1,6-二氢-S-四嗪催化重排及其反应的研究--Ⅱ. 与氯甲酸三氯甲酯反应

在4－二甲胺基吡啶的存在下，1，6－二氢－S－四嗪重排成3，6－二氢－S－四嗪，与双光气反应后再与不同的胺反应，合成了11种1，4－二取代产物，产物经元素分析、IR和^1H NMR确证。用UV和^1H NMR分析结果对反应机理进行了初步探讨。     

双齿单Schiff碱钴、锰配合物的合成、表征及催化氧化性能的研究

合成了单S chiff碱配体水杨醛缩邻甲苯胺（^1L）、5-溴水杨醛缩对氯苯胺（^2L）、5-溴水杨醛缩对甲苯胺（3^L）、水杨醛缩对硝基苯胺（^4L）、水杨醛缩对甲苯胺（^5L）、水杨醛缩对氯苯胺（^6L）及其钴、锰配合物，并用MS、^3HNMR、IR以及元素分析等测试技术予以表征，以钴配合物为催化剂活化分子氧氧化环巳烯，高选择性地得到烯丙位的氧化产物；以锰配合物为催化剂、NaOcl为氧化剂催化苯乙烯的环氧化，主要产物为苯乙烯环氧化物。     

3—二氯乙酰基—2，5—二甲基—2—乙基—1，3—E唑烷的一锅法合成与生物活性

利用“一锅法”合成了标题化合物，经元素分析，IR和^1H NMR确定了结构，并对产物进行了初步的生物活性测定。     

无溶剂微波促进下1－苯基－3－甲基－5－吡唑啉酮与芳酰氯的反应研究

无溶剂条件下，微波促进1－苯基－3－甲基－5－吡唑啉酮与等量的酰氯反应 ，可高产率简便得到5－酰化产物。在有氢氧化钙存在时与2倍量的酰氯反应主要得 到4，5－位酰化产物，产物结构经^1H NMR,^13C NMR,IR,MS及元素分析进行了表征。     

电有机合成2-取代-5-羟甲基(羧基)呋喃

以5－羟甲基糠醛及其加成产物为原料，用化学或电化学合成法合成了标题化合物，其产物结构经元素分析，IR和^1H NMR确证。     

β-酞酰亚胺基-α-甲基丙酸甲酯的结构分析

为研究取代基对Michael式加成反应的影响，在相转移催化条件下酞酰亚胺与α-甲基丙烯酸甲酯进行加成反应，通过^1H NMR、IR、MS和元素分析对产物结构进行分析，确证其为β-酞酰亚胺基-α一甲基丙酸甲酯；分析了所形成的手性碳结构对邻位亚甲基核磁共振氢谱的影响，并提出了产物分子的碎裂机理。     

环丙烷衍生物的简便合成

报道了4-甲氧基．2-溴代丁烯内酯(4)与几种醇通过串联的双。Michael加成及分子内的亲核取代反应，简便地得到了环丙烷类化合物8。经元素分析、IR、^1HNMR、^13CNMR和MS对目标产物进行了结构表征，其中8a通过单晶培养和x射线晶体测定，确定了它的立体结构。     

24－亚甲基胆甾－4－烯－3β，6α－二醇的结构表征

对采用硼氢化钾－乙醇还原4－烯－3，6－二酮类型的甾酮化合物所获得产物 的结构进行了分析，提出了与文献不同的观点。并通过IR，^1H NMR,^13C NMR等谱 图数据对24－亚甲基胆甾－4－烯－3β，6α－二醇进行了结构表征。     

双香豆素类化合物的合成及表征

香豆素是一类具有重要生理活性的天然产物。本文通过4-羟基香豆素的合成，然后与醛缩合，制备了一类具有双香豆素结构的化合物，对其结构通过^1H NMR、IR及元素分析确证并对其波谱学特征予以了讨论。     

1,5-二氮杂双环[4,3,0]壬碳-5-烯与全氟炔酸酯的反应及其产物的核磁共振研究

1，5—二氮杂双环[4，3，0]壬碳—5—烯(DBN)与全氟炔酸酯反应生成成环化合物。通过对成环产物的^1HNMR、^13C NMR及相关的2D NMR谱的分析，确证了该类化合物的结构，并讨论了其化学位移及J-偶合特征。同时提出了整个反应可能的历程和机理。     

