微波法合成反—丁烯二酸二甲酯

微波法合成反—丁烯二酸二甲酯刘福安，李耀光，徐文国，宋艳秋（吉林大学化学系长春１３００２３）关键词微波辐射，酯化反应，反—丁烯二酸二甲酯，合成反—丁烯二酸二甲酯是一种新型食品防腐剂，具有低毒、高效、广谱抗菌的特点，对霉菌且有特殊抑制作用，其性能优于丙...     

基于C—H键官能团化的药物合成

过渡金属催化的C—H键官能团化是有机化学的重要研究内容,并被作为工具广泛应用于药物合成领域。本文阐述了C—H键官能团化的经典反应类型,着重综述了C—H键的芳基化、烯基化、烷基化、卤化、羟基化、胺化和C—H插入反应在药物合成中的应用,详细描述了具体药物的合成实例,并对重要的反应机理进行了分析,最后展望了C—H键官能团化在药物合成中的发展前景。     

MCM—41型含V分子筛的合成与表征

本文合成出具有ＭＣＭ—４１型结构的含Ｖ和Ｖ—Ｔｉ分子筛，骨架红外、顺磁共振、紫外漫反射、固体魔角核磷、拉曼光谱、电子能借等测试结果表明Ｖ在分子筛中主要以分散的不流动的Ｖ￣（４＋）离子形式四配位存在于骨架上，Ｔｉ的存在不排斥Ｖ的同时进入骨架；同时考察了合成条件，吸附性能和热稳定性能。     

二吡啶四硝基酞菁钴的合成及光谱—电化学性质研究

本文报道了以钼酸铵为催化剂,将4—硝基邻苯二甲酸酐、脲和氯化铵混合,于220℃加热合成四硝基酞菁钴,将此配合物溶于吡啶,于115℃加热反应6天合成了二吡啶四硝基酞菁钻配合物。并对二吡啶四硝基酞菁钴的氧化还原半波电势、电解氧化还原产物的电子吸收光谱进行了研究。     

1─芳氧基乙酰基─4─苯甲酰氨基硫脲衍生物的合成及其生物活性研究

１─芳氧基乙酰基─４─苯甲酰氨基硫脲衍生物的合成及其生物活性研究魏太保，陈继畴（西北师范大学化学系，兰州，７３００７０）杨素铀，王秀春（西北师范大学生物系，兰州，７３００７０）关键词：１—芳氧基乙酰基—４—苯甲酰基氨基硫脲，相转移催化，合成，生物活性...     

（E,E）—2,8—二甲基—5—异丙烯基—2,8—癸二烯—1,10—二醇的新合成路线

β—榄香烯(2)是一种重要单环倍半萜化合物,存在于多种精油中,对它的化学性质、结构和生物活性进行了研究,标题化合物(1)是合成(2)的关键中间体,Vig等人曾以(E)—2—甲基—2—庚烯—6—酮酸乙酯的乙二醇缩酮为原料,通过七步反应合成了1。但步骤     

N—N键合成方法的研究进展

N—N键广泛存在于药物、天然产物和有机功能材料中,如何高效构建N—N键是有机合成的一个重要研究方向.基于含氨基、氰基、硝基和叠氮基等含氮基团的有机化合物非常多,直接利用这些含氮基团进行N—N键偶联为合成含N—N键结构单元的有机化合物提供了新的策略.综述了近年来发展的分子间和分子内构建N—N键的合成方法,并且对该方法存在的难点以及未来发展方向进行了展望.     

香草醛—N—酰腙类化合物的合成与表征

Ｓｃｈｉｆｆ碱类化合物和酰腙类化合物大多具有除草,杀菌等生物活性,已有一些报道［１,２］,对该类化合物的深入研究是当今农药界热点之一,表明此类化合物具有广阔的开发前景。据文献报道［１］,香草醛与芳胺反应生成的Ｓｃｈｉｆｆ碱类化合物具有优异的促进植物生根性。为寻求新的具有生物活性的物质,我们采用香草醛与酰肼反应,合成了３种未见报道的酰腙类化合物。其结构经ＩＲ,１ＨＮＭＲ和元素分析证实。合成反应如下：３—ＣＨ３Ｏ—４—ＨＯＣ６Ｈ３ＣＨＯ＋Ｈ２ＮＮＨＣＯ—Ｒ３—ＣＨ３Ｏ—４—ＨＯＣ６Ｈ３ＣＨＮＮＨＣＯ…     

