毛细管区带电泳法测定板蓝根注射液中四种核苷的含量

采用毛细管区带电泳法测定了板蓝根注射液中胞苷、腺苷、鸟苷和尿苷的含量。电泳条件:采用未涂层石英毛细管(32.5 cm×50 μm i.d.,有效长度23.5 cm),以60 mmol/L硼砂溶液-10%(体积分数)异丙醇-20%（体积分数）乙腈为运行缓冲液,在25 ℃下以20 kV恒压电泳分离,压力进样 (1 kPa×10 s),检测波长254 nm。对电泳条件各因素进行了讨论,如缓冲液的种类、浓度和pH值,有机改性剂的种类和浓度,分离电压和毛细管温度等。样品经0.45 μm微孔滤膜过滤后直接进样;采用外     

Synthesis of Novel Benzoylphenylurea Chitin Inhibitors From Chlorothalonil(Ⅱ)

IntroductionThe insecticidal activity of benzoylphenylurea( BPU ) analogues,discovered in the early1 970′s[1_ 4] ,is connected with the process ofmoult-ing and appears to affect the chitin synthesis of in-sects. The benzoylphenylurea class of insectgrowth regulators( IGRs) ,interfere with chitinsynthesis in target pests,causing death or abortivedevelopment and are considered to be the fourthgeneration of insecticides or novel materials for in-sect control.Benzoylphenylurea type insecticides…     

八棱丝瓜蛋白1的二级结构及其生物活性

测定了八棱丝瓜蛋白1的N端顺序为Asp-Val-Ser-Phe-Ser-,用CD谱测定了八棱丝瓜蛋白 1的α螺旋,β-折叠和无规卷曲含量分别为37.1%,33.4%,29.5%。实验表明,八棱丝瓜蛋白 1具有RNA N-糖苷酶活性,体外抑制肿瘤细胞生长活性表明其对肿瘤细胞株B16,MGC,Bel的半数抑制浓度分别为1.78×10-7mol/L,2.11×10-7mol/L和4.21×10-7mol/L。并在N端顺序,二级结构和生物活性方面对八棱丝瓜蛋白 1和天花粉蛋白进行了比较。     

工业丙烯腈中噁唑及其它有机杂质的气相色谱分析

提出了一种用毛细管气相色谱分析工业丙烯腈中微量噁唑及其它杂质的方法。用气相色谱．质谱法对丙烯腈中的噁唑及其它杂质进行了定性,并用化学法验证了噁唑的定性结果。采用有效碳数法计算出噁唑的质量相对校正因子为2．396,内标法测定了国内不同公司生产的丙烯腈中微量杂质的含量。其中噁唑的质量含量为0．001％-0．06％。方法已在某石化公司丙烯腈装置技术改造中应用于噁唑含量的控制分析。     

The Chemical Speciation and Behavior of Mercury and Selenium in the Insoluble Fraction of Striped Dolphin Liver

Most of the mercury and selenium exist in the insoluble fraction of dolphin liver. After the insoluble fraction was digested by alkaline protease in the presence of 1% SDS, approximately 50% of Hg and Se consisted in the supernatant and the others in the residue. Gel filtration chromatography of the hydrolysate showed that 96% of Hg and 87% of Se were combined with the high molecular weight proteins stably, which cannot be substituted by the complex reagents.Mercury and selenium in the residue were confirmed as HgSe crystal.     

Synthesis and Photochemical Properties of a New Substituted Phenol Covalently Linked to Ruthenium （Ⅱ） Tris-bipyridine Containing Four Ester Groups as Sensitizer

As photosensitizer for solar cell, a new ruthenium (Ⅱ) complex with four ester groups had been synthesized, in which a phenol substituted by {[(2-hydroxy-5-tert-butylbenzyl)(pyridyl-2-methyl)amino]methyl} is covalently linked to ruthenium (Ⅱ) tris-bipyridine. The structures of the new compounds were confirmed by NMR and ESI-MS spectra. The electrochemical and photochemical properties were also studied.     

Redox‐Neutral α‐Allylation of Amines by Combining Palladium Catalysis and Visible‐Light Photoredox Catalysis

An unprecedented α‐allylation of amines was achieved by combining palladium catalysis and visible‐light photoredox catalysis. In this dual catalysis process, the catalytic generation of allyl radical from the corresponding π‐allylpalladium intermediate was achieved without additional metal reducing reagents (redox‐neutral). Various allylation products of amines were obtained in high yields through radical cross‐coupling under mild reaction conditions. Moreover, the transformation was applied to the formal synthesis of 8‐oxoprotoberberine derivatives which show potential anticancer properties.     

Synergetic Spin Crossover and Fluorescence in One‐Dimensional Hybrid Complexes

Hybrid materials integrated with a variety of physical properties, such as spin crossover (SCO) and fluorescence, may show synergetic effects that find applications in many fields. Herein we demonstrate a promising post‐synthetic approach to achieve such materials by grafting fluorophores (1‐pyrenecarboxaldehyde and Rhodamine B) on one‐dimensional SCO Fe^II structures. The resulting hybrid materials display expected one‐step SCO behavior and fluorescent properties, in particular showing a coupling between the transition temperature of SCO and the temperature where the fluorescent intensity reverses. Consequently, synergetic effect between SCO and fluorescence is incorporated into materials despite different fluorophores. This study provides an effective strategy for the design and development of novel magnetic and optical materials.     

Spatial,Hysteretic, and Adaptive Host–Guest Chemistry in a Metal–Organic Framework with Open Watson–Crick Sites

Biological and artificial molecules and assemblies capable of supramolecular recognition, especially those with nucleobase pairing, usually rely on autonomous or collective binding to function. Advanced site‐specific recognition takes advantage of cooperative spatial effects, as in local folding in protein–DNA binding. Herein, we report a new nucleobase‐tagged metal–organic framework (MOF), namely ZnBTCA (BTC=benzene‐1,3,5‐tricarboxyl, A=adenine), in which the exposed Watson–Crick faces of adenine residues are immobilized periodically on the interior crystalline surface. Systematic control experiments demonstrated the cooperation of the open Watson–Crick sites and spatial effects within the nanopores, and thermodynamic and kinetic studies revealed a hysteretic host–guest interaction attributed to mild chemisorption. We further exploited this behavior for adenine–thymine binding within the constrained pores, and a globally adaptive response of the MOF host was observed.