Cesium hydroxide-catalyzed hydrothiolation of alkynyl selenides to highly stereo- and regioselectively synthesize(Z)- -organoseleno-2-arylthio-1-alkenes

In the presence of catalytic amount of cesium hydroxide the hydrothiolation of alkynyl selenides occurred at room temperature in DMF under nitrogen atmosphere to give exclusive(Z)-1-organoseleno-2-arylthio-1-alkene in excellent yields.It could provide a new and expedient way for the preparation of(Z)-1-arylseleno-2-arylthio-1-alkene.     

新型4-N-(二茂铁亚甲基)-6-甲硫基-3-乙基-3-己醇手性配体的合成

以L-甲硫氨酸为手性源,经酯化、缩合、还原氨化及格氏试剂反应,设计并合成了一种新型的含硫二茂铁基的β-氨基醇手性配体--4-N-(二茂铁亚甲基)-6-甲硫基-3-乙基-3-己醇,其结构经<'1>H NMR,<'13>C NMR,IR及HR-MS表征.     

Optimal pinning synchronization on directed complex network

In this paper, pinning synchronization on directed network was considered. By analyzing, some general synchronization criteria on directed network were established. And then, we verified it on directed globally coupled network, directed scale-free network, and directed small-world network, respectively. The pinning nodes were selected, respectively, according to order of in-degrees and out-degrees. Through comparing and analyzing simulations, the optimal pinning scheme was found, and a practical principle was induced finally.     

催化动力学光度法测定合金中的镍

在(CH2)6N4HCl缓冲溶液中,OP乳化剂的存在下,痕量镍(Ⅱ)对H2O2氧化若丹明B(RhB)的褪色反应有强的催化作用,催化程度与镍(Ⅱ)量线性相关。基于此,建立了一种测定镍(Ⅱ)的分光光度法。结果表明,有色溶液的最大吸收波长为550nm,方法的检出限为04μg·L-1,催化程度与Ni(Ⅱ)量在0～030mg·L-1范围内符合比耳定律,选择性较好,可用于测定非晶态FeNiCr合金中的镍。     

质谱分析福尔马林固定组织的多肽谱

福尔马林固定组织时,甲醛与蛋白质多肽链的氨基酸侧链上的功能基团,特别是氨基、亚氨基、酰氨基、羟基和巯基等相结合,使蛋白分子间形成大分子网络,蛋白不再发生迁移达到固定目的[1].     

Density Functional Study of Small Neutral and Charged Silver Cluster Hydrides.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.     

Effect of Ligustri Lucidi Fructus on myelosuppression in mice induced by cytoxan

In this study, we aimed to demonstrate the therapeutic effect of Ligustri Lucidi Fructus on chemotherapy-induced myelosuppression and elucidate its mechanism. A pharmacological study was conducted to investigate the mechanism of the inhibiting effects of Ligustri Lucidi Fructus on cyclophosphamide-induced bone marrow suppression in mice. HPLC was used to measure the chemical components. We demonstrated that medium and high doses of Ligustri Lucidi Fructus increased the amount of white blood cells and bone marrow nucleated cells (p < 0.05) in the cyclophosphamian-induced mouse model, and at the same time reduced granulocyte–macrophage–colony stimulating factor and thrombopoietin in the serum of myelosuppression mice (p < 0.01). Medium and high doses of Ligustri Lucidi Fructus can also adjust the thymus index and spleen index(p < 0.05). Ligustri Lucidi Fructus regulates the balance of bcl-2/bax, inhibits the expression of Caspase-3 and meanwhile stimulates the expression of mitogen-activated protein (MEK) and phospho extracellular regulated protein kinases (p-ERK) on the MAPK pathway. Five chemical constituents of Ligustri Lucidi Fructus, which may be related to myelosuppression, were analyzed. The content of specnuezhenide was 0.281%, that of ligustroflavone was 0.004%, that of salidroside was 0.094%, that of hydroxytyrosol was 0.060% and that of tyrosol was 0.069%. The effect of Ligustri Lucidi Fructus on myelosuppression after chemotherapy may be related to its multicomponent and multitarget nature. Ligustri Lucidi Fructus may be a promising potential drug for treatment after chemotherapy.