应用Arndt-Eistert反应合成手性非天然N-Fmoc-β-氨基酸（Ⅲ）

以重氮甲烷为重氮化试剂，以非天然N—Fmoc—α—氨基酸为原料，成功地运用Amdt—Eistert反应，通过两步反应，高效快捷地合成了8个对应的同系物N—Fmoc—β—氨基酸。     

聚甲基丙烯酸4［（4’－烷氧酰基—1’—疏酰基苯）－1－羟乙氧基苯基］酯的合成

聚甲基丙烯酸４［（４’－烷氧酰基—１’—疏酰基苯）－１－羟乙氧基苯基］酯的合成张维邦，蒋，许家瑞，曾汉民（中山大学材料科学研究所广州５１０２７５）关键词侧链液晶高分子，含硫液晶单元液晶的合成侧链高分子液晶是高分子学科中非常活跃的研究领域“’，其特点是...     

Synthesis and characterization of nitric oxide-releasing sol-gel microarrays

Diazeniumdiolate-modified sol-gel microarrays capable of releasing low levels of nitric oxide are reported as a viable means for improving the blood compatibility of a surface without fully modifying the underlying substrate. Several parameters are characterized including: (1) NO surface flux as a function of sol-gel composition and microarray geometry; (2) microstructure dimensions and spacing for optimal blood compatibility; and (3) the effect of sol-gel surface modification on analyte accessibility to platinum electrodes. The sol-gel microarrays release biologically relevant levels of NO under physiological conditions for >24 h. In vitro platelet adhesion assays indicate that a NO surface flux of 2.2 pmol cm(-2) s(-1) effectively reduces platelet adhesion to glass substrates modified with sol-gel microstructures separated by 50 microm. The blood compatibility observed for these micropatterned surfaces is comparable to NO-releasing sol-gel films. When the separation between NO-releasing microstructures is reduced to 10 microm, the NO surface flux required to reduce platelet adhesion is lowered to 0.4 pmol cm(-2) s(-1). Finally, the oxygen response of platinum electrodes modified with NO-releasing sol-gel microarrays indicates that selective modification via micropatterning enhances analyte accessibility to the sensor surface.     

聚氧乙烯功能基复合修饰聚氨酯的合成及其血液相容性研究 (Ⅰ)──聚氨酯-接枝-十八烷基聚氧乙烯

通过十八烷基聚氧乙烯和环氧氯丙烷的封端反应制备了α-环氧基-ω-十八烷基聚氧乙烯大单体.并采用BF₃·Et₂O引发THF和大单体共聚合,得到了梳状的十八烷基聚氧乙烯接枝共聚醚.以该共聚醚为软段合成了十八烷基和聚氧乙烯复合修饰的聚氨酯(PEU-g-PEO-C₁₈).通过血小板粘附试验对材料的体外抗凝血性实验结果表明,采用具有选择性吸附白蛋白功能的十八烷基和PEO复合修饰聚氨酯,材料表面血小板粘附量明显减少.材料血液相容性的改善可能来源于疏水性的十八烷基和亲水性聚氧乙烯的协同作用.     

Synthesis and biocompatibility of phosphoryl polymer and relationship between biocompatibility and water structure

A series of copolymers, poly(methylmethacrylate-co-2-methacryloyloxyethyl phosphorylcholine), with various compositions of methyl methacrylate (MMA) and 2-methacryloyloxyethyl phosphorylcholine (MPC) were synthesized by radical copolymerization in a mixed solvent of ethanol and chloroform. The structures of the copolymers were confirmed by proton nuclear magnetic resonance and elemental analysis. The properties and morphologies of the copolymers were characterized by differential scanning calorimeter, scanning electron microscopy, and optical microscope. The adsorption of bovine serum albumin (BSA) and the adhesion of platelet on the surfaces of the copolymer membrane significantly decreased with increasing the MPC composition. The copolymers containing MPC above 18% showed excellent biocompatibility. Moreover, the relationship between the water structure and the biocompatibility was illustrated by changing quantity of the MPC in copolymers. The result showed that the amount of free water affected the platelet compatibility of the copolymer.     

