硝基化合物还原、氢化的研究 Ⅳ.用Fe~(3+)催化转移氢化3,3′-二硝基-4,4′-二氨基二苯醚

以Fe~(3+)代替Pd-C和Raney Ni为催化剂、水合肼为供氢体、3,3′-二硝基-4,4′-二氨基二苯醚为受氢体、甲醇为溶剂,进行催化转移氢化反应,产物3,3′,4,4′-四氨基二苯醚(TADPO)质量好,得率可达80%。此外,还对反应温度、时间、以及水合肼、催化剂、溶剂用量,水合肼浓度、催化剂重复使用等影响因素进行了研究,获得了较佳工艺条件。本法制得的TADPO与均苯四甲酸二酐缩聚可制得性能良好的聚眯唑吡咙。     

缓和加氢裂化动力学模型

参考缓和加氢裂化（ＭＨＣ）反应机理，开发了一种既能预测产品产率，又能预测产品性质的ＭＨＣ动力学网络模型。以文献上发表的ＭＨＣ实验数据为例，进行了参数估计，确定了动力学参数，给出了模型的标准差。本模型所预测的ＭＨＣ结果，与文献数据吻合良好，具有良好的预测性能。     

吡喹酮杂质的研究

用LC-MS和HPLC法以对照品对照,确定吡喹酮合成过程中产生的主要杂质是(1,11b)-位不饱和的吡喹酮,利用催化氢化法可把含该杂质过量的吡喹酮粗品转化为合格品.     

化工工艺设计过程中几种决策方法的应用

催化裂化汽油通过加氢处理可有效降低硫含量,是清洁汽油或清洁汽油调和油生产的重要过程。随着环保标准的日益严格,汽油加氢技术的研发和使用正日益受到重视,在技术开发、工艺设计、项目投资的过程中要面临诸多决策问题,从管理学角度对不同级别决策问题适用的决策方法和模型进行了介绍,并对定量决策方法、定性决策方法以及定量与定性相结合的决策方法使用场合提出了一些建议。     

Plasma hydrogenated cationic detonation nanodiamonds efficiently deliver to human cells in culture functional siRNA targeting the Ewing sarcoma junction oncogene

The expression of a defective gene can lead to major cell dysfunctions among which cell proliferation and tumor formation. One promising therapeutic strategy consists in silencing the defective gene using small interfering RNA (siRNA). In previous publications we showed that diamond nanocrystals (ND) of primary size 35 nm, rendered cationic by polyethyleneimine-coating, can efficiently deliver siRNA into cell, which further block the expression of EWS/FLI-1 oncogene in a Ewing sarcoma disease model. However, a therapeutic application of such nanodiamonds requires their elimination by the organism, particularly in urine, which is impossible for 35 nm particles. Here, we report that hydrogenated cationic nanodiamonds of primary size 7 nm (ND-H) have also a high affinity for siRNA and are capable of delivering them in cells. With siRNA/ND-H complexes, we measured a high inhibition efficacy of EWS/FLI-1 gene expression in Ewing sarcoma cell line. Electron microscopy investigations showed ND-H in endocytosis compartments, and especially in macropinosomes from which they can escape before siRNA degradation occurred. In addition, the association of EWS/FLI-1 silencing by the siRNA/ND-H complex with a vincristine treatment yielded a potentiation of the toxic effect of this chemotherapeutic drug. Therefore ND-H appears as a promising delivery agent in anti-tumoral gene therapy.     

Effect of Modification of Amorphous Silica with Ammonium Agents on the Physicochemical Properties and Hydrogenation Activity of Ir/SiO2 Catalysts

The modification of commercial silica with solutions of NH₄F or NH₄Cl salts, followed by thermal treatment, enabled generation of the acidic sites in SiO₂ and changed its textural properties. The use of ammonium salts solution also caused the generation of additional porosity. Using NH₄F solution caused significant decrease in the specific surface area and the increase in the average pore diameter. The number and strength of resulting acid sites depend on the nature of anion in the applied ammonium salt and the concentration of salt solution. It has been found that the sample treated with NH₄F presented higher total acidity (TPD–NH₃) and the amount as well as the strength of acid sites increased with the concentration of the used modifier. As modified amorphous SiO₂ materials used as a support for iridium (1 wt %, Ir(acac)₃) nanoparticles permitted to obtain highly active catalysts for toluene hydrogenation under atmospheric pressure. The highest activity (expressed as the apparent rate and TOF) was obtained for iridium catalysts supported on silica modified by NH₄F with the highest acidity. The modification of silica with NH₄F favors the generation of centers able to adsorb toluene, which results in higher activity of this catalyst.     

Side reactions in peptide synthesis

During the hydrogenolytic removal of the benzyl ester from the pentapeptide Boc-Asp(OBzl)-Ala-Phe-Ile-Gly-OEt, either with hydrogen gas or ammonium formate in the presence of palladium-on-charcoal as catalyst, variable amounts (5–30%) of an unexpected by-product were always obtained. The compound was eventually identified as Boc-Asc-Ala-Phe-Ile-Gly-OEt (Asc = aminosuccinyl). The application of field desorption mass spectrometry as a diagnostic tool is reported. The study of this side reaction, carried out on the pentapeptide and two other dipeptide models, showed that: 1) palladium-on-charcoal may induce Asc formation; 2) the contemporary presence of the catalyst and a base (even in trace amounts) greatly increases the by-product formation; 3) the side reaction is sequence and solvent dependent; 4) the Asc formation is completely prevented by adding a few equivalents of acetic or formic acid. Some mechanistic considerations are also reported.     

煤加氢液化和苯加压萃取所得沥青质组成结构的研究

借助~1H-NMR、IR、分子量测定和元素分析,采用Brown-Ladner方法,研究了煤加氢沥青质(Ⅰ)和苯加压萃取沥青质(Ⅱ)的组成结构,计算了碳原子分布、芳香度、芳环和脂环数等结构参数,推测了它们的化学结构模型,并与煤的化学结构模型进行了比较。Ⅰ随反应温度增加,芳香度急剧提高。390℃、430℃和470℃时,其芳香度分别为0.78、0.85和0.91,说明在高温下发生了脱氢反应。Ⅱ的芳香度随煤的变质程度增加而提高,其组成结构与煤本体没有根本的差别,是分散在高分子结构中的低分子化合物。     

Isolation,identification, and characterization of a palladium complex in the catalytic deprotection of a protected peptide

The final catalytic deprotection in the large scale synthesis of thymopentin (Arg-Lys-Asp-Val-Tyr) produced an impurity which had not previously been observed. Isolation by preparative HPLC and spectroscopic characterization led to a postulated structure of the impurity as the 1: 1 thymopentin-palladium complex. A complex corresponding to the proposed structure was independently synthesized and shown to have identical chromatographic and spectroscopic properties with the isolated material. Proton and carbon (13) NMR were used to determine the coordination sites of the peptide with palladium. The susceptibility of the complex to hydrogenation indicated a possible source for its formation.     

3-氨甲基吡啶的合成工艺改进

报道了3-氨甲基吡啶的合成工艺改进，在常温、常压条件下，采用催化氢化的方法合成了3-氨甲基吡啶。该法易于工业化生产。