Diarylheptanoids from the root bark of Juglans cathayensis

A new diarylheptanoid glucoside,（8R,9R）-17-methoxy-2-oxatricyclo[13.2.2.1^3.7]icosa-l（17）,3（20）,4,6, 15,18-hexaene-4,9,10-triol-9-O-β-D-glucopyranoside（1）,namely jugcathayenoside,together with two known diarylheptanoids,（+）-galeon（2） and 4-hydroxy-17-methoxy-2-oxatricyclo[13.2.2.1^3,7 ]icosa-1（17）,3（20）,4,6,15,18-hexaene-9-one（3）,were isolated from the root bark of Juglans cathayensis. Their structures were elucidated on the basis of extensive spectroscopic data analysis.     

Highly Enantioselective Ring‐Opening Reactions of Aziridines with Indole and Its Application in the Building of C3‐Halogenated Pyrroloindolines

A magnesium‐catalyzed asymmetric ring‐opening reaction of aziridine with indole has been realized by employing commercially available chiral ligands. Both of the enantiomers of the ring‐opening product could be obtained with good yields and a high level of enantioselectivity. The corresponding ring‐opening product could be further transformed to various types of enantioenriched C₃‐halogenated‐pyrroloindolines.     

太赫兹时域光谱技术在化学领域中应用的新进展

随着超快激光技术的发展及其人们对太赫兹(THz)电磁波波段及与脉冲光源认识的进一步深入,太赫兹时域光谱(THz-TDS)技术作为一种新的、快速发展的光谱分析方法在许多领域备受关注。尤其在化学领域,THz-TDS技术已得到了广泛的应用,并显示出了广阔的应用前景。本文介绍了THz技术的特点、THz辐射的产生、探测及其信号处理;讨论了该技术在化学及其相关领域中的应用;初步探讨了该技术在化学领域应用中一些亟待解决的问题及今后发展的方向。     

有序介孔有机金属 Pd(II) 的制备及其催化水介质中的 Suzuki 反应

 以有机金属 Pd 硅烷和乙基桥联硅烷为混合硅源, 在表面活性剂作用下进行共缩聚反应, 制备了有序介孔有机金属 Pd(II) 催化剂 Pd(II)-PMO(Et). 采用傅里叶变换红外光谱、核磁共振谱、X 射线衍射、透射电子显微镜和 N2 吸附脱附等手段对催化剂进行了表征. 结果表明, 与后嫁接法相比, 共聚法制得的催化剂活性位分散均匀, 孔道不易堵塞, 同时乙基修饰的孔壁增强了催化剂表面疏水性, 有利于反应物在孔道内的扩散和吸附. 在水介质 Suzuki 反应中, Pd(II)-PMO(Et) 的催化活性与均相催化剂 Pd(PPh3)2Cl2 的相当, 且可重复使用.     

Double Modification of Electrode Surface for the Selective Detection of Epinephrine and Its Application to Flow Injection Amperometric Analysis

A glassy carbon electrode having two polymer layers has been applied to selectively detect epinephrine. The inner layer formed by electropolymerization of macrocyclic nickel complex functioned as an electrocatalyst for epinephrine oxidation and the outer layer composed of hydrolyzed polyurethane γ‐benzyl L ‐glutamate as a screening layer. Differential pulse voltammetry showed almost 100% recovery of epinephrine even in 100‐fold excess of interferents. When applied to a dual glassy carbon electrode as an amperometric detector in flow injection analysis, a linear response over 0.1 μM and 10 μM was obtained. Recovery tested for 5‐fold diluted human urine samples was 97.5%.     

五种中药中微量元素及重金属元素的含量分析

用微波消解-原子吸收分光光度法对巴戟天、大黄、陈皮、板蓝根、茯苓等5种中药材中的7种金属微量元素进行了含量分析。结果表明,该法的线性良好,重现性在3.3%~11%之间,精密度在2.6%以内,回收率满足定量分析要求;5种药材中铅均未超标,茯苓中镉超出国家标准;5种药材里的铜含量均有超标,其中,巴戟天超标最严重;铁在5种药材中的含量最高,其中以巴戟天含量最为丰富,达到了746.750 mg/kg,其次是锌和锰,铬的含量最少。结论:对5种药材中铜均出现超标,虽然在边缘位置,但应该予以重视;巴戟天中丰富的铁元素,可能在防止癌变发生和发展中起到一定功效。     

Preparation of magnetic polylactic acid microspheres and investigation of its releasing property for loading curcumin

In order to obtain a targeting drug carrier system, magnetic polylactic acid (PLA) microspheres loading curcumin were synthesized by the classical oil-in-water emulsion solvent-evaporation method. In the Fourier transform infrared spectra of microspheres, the present functional groups of PLA were all kept invariably. The morphology and size distribution of magnetic microspheres were observed with scanning electron microscopy and dynamic light scattering, respectively. The results showed that the microspheres were regularly spherical and the surface was smooth with a diameter of 0.55-0.75 μm. Magnetic Fe₃O₄ was loaded in PLA microspheres and the content of magnetic particles was 12 wt% through thermogravimetric analysis. The magnetic property of prepared microspheres was measured by vibrating sample magnetometer. The results showed that the magnetic microspheres exhibited typical superparamagnetic behavior and the saturated magnetization was 14.38 emu/g. Through analysis of differential scanning calorimetry, the curcumin was in an amorphous state in the magnetic microspheres. The drug loading, encapsulation efficiency and releasing properties of curcumin in vitro were also investigated by ultraviolet-visible spectrum analysis. The results showed that the drug loading and encapsulation efficiency were 8.0% and 24.2%, respectively. And curcumin was obviously slowly released because the cumulative release percentage of magnetic microspheres in the phosphate buffer (pH=7.4) solution was only 49.01% in 72 h, and the basic release of curcumin finished in 120 h.