Synthesis and evaluation of poly(hexamethylene-urethane) and PEG-poly(hexamethylene-urethane) and their cholesteryl oleyl carbonate composites for human blood biocompatibility

Two new urethane-based acrylates (UAA and PEG-UAA) were synthesized as polymer blocks. The chemical composition of the two monomers was confirmed by IR and NMR. After cross-linking these blockers by radical polymerization, "hexamethylene PU" [poly(hexamethylene-urethane)] and "PEG-hexamethylene PU" [PEG-poly(hexa-methylene-urethane)] were obtained. The platelet adhesion and platelet activation of these polymers were evaluated in the presence of Platelet Rich Plasma (PRP) blood. The relative blood clotting indexes of the polymers were determined to measure their capability of reducing thrombogenicity. The hemolysis of red blood cells was also assessed to examine the haemocompatibility of the polymers. The hexamethylene PU and PEG-hexamethylene PU showed less platelet adhesion, platelet activation, blood clotting and hemolysis than a commercial PU (Tecoflex). The liquid crystal molecule, cholesteryl oleyl carbonate (COC), showed further improved biocompatibility to human blood, after COC was embedded in the PU polymers. PEG-hexamethylene PU + 10% COC demonstrated the best activity in reducing thrombogenicity and the best haemocompatibility. The inclusion of PEG segments into the PEG-UAA structure increased its hydrophilicity. The methylene bis(cyclohexyl) segments in Tecoflex PU decreased haemocompatibility. These observations are in good agreement with performed contact angle measurements. The PEG-hexamethylene PU loaded with COC might be a promising material for applications in bioengineering.     

Inhibitory effect of hydrophilic polymer brushes on surface-induced platelet activation and adhesion

Poly(N,N-dimethylacrylamide) (PDMA) brushes are successfully grown from unplasticized poly(vinyl chloride) (uPVC) by well-controlled surface-initiated atom transfer radical polymerization (SI-ATRP). Molecular weights of the grafted PDMA brushes vary from ≈ 35,000 to 2,170000 Da, while the graft density ranges from 0.08 to 1.13 chains · nm(-2). The polydispersity of the grafted PDMA brushes is controlled within 1.20 to 1.80. Platelet activation (expression of CD62) and adhesion studies reveal that the graft densities of the PDMA brushes play an important role in controlling interfacial properties. PDMA brushes with graft densities between 0.35 and 0.50 chains · nm(-2) induce a significantly reduced platelet activation compared to unmodified uPVC. Moreover, the surface adhesion of platelets on uPVC is significantly reduced by the densely grafted PDMA brushes. PDMA brushes that have high molecular weights lead to a relatively lower platelet activation compared to low-molecular-weight brushes. However, the graft density of the brush is more important than molecular weight in controlling platelet interactions with PVC. PDMA brushes do not produce any significant platelet consumption in platelet rich plasma. Up to a seven-fold decrease in the number of platelets adhered on high graft density brushes is observed compared to the bare PVC surface. Unlike the bare PVC, platelets do not form pseudopodes or change morphology on PDMA brush-coated surfaces.     

聚氧乙烯功能基复合修饰聚氨酯合成及其血液相容性研究 (Ⅱ)──聚氨酯-接枝-聚氧乙烯氨基酸衍生物

采用以磺酸基为末端基的聚氧乙烯(PEO)接枝聚醚氨酯和氨基酸反应,将赖氨酸(Lys)和酪氨酸(Tyr)通过PEO为"间隔臂"固定在聚醚氨酯上,制备了氨基酸和PEO复合修饰的聚醚氨酯PEU-g-PEO-SO₂Lys和PEU-g-PEO-SO₂Tyr.通过血小板粘附试验对材料的体外抗凝血性进行了初步评价.研究结果表明,采用具有选择性吸附纤溶酶原功能的赖氨酸和PEO复合修饰聚氨酯,不仅减少了材料表面血小板粘附量,而且减少了材料表面血栓的形成量.     

