大孔吸附树脂分离纯化杜仲中活性成分

比较了AB-8．NKA-9．NKA-11．D-140．D-101．HPD-600、S-8及聚酰胺等8种吸附树脂对杜仲中的活性成分京尼平甙和松脂醇二葡萄糖甙的吸附及脱附性能．在静态吸附研究的基础上，筛选出效果较好的树脂进行动态实验研究．实验表明：最佳的同时分离纯化松脂醇二葡萄糖甙和京尼平甙的树脂为S-8．并进行了该树脂对杜仲中两种活性成分的吸附和脱附研究，确定了最佳的工艺参数。     

由脂肪酸酯制备高碳醇Cu－Fe系催化剂的研究

由脂肪酸酯制备高碳醇Ｃｕ－Ｆｅ系催化剂的研究刘寿长②王文祥②陈诵英①（①中国科学院山西煤炭化学研究所，太原０３０００１）（②郑州大学化学系，郑州４５００５２）关键词高碳醇Ｃｕ－Ｆｅ系催化剂加氢反应高碳醇被广泛用于洗涤剂、增塑剂、合成纤维、表面活性剂、...     

改性阳离子树脂催化二氢月桂烯水合反应的研究

将R-H阳离子交换树脂与一些金属离子进行交换改性后，催化二氢月桂烯水合制取二氢月桂烯醇。并对催化剂的制备及性能、水合产物和反应条件进行了初步探讨。     

MAWLDI质谱检测蛋白质与富勒醇的非共价复合物

基质辅助激光解吸电离质谱由于受到酸性基质，样品制备，激光诱导聚合和基质加合物的形成等条件的限制而难以用于非共价复合物的检测。本文以芥子酸为基质，观察到蛋白质与富勒醇的特殊相互作用，一些质谱特征，如质量数迁移，宽的加合峰和定量结合比表明，在蛋白质和富勒醇之间形成了特殊的非共价复合物。     

乳液聚合法制备聚合物与十二醇复合乳胶粒

通过乳液聚合法, 以苯乙烯、丙烯酸丁酯为主要单体, 以甲基丙烯酸为功能性单体, 以二乙烯基苯或二甲基丙烯酸乙二醇酯为交联剂, 制备了包覆有十二醇的聚合物复合颗粒. 通过动态光散射粒径仪和透射电镜观测乳胶粒粒径和形态, 气相色谱法测试了十二醇的包覆率, 并探讨了聚合过程中十二醇包覆率的变化情况. 结果表明十二醇的包覆率和十二醇与单体的质量比及单体转化率显著相关, 并且在聚合过程中包覆率存在先升后降的趋势. 实验发现十二醇包覆率的先升后降是由聚合物和十二醇的相容性不好引起的.     

吸附树脂法在泽泻提取物的脱色及高纯度泽泻醇制备中的应用研究

将具有脱色和吸附双重功能的新型吸附树脂用于泽泻提取物的脱色和高纯度泽泻醇提取物的制备工艺中,考察了树脂结构对脱色性能和吸附性能的影响熹见律.结果表明,兼具适宜的比表面积和功能基含量的No.2树脂具有最佳的纯化效果,只通过"吸附-解吸"一步工艺,产品纯度即可从1.93%提高到50%以上,泽泻醇的回收率高于95%.初步探讨了树脂的吸附机理,认为树脂对泽泻醇的吸附是单纯的疏水性作用力,而对色素的吸附应为疏水-离子交换双重作用的协同效应.     

集成原位生长和界面聚合法制备聚酰胺/ZIF-8反渗透膜

制备同时具有高通量和高选择性的新型反渗透膜是近年来的研究重点与难点之一。针对芳香族聚酰胺反渗透膜的低渗透性,本文基于ZIF-8型金属-有机骨架材料的纳米级多孔结构,制备了新型聚酰胺/ZIF-8反渗透膜。首先,通过原位生长法在聚砜超滤底膜表面多次生长ZIF-8,然后,由两步界面聚合法在长有ZIF-8的底膜上制备无缺陷的聚酰胺皮层。通过以不同浓度的苯酚水溶液为分离体系探究反渗透分离性能,发现本工作制备的新型聚酰胺/ZIF-8膜的渗透通量较聚酰胺膜提高了57%以上,且截留率无明显降低。本文提出的制膜方法集成了原位生长和界面聚合两种方法,简便可行,可实现制备性能优异的新型反渗透膜。     

聚合醇在钻井液中的应用研究进展

聚合醇对油气层的伤害性小,具有抑制性强,润滑性好,荧光级别低,不干扰录井,可生物降解,毒性低、价格低廉等优点,被应用于国内外油田钻井作业中。本文综述了国内外对聚合醇在抑制性、润滑性、流型调节三个方面研究进展,以抑制性为主,重点阐述了聚合醇抑制机理学说:浊点理论、渗透理论和吸附理论,三种学说很好的论证了聚合醇的抑制性能,但是都存在一定的局限性。针对现场应用出现的问题,介绍了近些年聚合醇在疏水改性、纳米材料改性、离子液改性几个方面的研究现状,其抑制性与稳定性都得到了提升。同时也对聚合醇今后的发展走向及应用前景进行了展望。     

