于均相的浓硫酸体系；且循环使用3次后，催化活性仍可保持初始活性的92%.提供了一种简单、绿色和可控的方法，制备了酸密度可控、稳定性好的单分散磺化聚苯乙烯微球，在工业制备生物柴油领域具有较好的前景.     

在饮水中典型溶解性有机氮酪氨酸氯化生成氯仿的机理分析

饮用水氯化消毒可以有效杀灭细菌, 但同时会产生危害人体健康的消毒副产物(DBP). DBP生成机理研究是有效控制DBP的前提. 溶解性有机氮(DON)是DBP的重要前体物, 选取典型DON-丙氨酸(Ala)、苯丙氨酸(Phe)和酪氨酸(Tyr)作为氯仿(CF)等DBP的前体物, 研究三种氨基酸(AA)的耗氯量和CF产率; 同时考察了Tyr氯化中间产物2,4,6-TCP的氯化特性和CF产率; 采用GC/MS扫描和前线轨道理论验证, 探讨了CF的主要生成路径. 研究发现, 在同等氯化反应条件下, 由于侧链基团的不同, Tyr的耗氯量以及CF产率都明显高于Ala和Phe, 从而说明Tyr确实是一种重要的CF前体物质. CF的主要生成路径为Tyr→ 4-MCP → 2,4-DCP → 2,4,6-TCP → CF. 氯胺消毒工艺可有效控制CF的生成, 并能减少2,4,6-TCP的产生, 但不能确保饮用水的生物安全性. 氯化消毒之前将Tyr等重要前体物去除可能是控制CF等DBP更加有效的措施.     

Synthesis and antibacterial activity of four natural chalcones and their derivatives

Four natural chalcones bearing hydroxyisoprenyl or prenyl groups, named Paratocarpin E (2), Xanthoangelol D (3), Angusticornin A (4) and Kanzonol C (5), were prepared by employing the Claisen-Schmidt condensation as the key step. In an attempt to investigate the effect of the hydroxyisoprenyl group on biological activity, two of their derivatives were also prepared for antibacterial activity research. The synthesized compounds were investigated for their expected antibacterial activities against Gram positive bacteria (Bacillus subtilis, Staphylococcus aureus) as well as Gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa). Paratocarpin E (2) was found to be the most potent against two Gram positive bacteria while the majority of the remaining compounds showed promising activity as well. However, all of the compounds were inactive against both Gram-negative bacteria.     

Molecular dynamics simulation of AFM studies of a single polymer chain

Single polymer chain force-extension behavior measured by Atomic Force Microscopy (AFM) was interpreted by molecular dynamics (MD) simulation performed by applying a bead-spring (coarse-graining) model in which the bond potential function between adjacent beads is described by a worm-like chain (WLC) model. Simulation results indicate that caution should be applied when interpreting experimental AFM data, because the data vary depending on the point of AFM tip-polymer chain attachment. This approach offers an effective way for eventual analysis of the mechanical behavior of complex polymer networks.     

3333lp/mm X射线透射光栅的研制

针对X射线透射光栅摄谱仪中的高线密度光栅,研究了采用电子束曝光和X射线曝光技术结合制作高线密度X射线透射光栅的工艺技术.首先利用电子束曝光和微电镀技术在镂空的薄膜上制备母光栅X射线掩模版,然后利用X射线曝光和微电镀技术小批量复制光栅.在国内首次完成了3333lp/mm X射线透射光栅的研制,栅线宽度为150nm,周期为300nm,金吸收体厚度为500nm.衍射效率标定的结果表明,该光栅的占空比合理、侧壁陡直,具有良好的色散特性,能够满足空间探测、同步辐射和变等离子诊断等多个领域的应用.