生物降解多功能缓释微球的制备与表征

通过羧甲基壳聚糖接枝二甲基十八烷基环氧丙基氯化铵, 合成水油两溶性的羧甲基壳聚糖十八烷基季铵盐(OQCMC); 并将其作为乳化剂与乳酸-羟基乙酸(PLGA)和羟乙基纤维素(HEC)复合, 利用溶剂挥发法, 构建一种多功能的药物载体缓释系统, 并尝试包裹脂溶性药物盐酸米诺环素. 利用Transmission electron microscopy, Quasielastic laser light scattering, Zeta电位仪, FTIR, 1H NMR等对OQCMC及载药微球进行表征, 并进行药物的体外释放实验. 结果表明: OQCMC可作为一种优良的乳化剂对PLGA微球进行修饰; 并可使复合微球体系带正电, 在提高微球载药率(9.4%)的同时减小微球粒径[(166.4±0.8) nm]; 复合微球体系对盐酸米诺环素具有较好的物理包裹能力, 并有长效缓释作用(PBS, pH＝7.9).     

新型载药壳聚糖季铵盐的合成、结构与性能

通过羧甲基壳聚糖接枝二甲基十八烷基环氧丙基氯化铵, 制备了一系列不同取代度和分子量的羧甲基壳聚糖十八烷基季铵盐(QACMC). 用傅立叶变换红外(FTIR)光谱、核磁共振谱(1H-NMR)、X射线衍射(XRD)谱、差式扫描量热法(DSC)等对其分子结构、结晶和热性能进行研究, 同时研究QACMC的吸湿保湿性能, 并与透明质酸(HA)、壳聚糖(chitosan)和羧甲基壳聚糖(CMC)进行比较. 结果表明, QACMC具有较好的结晶性和热稳定性, 结晶度可达72.3%; 其吸湿保湿性低于透明质酸(HA)和羧甲基壳聚糖, 而受季铵基团取代度和QACMC分子量的影响, 羧酸盐和季铵盐两种亲水基团对QACMC吸湿性的影响不具有协同作用; QACMC对亲脂性药物盐酸米诺环素的载药率可达10.9%(质量分数), 远高于壳聚糖和羧甲基壳聚糖.     

载药磁性阳离子高聚物脂质体的制备及表征

通过羧甲基壳聚糖接枝二甲基十八烷基环氧丙基氯化铵, 合成了水油两溶性的羧甲基壳聚糖十八烷基季铵盐(QACMC), 并用其代替合成磷脂与胆固醇反应, 制备阳离子高聚物脂质体(CPL). 利用阳离子高聚物脂质体包覆水溶性Fe3O4磁流体, 构建磁性阳离子高聚物(MCPL)体系. 用TEM, DLS, VSM, FTIR及Zeta电位仪等对所制样品进行表征. 结果表明, 磁性阳离子高聚物脂质体在水相中可稳定存在, 粒径可达到15.3 nm, 分散性较好, Zeta电位可达到+38.22 mV, 比饱和磁化强度为27.9 A·m2/kg, 具有超顺磁性; MCPL对药物长春新碱的包封率可达到93.1%, 在Tris-HCl(pH=7.4)缓冲溶液中具有良好的缓控释功能.     

Synthesis, Structure and Properties of Novel Quaternized Carboxymethyl Chitosan with Drug Loading Capacity

A modified approach to prepare novel amphipathic octadecyl-quaternized carboxymethyl chitosan (QACMC) was reported, in which carboxymethyl chitosan (CMC), prepared from chitosan, was made to react with glycidyl octadecyl dimethylammonium chloride; thus, the octadecyl quaternary ammonium group was introduced into CMC. The structure and thermal properties of these derivatives were characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy (¹H-NMR), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). The crystalline properties of QACMC were perfect, and it had a high degree of crystallinity. All the chitosan derivatives had good thermal stability when the temperature was lower than 200 °C. The moisture-absorption and retention abilities of QACMC were lower than that of hyaluronic acid (HA) and CMC. The carboxymethyl and quaternary ammonium groups did not show a synergistic effect, and the effects of both the molar mass and the hydrophobic side chains of long alkyl moieties were important. Minocycline hydrochloride was successfully incorporated into QACMC polymeric micelles with a remarkably high efficiency (10.9%, mass fraction). QACMC promises to be a high-potential delivery vector for lipophilic drugs.     