甲基丙烯酸缩乙二醇双酯、甲基丙烯酸三羟甲基丙烷三酯的制备

甲基丙烯酸缩乙二醇双酯(简称双酯)、甲基丙烯酸三羟甲基丙烷三酯(简称三羟三酯)是常用的烯类聚合交链剂,在制备感光树脂板、厌氧粘合剂、齿科用复合充填树脂等方面已获得广泛应用。双酯、三羟三酯的制备方法分直接酯化和酯交换两种。直接酯化是甲基丙烯酸与相应的醇在硫酸、苯     

部分醇解聚乙烯醇接枝聚对二氧环己酮的合成与表征

制备了部分醇解的PVA(paPVA),将其与PDO在均相本体接枝聚合,通过对paPVA醇解度以及投料比的选择,得到了具有各种分子结构的接枝共聚物.通过一维核磁共振谱表征了聚合物的微观结构;采用TG、DSC等测试手段研究了接枝共聚物的热性能和结晶性能.     

Glass-state amorphous salt solids formed by freeze-drying of amines and hydroxy carboxylic acids: effect of hydrogen-bonding and electrostatic interactions

We studied effect of molecular interactions on the physical properties of binary freeze-dried solids and frozen aqueous solutions using model chemicals containing various functional groups (amino, carboxyl, hydroxyl). Thermal analysis of frozen solutions containing alkyl diamines and hydroxy di- or tricarboxylic acids showed thermal transitions (T(g)': glass transition of maximally freeze-concentrated phase) at temperatures higher than those of the individual solutes. A binary frozen solution containing 80 mM 1,3-diamino-2-hydroxypropane (single-solute T(g)'<-60 degrees C) and 120 mM citric acid (single-solute T(g)': -55.0 degrees C) made the transition at -30.8 degrees C. The molecular weight of the solutes had smaller effects on the transition temperatures of the frozen mixture component solutions. Lyophilization of some high T(g)' mixture frozen solutions (e.g., 1,3-diamino-2-hydroxypropane and citric acid) resulted in cake-structure amorphous solids with glass transition temperatures (T(g)) higher than those of the individual components. Networking of intense hydrogen-bondings and electrostatic interactions between the heterogeneous molecules through the multiple functional groups was suggested to reduce the component mobility in the amorphous freeze-concentrated phase and the freeze-dried solids. Controlling the interactions should be a key to optimizing the physical properties of multi-component amorphous freeze-dried pharmaceutical formulations.     

A tetradecanuclear copper dimeric macrocyclic complex with a body-centred heptanuclear core-structure and magnetism

2,6-Diformyl-4-methylphenol and 1,3-diamino-2-hydroxypropane template condense in the presence of Cu(NO(3))(2) and azide to produce a 3 : 3 macrocyclic ring containing an unprecedented grouping of seven copper(ii) ions within the macrocyclic cavity, with the seventh metal completing a body-centred heptanuclear lattice.     

Hydroboration-oxidation of ricinoleic acid derivatives

The regioselectivity in the hydroboration-oxidation of ricinoleic acid derivatives only slightly depends on the configuration of the optically active center: the fraction of the resulting 1,3-diol is larger by 6–10% than that of the 1,4-isomer. The new asymmetric center has preferentially S configuration, as follows from the formation of the corresponding stereoisomeric 1,3-dioxane from the 1,3-diol and of 2,5-dialkyltetrahydrofuran from the 1,4-diol.     

Synthesis of polyamide containing optically active thymine derivative as a grafted pendant

A new route to polyamides containing optically active thymine groups as pendants has been established. The method is based on the grafting of (–) and (±)-2-(thymin-1-yl)propionic acid [(–) and (±) TPA] onto a polyamide containing hydroxyl groups. The hydroxy polyamide was prepared by selective N-acylation of an active diester of N-hydroxy-5-norborene-2,3-dicarboxamide (HONB), N,N'-(isophthaloyl-dioxy)-bis(5-norbornene-2,3-dicarboximide) (IPBONB), with 1,3-diamino-2-hydroxypropane (AHP). Model compounds (?) and (±)-(1,3-dibenzoylamino-2-propyl)2-(thymin-1-yl)propionate[(?) and (±) (BAPTP)] were prepared by direct, low-temperature esterification before synthesizing the polymer.     