A Commercial Nonbinding Surface Effectively Reduces Fibrinogen Adsorption but Does Not Prevent Platelet Adhesion to Fibrinogen

A commercial nonbinding surface effectively prevents protein adsorption; however, the platelet phenotype on this surface has yet to be defined. This study evaluates platelet adhesion and adsorption of several plasma/extracellular matrix (ECM) proteins to the nonbinding surface compared to other commonly used nontreated and high-binding surfaces. Platelet adhesion to uncoated microplates and those coated with fibrinogen or collagen is quantified by colorimetric assay. The binding capacity of the examined surfaces for plasma/ECM proteins is evaluated by measuring the relative and absolute protein adsorption. Compared to other surfaces, the nonbinding surface effectively prevents platelet adsorption, i.e. by 61-93% (Enzyme-Linked Immunosorbent Assay, ELISA), and reduces platelet adhesion, i.e. by 92%, when not coated with any protein. The nonbinding surface also decreases platelet deposition on collagen (up to 31%), but not fibrinogen. The nonbinding surface seems to be more of a low-fouling than nonfouling material, as it is able to reduce fibrinogen adsorption but not prevent platelet adhesion to fibrinogen. This feature should be considered when using the nonbinding surface for in vitro platelet testing.     

GRGDS修饰D,L-丙交酯-β-苹果酸共聚物的生物相容性研究

聚(D,L-丙交酯-β-苹果酸)(P-COOH)进行改性制得GRGDS修饰聚合物(P-GS5),利用红外光谱、元素分析和X射线光电子能谱确定了材料的结构和组成.通过内皮细胞粘附实验发现P-GS5可明显提高内皮细胞粘附(PDLLA,45%;P-GS5,109%),改善材料的细胞亲和性;同时血小板粘附实验结果也表明P-GS5可有效抑制血小板粘附(PDLLA,47%;P-GS5,18%),降低血栓形成的几率.     

Platelet adhesion and protein adsorption on silicone rubber surface by ozone-induced grafted polymerization with carboxybetaine monomer

Platelet adhesion and protein adsorption on the silicone rubber film grafted with N,N'-dimethyl-N-methacryloyloxyethyl-N-(2-carboxyethyl) ammonium (DMMCA) was studied. The grafting was carried out by means of ozone-induced method and was confirmed by ATR-FTIR and XPS investigations. The grafted films possessed relatively hydrophilic surface revealed by contact angle measurement. The blood compatibility of the grafted film was evaluated in vitro by platelet adhesion in platelet-rich plasma (PRP) and protein absorption in bovine fibrinogen (BFG) using silicone film as the reference. No substantial platelet adhesion was observed for the grafted films incubated in PRP for 60 and 180 min. The protein absorption was also significantly reduced after incubated in bovine fibrinogen for 60 min. Both the results indicated that the blood compatibility of silicone rubber was greatly improved by ozone-induced grafting of carboxybetaine zwitterionic polymer onto its surface.     

Modulation of hemocompatibility of polysulfone by polyelectrolyte multilayer films

Polyelectrolyte multilayer (PEM) films have been recently applied to surface modification of biomaterials. Cellular interactions with PEM films consisted of weak polyelectrolytes are greatly affected by the conditions of polyelectrolyte deposition, such as pH of polyelectrolyte solution. Previous studies indicated that the adhesion of several types of mammalian cells to PAH/PAA multilayer films was hindered by low pH and high layer numbers. The objective of this study is to evaluate whether the hemocompatibility of polysulfone can be modulated by deposition of poly(allylamine hydrochloride) (PAH)/poly(acrylic acid) (PAA) multilayer films. PAH/PAA multilayer films with different layer numbers were assembled onto polysulfone at either pH 2.0 or pH 6.5. The number of platelet adhesion and the morphology of adherent platelets were determined to evaluate hemocompatibility of modified substrates. Compared to non-treat polysulfone, the PEM films developed at pH 2.0 decreased platelet adhesion, while those built at pH 6.5 enhanced platelet deposition. Platelet adhesion was found positively correlated to polyclonal antibodies binding to surface-bound fibrinogen. The extent of platelet spreading was increased with layer numbers of PEM films, suggesting that the adherent platelets on thick PEM films were prone to activation. In conclusion, PAH/PAA films with few layers developed at pH 2.0 possessed better hemocompatibility compared to other substrates.