季铵化N,O-(2-羧乙基)壳聚糖的制备及其抑菌性能

以缩水甘油基三甲基氯化铵(GTMA)、缩水甘油基三乙基氯化铵(GTEA)、缩水甘油基三丙基氯化铵(GTPA)、缩水甘油基三丁基氯化铵(GTBA)和缩水甘油基二甲基苄基氯化铵(GDMBA)等活性季铵盐为季铵化试剂,对N,O-2-羧乙基壳聚糖(N,O-2-CEC)进行了化学改性,得到了系列季铵化N,O-2-CEC(QCEC...     

壳聚糖季铵盐-Zn(Ⅱ)催化磷酸双酯与质粒DNA水解动力学

采用壳聚糖与缩水甘油三甲基氯化铵反应制备了壳聚糖季铵盐(HTACC), 研究了其Zn(Ⅱ)配合物HTACC-Zn(Ⅱ)催化DNA的模拟底物对硝基苯酚磷酸双酯(BNPP)水解的动力学过程及其对质粒DNA的催化裂解. 结果表明, HTACC-Zn(Ⅱ)对BNPP的水解反应具有良好的催化活性, 其表观一级速率常数可达到6.7×10-6 s-1, 为BNPP自发水解时的6.0×104倍; 同时, HTACC-Zn(Ⅱ)还能够有效催化质粒DNA(pUC19)的裂解, 使DNA分子由超螺旋结构裂解为开环和线型结构.     

Chitosan-supported Borohydride Reducing Agent

Borohydride exchange resin (BER) a useful reducing reagent has been used in reduction of some carbonyl compounds and acyl halides1. When BER combines with a transition metal catalyst, it can reduce C=C double bonds2, halides2, nitro compounds3, cyano, diazo3 and azide compounds4. The support of BER is the synthetic macromolecule polystyrene. Here, we used chitosan as the support of borohydride. As known, chitosan is a renewable and abundant natural polysaccharide. Scheme 1 Preparat…     

Reaction kinetics of glycidyl trimethyl ammonium chloride and chitosan in 1-allyl-3-methylimidazolium chloride

The modification of chitosan in ionic liquids through homogeneous reactions has advantages including shorter time and simple post-treatment and the generated chitosan derivatives have high degrees of subsititution and good reproducibility. In this paper, we studied the reaction kinetics of glycidyl trimethyl ammonium chloride and chitosan in 1-allyl-3-methylimidazolium chloride. Chitosan concentration, temperature, and reaction time were studied to determine their influence on reaction kinetics. The results indicated that reaction rate increased with increases of both chitosan concentration and temperature. A first-order kinetics equation was generated, where the relationship between reaction rate constant and temperature was determined.     

Studies of the association of chitosan and alkylated chitosan with oppositely charged sodium dodecyl sulfate

Cationic biopolymer chitosan has many applications in food, cosmetic and pharmaceutical industries. Grafting alkylated chains on its backbone can hydrophobically modify this water-soluble polymer.This paper concerns unmodified chitosan, alkylated chitosan and their interactions with a model anionic surfactant, sodium dodecyl sulfate (SDS). The solvent is pH 4 acetic acid solution. The purpose of this study is to highlight the hydrophobicity brought by the alkylated chains by comparing surface tension measurements and rheological properties of hydrophobically modified polymer (HMP) and chitosan solutions at 25 °C.Interactions of chitosan and HMP with surfactant have also been investigated giving information about surface activity and electrical conductivity of such systems. It results that alkylated chitosan/SDS system is more surface active than chitosan/SDS and it offers new potential applications in pharmaceutical and cosmetic fields because of the formation of amphiphilic complexes.     

A new method to prepare macroporous copolymer of glycidyl methacrilate and ethylene dimethacrilate as enzyme carrier

Macroporous copolymer of glycidyl methacrylate and ethylene dimethacrylate containing surface epoxy groups was firstly synthesized with dodecyl alcohol and cyclohexanol as liquid pore-forming agents and nanosize calcium carbonate as solid porogenic agent. The scanning electron microscopy was used to characterize their surface structure. Under the optimum conditions, β-galactosidase from Aspergillus oryzae was immobilized on the support obtained above, and the basic property and the kinetic data of the reaction on immobilized enzyme were determined. These data were compared with those obtained for the enzyme immobilized on the support prepared only with the liquid solution as pore-forming agent. Satisfactory results were obtained in enzyme activity, immobilization yield, pH stability, thermal stability, operational stability, and Michaelis constants K _M. The results indicated that the copolymer of glycidyl methacrilate and ethylene dimethacrylate newly prepared was more suitable to immobilize enzyme than the carrier synthesized with traditional method.