N,N-二乙基二硫代氨基甲酸钠与不同桥连的半胱氨酸钼络合物的配位体交换反应

双-μ-氧代-(1),μ-氧代-μ-硫代-(2),双-μ-硫代一双(半胱氨酸钼)(3)和N,N-二乙基二硫代氨基甲酸钠能进行配位体交换反应,由于不同原子所成桥的稳定性不同,生成了不同的产物。     

Reaction of Aromatic and Unsaturated Compounds with the Potassium Permanganate/HCl (HBr) Acetonitrile Reagent

Addition of hydrochloric or hydrobromic acid to a solution of potassium permanganate in acetonitrile produced a homogeneous mixture, which is suitable for laboratory chlorination or bromination, respectively. Aromatic compounds more reactive than alkylbenzenes can be chlorinated or brominated without additional catalyst. Alkenes and alkynes give the corresponding vicinal dihaloalkanes and vinyl halides. All reactions complete within two hours under mild condition (25-60 °C) with excellent to moderate yields.     

高效凝胶过滤色谱法分离测定豆薯种子蛋白

用高效凝胶蛋白往分离豆薯种子蛋白租提液,结合光电二极管阵列检测器对分离的蛋白峰进行紫外光谱扫描来确认蛋白的纯度,测定了3种蛋白的分子量,采用邻苯二甲醛（OPA）柱后衍生法测定了豆薯种子蛋白的氨基酸含量。     

低分子量壳聚糖及其水溶性衍生物对质粒DNA和mRNA的影响

研究了低分子量壳聚糖及其O-羧甲基壳聚糖和O-羟乙基壳聚糖在不同质量分数和作用时间下,对大肠杆菌质粒DNA(pBR322和pUC18)的体外结合能力。研究结果表明,原料壳聚糖对2种质粒都有较强而稳定的结合能力;其2种衍生物对质粒的作用效果受空间位阻效应和氨基基团数量的共同影响,在适当的质量分数(≥1×10-2)和相对分子质量(2000,5000,8000及以上)的条件下,对质粒DNA都具有很强的结合能力。研究表明,壳聚糖及其衍生物对DNA的结合是基于正负电荷的静电吸引作用,结合过程短暂,结合能力不受作用时间的影响。相对分子质量为3000～5000的原料壳聚糖和O-羧甲基壳聚糖均可以有效阻碍mRNA的复制,且O-羧甲基壳聚糖在同等条件下影响作用较大,推测是由于此种衍生物对氨基的质子化能力较大和体积庞大造成。大肠杆菌体内转化实验表明,壳聚糖和O-羧甲基壳聚糖不仅可以和DNA结合而使之不能转化,而且可以直接阻碍正常质粒DNA向大肠杆菌的转化过程。     

合成3,3''''-二吲哚基苯基甲烷的新方法

以无水乙醚为溶剂,室温下无水三氯化铝催化N-(2-氯乙基)苯甲醛亚胺与吲哚反应,合成了3,3'-二吲哚基苯基甲烷和6,12-二苯基吲哚[2,3-b]咔唑,其结构经1H NMR,IR和MS表征.     

疏水改性MCM-41对甲草胺缓释性能的影响

采用浸渍法将甲草胺吸附到纯硅MCM-41(M41)介孔材料中, 以六甲基二硅氮烷(HMDS)为表面改性剂, 通过气-固反应对吸附了甲草胺的M41材料(Ach/M41)进行疏水改性, 得到了既具有高载药性又能有效延缓甲草胺释放的缓释体系Ach/TMS-M41. XRD、低温N₂吸附/脱附、FT-IR和TG等分析结果表明, 甲草胺在M41中的吸附量高达0.381 g·g^-1(质量分数为27.6%), 此时M41仍保持原有的孔道结构, 且甲草胺能完全分散于M41孔道中. 分别对Ach/M41和Ach/TMS-M41在水中的缓释性能进行了测试, 甲草胺释放率分别为62%和38.1%, 表明疏水改性对延缓甲草胺释放有较好的效果. 而且, 介孔材料孔壁对甲草胺具有明显的紫外屏蔽保护作用.     

A facile, microwave-assisted, palladium-catalyzed arylation of acetone

We report an expedient method for the heteroarylation of acetone under tin-free conditions. The coupling is performed using the commercially available enol silane of acetone (2-trimethylsilyloxypropene) and a corresponding aryl bromide, chloride or triflate under microwave-assisted conditions, with tris(dibenzylideneacetone)dipalladium (Pd₂(dba)₃) or palladium acetate (Pd(OAc)₂) and 2-(2′,6′-dimethoxybiphenyl)dicyclohexylphosphine (S-Phos) as the catalyst system.     

Effect of Transition Metals (Cu, Co and Fe) on the Autothermal Reforming of Methane over Ni/Ce0.2Zr0.1Al0.7Oδ Catalyst

The transition metals (Cu, Co, and Fe) were applied to modify Ni/Ce0.2Zr0.1Al0.7Oδ catalyst.The effects of transition metals on the catalytic properties of Ni/Ce0.2Zr0.1Al0.7Oδ autothermal reforming of methane were investigated. The Ni-supported catalysts were characterized by XRD, TPR and XPS.Tests in autothermal reforming of methane to hydrogen showed that the addition of transition metals (Cu and Co) significantly increased the activity of catalyst under the conditions of lower reaction temperature,and Ni/Cu0.05Ce0.2Zr0.1Al0.65Oδ was found to have the highest conversion of CH4 among all catalysts in the operation temperatures ranging from 923 K to 1023 K. TPR, XRD and XPS measurements indicated that the cubic phases of CexZr1-xO2 solid solution were formed in the preparation process of catalysts.Strong interaction was found to exist between NiO and CexZr1-xO2 solid solution. The addition of Cu improved the dispersion of NiO, inhibited the formation of NiAl2O4, and thus significantly promoted the activity of the catalyst Ni/Cu0.05Ce0.2Zr0.1Al0.65Oδ.     

共轭亚麻酸的制备、表征和生物活性研究进展

近年来的研究发现共轭亚麻酸(CLN)具有多种非常有益的生理功能,已成为化学家、药理学家、营养学家争相研究的热点。本文就CLN的制备、表征、分离分析以及生物活性等方面,对国内外的研究进行了综述。CLN的制备包括化学法、生物法和天然产物提取法三大类。CLN的表征方法主要有紫外光谱、红外光谱、核磁共振等方法,以及采用气相色谱法(GC)、高效液相色谱法(HPLC)和毛细管电泳法(CE)等方法对合成的CLN混合物进行分离分析。CLN的生物活性主要有抗癌、降血脂、减肥、抗致癌等。     

葛根中葛根素的分离纯化技术进展

葛根素是葛根药材质量控制的主要指标。文章综述了近年来国内葛根提取物中葛根素的分离纯化技术进展。同时,指出β-环糊精键合固定相技术因具有绿色环保和低成本的优点,而成为发展的重点和方向。