9-咔唑-羧酸化合物的微波合成及其生物活性研究

9-咔唑 -羧酸化合物不但是医药[1] 、有机光导材料[2 ] 的中间体 ,而且其本身亦具有干扰素诱导能力[3] .近年来 ,我们[4 ] 应用 9-咔唑 -乙酸和丙酸作为高效液相色谱分析氨基酸、胺和醇类的衍生化试剂 .目前所合成的此类化合物很少 .近 1 5年以来 ,微波在有机合成中的应用已发展成为一个新的研究领域[5] ,许多反应已在微波炉中高产率快速地实现了 .本文采用微波辐照法快速合成了系列 9-咔唑 -羧酸化合物 3 a— 3 m,优化了反应条件 ,并测试了它们的生物活性 .反应式如下 :丷4R5丯HR3 R2R1( 1) +Br R6COOC2 H5( 2 ) 丷4R5丯R6COOHR3 R…     

Microwave spectroscopic and ab initio studies of pyrolysis products of 2-nitrosopropene (syn form) and its pyrolysis mechanism

The pyrolysis products of CH₂=C(CH₃)---NO (syn form) have been determined by microwave spectroscopy. The pyrolysis products of CH₂=C(CH₃)---NO (syn form) and its ¹⁵N isotopic species were found to be CH₂=O, CH₃CN, and CH₃C¹⁵N. The produce of formaldehyde and methyl cyanide suggests that the C=C and N=O double bonds of CH₂=C(CH₃)---N=O (syn form) were broken. To explain the generation of the two molecules, a four-membered ring molecule (9) as an intermediate, is proposed. The four-membered ring molecule as an intermediate is also supported by ab initio MO calculation. Applying the pyrolysis mechanism obtained for 2-nitrosopropene (syn form) to that of 1,1,2-trichloronitrosoethane, one of its complicated pyrolysis mechanisms was explained. The rotational constants and geometrical parameters of two intermediates, 9 and CH₂=CCl---NO (13), were obtained by ab initio MO calculation (MP2/6-31G**) to predict their microwave spectra.     

多功能微波等离子体化学反应装置及其应用

建立了一台多功能微波等离子体化学反应实验装置,可用于化学合成、表面处理、多相催化等多种研究,为新方法、新工艺、新思路的实现提供了实验基础。     

微波辅助提取-紫外分光光度法检测土壤中的油脂总量

以合成土样为对象 ,研究了微波辅助提取油脂的条件及其提取效率 ,由此建立了土壤中油脂分析的快速光度检测方法。在中档微波场辐射 3× 10 s时 ,2次 15 m L丙酮 -正己烷 (体积比 1∶ 1)萃取 10 g合成土样中的油脂时所获收率最高。方法的平均回收率大于 97.3% ,RSD小于 2 .5 % ,其结果与索氏萃取 4 h的效果相当     

微波辐射法合成4A沸石及表征

本文主要是采用微波辐照的方法合成4A沸石分子筛,并先后以纯化学原料,工业用高岭土为原料等进行合成,结果表明4A沸石合成的质量与微波功率及辐照时间密切相关,用高岭土为原料能合成出与化学法具有同等质量的4A沸石。     

微波消解/ICP-MS法测定中草药中痕量元素的研究

研究了微波消解 / ICP- MS测定中草药中痕量元素的新方法。方法的检出限为 0 .0 0 6—0 .0 37ng·m L-1;精密度为 0 .6 %— 4 .5% ;回收率为 88.2 %— 10 8%。该方法简单、快速、准确 ,结果令人满意。     

微波溶样-原子吸收法间接测定叶片中的叶绿素总量

以10mL 0.5mol/L盐酸为溶剂,微波溶解卟啉环中的镁离子,原子吸收法间接测定了植物叶片的叶绿素平均含量。方法的回收率为98.5%,RSD为2.46%。     

微波辐射下的1,4-二甲基咔唑-9-羧酸的快速合成

以ＤＭＦ为溶剂,在微波辐射下由１,４－二甲基咔唑和相应的溴酯快速合成了两种１,４－二甲基咔唑－９－羧酸化合物,在最佳反应条件下,产率分别为８５．２％和８３．１％。     

Zeolite HY and Silica Gel as New and Efficient Heterogenous Catalysts for the Synthesis of Triarylimidazoles under Microwave Irradiation

Summary.  Zeolite HY and silica gel efficiently catalyzed the three component condensation of benzil, benzaldehyde derivatives, and ammonium acetate under solvent-free conditions and microwave irradiation. Received February 22, 2000. Accepted (revised) March 22, 2000     

Microwave-assisted activation for electroless nickel plating on PMMA microspheres

A novel microwave-assisted activation method for electroless plating on PMMA microspheres is presented in this study. When the microwave irradiation was applied during the activation step, the amount of the Pd species adsorbed on PMMA surfaces was much higher than that of sample pretreated with a conventional activation process without microwave irradiation. With this activation method, it was also shown that the adsorbed Pd species with a size of 4-6 nm were uniformly distributed on the surfaces of the PMMA microspheres, thus a smooth and uniform nickel-phosphorus coating on the PMMA microspheres was obtained by subsequent electroless plating. The samples after each step were characterized by XPS, TEM, ICP and SEM.