A radical-anion chain mechanism following dissociative electron transfer reduction of the model prostaglandin endoperoxide, 1,4-diphenyl-2,3-dioxabicyclo[2.2.1]heptane

The model prostaglandin endoperoxide, 1,4-diphenyl-2,3-dioxabicyclo[2.2.1]heptane (3), was investigated in N,N-dimethylformamide at a glassy carbon electrode using various electrochemical techniques. Reduction of 3 occurs by a concerted dissociative electron transfer (ET) mechanism. Electrolysis at -1.6 V yields 1,3-diphenyl-cyclopentane-cis-1,3-diol in 97% by a two-electron mechanism; however, in competition with the second ET from the electrode, the resulting distonic radical-anion intermediate undergoes a beta-scission fragmentation. The rate constant for the heterogeneous ET to the distonic radical-anion is estimated to occur on the order of 2 x 10(7) s(-1). In contrast, electrolyses conducted at potentials more negative than -2.1 V yield a mixture of primary and secondary electrolysis products including 1,3-diphenyl-cyclopentane-cis-1,3-diol, 1,3-diphenyl-1,3-propanedione, trans-chalcone and 1,3-diphenyl-1,3-hydroxypropane by a mechanism involving less than one electron equivalent. These observations are rationalized by a catalytic radical-anion chain mechanism, which is dependent on the electrode potential and the concentration of weak non-nucleophilic acid. A thermochemical cycle for calculating the driving force for beta-scission fragmentation from oxygen-centred biradicals and analogous distonic radical-anions is presented and the results of the calculations provide insight into the reactivity of prostaglandin endoperoxides.     

Structure of 1,3-Bis-(3-benzoxazolonyl)-2-hydroxypropane

We have studied the ¹H NMR spectrum of the synthesized 1,3-bis(3-benzoxazolonyl)-2-hydroxypropane. The nature of the splitting of the signals in the spectrum and computer modeling indicate that free rotation is possible about all non-ring bonds in the compounds.     

Hydroboration-oxidation of ricinoleic acid ester derivatives

The chiral center in ricinoleic acid methyl ester (ee ～100%) strongly affects the regioselectivity of its hydroboration-oxidation, so that the resulting 1,3-diol dominates by 74% over the 1,4-isomer. Furthermore, new asymmetric centers are formed preferentially with (S)-configuration, up to 87% for 1,3-diols and up to 100% for 1,4-diols.     

Elastomeric/antibacterial properties in novel random Ricinus communis based-copolyesters

Poly(ricinoleic acid) (PRA), coming from the self-polycondensation of ricinoleic acid (RA), which derives from castor oil, is a very interesting polymer because of its intrinsic antimicrobial activity. However, its mechanical properties are insufficient for whatever application, thus copolymerization is required. In this work, two polyesters based on 1,3 propanediol (PD), such as poly(propylene terephthalate) (PPT) and poly(propylene isophthalate) (PPI), were chosen to prepare random copolyesters containing ricinoleate units. Different content of RA have been tested, such as 10 and 25 mol% respect to the comonomer (terephthalic or isophthalic dimethylester), to evaluate the lowest composition able to confer antibacterial activity. The materials were tested against Staphylococcus aureus and Escherichia coli, and 25 mol% of RA unit resulted to impart antimicrobial activity. Furthermore, thermal properties (DSC and TGA) as well as the elastomeric response of films were investigated. The copolymer PPI/PRA containing 10 mol% of RA presents very high elongation at break, around 1300%. Therefore, by tuning the RA amount it is possible to obtain outstanding elastomeric or antibacterial materials, suitable for textiles and/or film engineering applications.     

An efficient synthesis of 1,3-bis(1,4,7-triazacyclonon-1-yl)-2-hydroxypropane, [1,3-bis(TACN)-2-propanol]

Abstract

An efficient synthesis of 1,3-bis(1,4,7-triazacyclonon-1-yl)-2-hydroxypropane is described. In contrast to earlier procedures, an improved synthetic strategy led to the selection of suitable reagents and conditions that afforded the title compound in excellent overall yield with improved process efficiency and scalability. Moreover, the mildness and synthetic efficiency of the chosen conditions were particularly well-suited for the large-scale synthesis of the title compound, which is in increasing demand for a variety of applications, including the preparation of stationary phases for immobilized metal-ion affinity chromatography of recombinant proteins.     

Synthesis and properties of polyaromatic dendrimers possessing a repetitive amide-ester coupling sequence

A series of novel polyaromatic dendrimers that feature tris-(2-ethylamino)amine as the central core unit has been synthesized up to the third generation by employing a convergent growth strategy. The building blocks 1,3-diamino-2-hydroxypropane and 4-carboxybenzaldehyde were used for dendron construction, a process that involved the cyclic repetition of esterification, oxidation and selective amidation steps. Molecular modelling of this class of dendrimers has been used to predict potential solution state conformations employing molecular mechanics and molecular dynamic simulations. In addition, the results of preliminary metal binding studies using the first generation dendritic system are also outlined.