气相色谱-质谱联用分析2-氯-5-三氯甲基吡啶

2-氯-5-三氯甲基吡啶是重要的农药中间体.采用气相色谱-质谱联用法,对高效除草剂盖草能的中间体2-氯-5-三氯甲基吡啶的分析条件进行了探讨和优化.使用Rts-5MS毛细管柱,EI电离源,实验结果的线性关系良好,相关系数r=0.9921,回收率为99.05%,相对标准偏差为0.78%.     

反式-2-取代硫代氨基脲基-4-芳基-5,5-二甲基-2-氧-1,3,2-二氧磷杂环己烷的立体选择性合成及立体化学研究

首先合成了重要的磷酰异硫氰酸酯中间体3, 然后便捷、高产率且立体选择性地合成了反式-2-取代硫代氨基脲基取代的新型六元磷杂环, 其立体化学通过2D NOESY NMR确证. 所有合成的化合物均进行了元素分析和光谱表征, 其中目标产物的13C NMR表征为1,3,2-二氧磷杂环己烷衍生物的碳骨架表征提供了难得的依据. 在溶剂DMSO-d6中, 所有产物均异构化, 生成磷原子的差向异构体. 这一研究结果证明了C4—H 以及31P NMR谱图与立体结构的相关性.     

Kinetics of formation of a linear polymer-polymer network system in the presence of 3d metal chelates

For semi-interpenetrating polymer networks (semi-IPNs) based on an incompatible polyurethane network/linear polymethylmethacrylate pair formed in situ in the presence of 3d metal chelates, we have studied the effect of the system composition on the kinetics of formation of the components and the nature of complex formation between the metal compound and the polymer matrix. The ratio of the system components has been shown to have an effect on the selection of the macroligand in formation of complexes of the metal chelate with the polar groups of the semi-IPN, where the general character of the kinetic behavior for the formation of the network and the linear polymer is preserved. __________ Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 42, No. 6, pp. 351–356, November–December, 2006.     

A new biodegradable polydepsipeptide microsphere for application in drug delivery systems

A sequential polydepsipeptide containing a tripeptide sequence L-alanyl-Lalanyl-ethyl L-glutamyl and an-hydroxy acid L-lactic acid, poly(Ala-Ala-Glu(OEt)-Lac), was synthesized to prepare the microspherical particles by the solvent evaporation process. In this case, the solvents play the most important role for the preparation of polydepsipeptide microspheres and, as an example, when 200 mg of the polydepsipeptide dissolved in 10 ml of 98/2% chloroform/dichloroacetic acid mixture was stirred at 400 rpm and 30 C, the microspherical particles with mean diameter of 58m were formed after pouring into 200 ml of 1% (w/v) poly(vinyl alcohol) solution. 17-Estradiol was incorporated into the particles, and the resulting particles were found to contain 5 mg of drug per 25 mg of the particle. The in vivo release of drug from the microspherical formulation was evaluated by measuring the pharmacological influence on rat prostate. It was found that the sufficient amount of drug, keeping the effective pharmacological influence, is supplied during the first 12-week period, followed by an incomplete supplying of drug intil the implant is perfectly degraded in vivo in the 25th week from the start of implantation.     

Wittig-Olefinierung zu neuen donor- und akzeptor-substituierten 3-Vinylindolen: Optimierte Syntheseverfahren

Summary The optimized Wittig reaction of selectively functionalized 3-acylindoles yield new, and for Diels-Alder reactions highly reactive donor- and acceptor substituted 3-vinylindoles, respectively.

     

(2-甲基丙烯酰氧乙基)三甲基氯化铵-丙烯酰胺反相微乳液共聚合研究

采用SPAN-OP复合乳化剂和K_2S_2O_8-Na_2SO_3氧化还原引发剂,进行(2-甲基丙烯酰氧乙基)三甲基氯化铵-丙烯酰胺的反相微乳液共聚合。测得单体的竞聚率r_(DM·MC)=1.11±0.16,r_(AM)=0.53±0.08。在单体总浓度为20—40％(wt),引发剂浓度为0.01—0.05％,乳化剂浓度为10—18％,聚合温度为299K的条件下,得到共聚反应动力学方程:R_p=k[M]~(1.07)[I]~(0.52)[E]~(0.90),文中对上述结果做了解释。     

Impact of electron-electron interaction on the electron energy distribution function in molecular plasmas under rf field action

Calculations of the electron energy distribution and of relevant macroscopic quantities of collision-dominated, weakly ionized plasmas under rf field action have been performed with increasing degrees of ionization, and the impact of the electron-electron interaction on these quantities was determined. The investigations were performed for the gas plasmas in CO and H₂ as representatives of molecular plasmas The energy distribution and macroscopic quantities are obtained by solving the nonstationary Bolizmann equation for a given rf field and degree of ionization taking into accoung and additional Fokker-Planck term besides the collision integrals for the elastic and the main inelastic collision processes. In these molecular plasmas a remarkable impact of the electron-electron interaction connected with increasing Maxwellization is observed for degrees of ionization greater than 10.     

环己硅烷类液晶化合物的量子化学研究

运用AM1和PM3两种SCF-MO方法，通过能量梯度全优化计算，给出20种环己硅烷类（苯基乙烷系）液晶化合物的稳定几何构型、电子结构和基本性质．联系有机电子结构理论进行了细致的讨论．     

Ni,Pd／Al2O3对丙酮加氢一步合成甲基异丁基酮性能比较

研究了Ａｌ２Ｏ３负载Ｎｉ、Ｐｄ催化剂上丙酮加氢一步合成甲基异丁基酮的反应活性。考察了不同Ｎｉ含量和不同Ｐｄ含量对活性的影响。结果表明，在载体Ａｌ２Ｏ３中加入不同含量的ＳｉＯ２后，会改善载体的性能，Ｎｉ／Ａｌ２Ｏ３催化剂中添加稀土元素Ｌａ或Ｃｅ后可改善催化剂的稳定性。