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维生素B12环B酰亚胺前体及琥珀胺类药物不对称合成的研究 总被引:1,自引:1,他引:0
从γ-丁内酯合成了维生素B12环B酰亚胺前体及琥珀酰胺类药物的3个衍生物,进行了其中不对称季碳的构筑,改进了TiCl3还原硝基乙烯类化合物的反应,同时发现了一个简便合成乙琥酰胺环的新方法。 相似文献
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液晶性芳香酰胺化合物的合成 总被引:7,自引:0,他引:7
合成了一系列炖粹以酰胺基为中心桥键的刚性芳香酰胺小分子化合物,并对其作了表征,发现其中有些化合物具有液晶性。酰胺键之间能形成很强的分子间氢键,使芳香酰胺小分子化合物的熔点很高,难于形成液成液晶态。研究发现,如果在这类化合物的中心苯环上引入合适的取代基以减弱分子间氢键,同时引入合适的末端基时,则可使芳香酰胺化合物生成液晶相的能力增强。 相似文献
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在甾体的甾核或支链上引入不同的官能团后可得到不同生理活性的化合物,它们有可能会成为人类治疗不同疾病的药物,因此甾体药物除了作为传统激素类药物使用外,在抗肿瘤药物、抗炎药物中的应用也成为甾体的重要研究内容之一。含有酰胺官能团的甾体化合物具有很好的生物活性。本文按照酰胺基团在甾体酰胺化合物中的位置进行分类,同时结合本课题组在甾体酰胺化合物的合成和生理活性研究方面所取得的一些成果,概述了近几年来新合成及发现的甾体酰胺类化合物及其衍生物的生理活性及研究进展,包括作为抗肿瘤药物的甾体酰胺化合物的设计、筛选、对5α-还原酶的抑制作用、抑制肿瘤细胞生长增殖活性及抗菌作用,并对此方面的发展趋势、应用前景作了展望。 相似文献
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脂肪族酰胺二元醇的合成与表征 总被引:3,自引:1,他引:3
以DL-乳酸、ε己内酯及乙二胺和己二胺为原料合成了四种结构的脂肪族酰胺二元醇,并用IR,^1HNMR,DSC对酰胺二元醇的结构进行了表征。 相似文献
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In this work, a new kind of aliphatic polyesteramide (PEA) copolymer based on -caprolactone and 6-aminocaproic acid was synthesized by the melt polycondensation method. Biodegradable PEA fibers were processed by the melt-spinning method. 1H-NMR, FTIR, SEM, and tensile testing were used to characterize the degradation of PEA fibers in concentrated alkaline solution. The PEA fiber undergoes surface erosion in such concentrated alkaline solutions. 相似文献
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Zhiyong Qian Sai Li Yi He Hailian Zhang Xiaobo Liu 《Colloid and polymer science》2004,282(10):1083-1088
Biodegradable polyesteramide copolymer P(CL/AU) based on -caprolactone and 11-aminoundecanoic acid was synthesized by the melt polycondensation method. Polyesteramide (PEA) microspheres were prepared by a simple O/W emulsion solvent evaporation method. The effects of variations in preparation parameters (such as emulsifier concentration, polymer concentration, polymer solution adding rate, stirring rate, and whether vacuum was applied) were studied in detail. The obtained microsphere morphologies were observed using an optical microscope and via scanning electron microscopy (SEM). The particle size distribution was determined using a Malvern laser particle sizer. When the PEA microspheres were incubated in PBS saline, the particle size increased at first, and then decreased after a longer time period; the theory that this behavior was due to degradation of the microspheres was confirmed by SEM. 相似文献
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聚酯酰胺的合成及表征 总被引:1,自引:0,他引:1
用两种方法合成了聚酯酰胺(PEA)共聚物.一种是两步法,即先合成对苯二甲酸乙醇酰胺(BAET)单体,然后与对苯二甲酸乙二酯(BHET)共缩聚;另一种是一步法.即在酯交换反应中直接添加乙醇胺(EA).两种方法制得的聚酯酰胺(PEA)共聚物测试证明了为产物,并分析了合成中的化学反应. 相似文献
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聚酯酰胺的合成及表征 总被引:2,自引:0,他引:2
用两种方法合成了聚酯酰胺(PEA)共聚物.一种是两步法,即先合成对苯二甲酸乙醇酰胺(BAET)单体,然后与对苯二甲酸乙二酯(BHET)共缩聚;另一种是一步法.即在酯交换反应中直接添加乙醇胺(EA).两种方法制得的聚酯酰胺(PEA)共聚物测试证明了为产物,并分析了合成中的化学反应. 相似文献
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《高分子科学杂志,C辑:聚合物评论》2013,53(3):231-274
Abstract The aim of this review is to show the relationships between the structure, the process, and the properties of biodegradable multiphase systems based on plasticized starch (PLS), the so‐called “thermoplastic starch.” These mutiphase materials are obtained when associating association between plasticized starches and other biodegradable materials, such as biodegradable polyesters [polycaprolactone (PCL), polyhydroxyalkanoates (PHAs), polylactic acid (PLA), polyesteramide (PEA), aliphatic, and aromatic copolyesters], or agro‐materials (ligno‐cellulosic fiber, lignin etc.). Depending on materials (soft, rigid) and the plastic processing system used, various structures (blends, composites, multilayers) can be obtained. The compatibility problematic between these hetero‐materials is analyzed. These starchy products show some interesting properties and have some applications in different fields: packaging, sports, catering, agriculture and gardening, or hygiene. 相似文献
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Pilar Izu María Eugenia Muoz Juan J. Pea Anton Santamaría 《Journal of Polymer Science.Polymer Physics》1993,31(3):347-356
Viscosity measurements on two commercial thermotropic liquid crystalline polymers (LCPs) (a copolyester and a polyesteramide) were performed using both capillary and slit die methods. The results are in agreement with those presented in the literature for the same LCPs, when the measurements are carried out with a L/D = 30 die; these results are affected more by Bagley corrections for the polyesteramide than for the copolyester. For both LCPs, viscosities measured in the slit die are lower than those obtained by capillary rheometry. Nevertheless, the difference is much bigger in the case of the polyesteramide, for which a reduction by a factor of 3 is observed. This is not due to the preshear or thermal history, since the same piston-barrel system and thermal treatment were applied in both types of measurements. Depending on the polymer sample and temperature, concave and convex curvatures were observed in the pressure profiles during the slit flow. From these curvatures, the pressure coefficient α of viscosity was evaluated. However, in the case of the polyesteramide the convex curvature leads to a negative coefficient (the viscosity decreases with pressure, instead of increasing). This result may be explained by envisaging a change in the structure of the melt along the slit length. © 1993 John Wiley & Sons, Inc. 相似文献
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Pan He Zhaohui Tang Lin Lin Mingxiao Deng Xuan Pang Xiuli Zhuang Xuesi Chen 《Macromolecular bioscience》2012,12(4):547-556
Biodegradable and pH‐sensitive PEAs based on dual amino acids are designed, synthesized, and characterized. Insulin can be loaded into the PEA microspheres by a solid‐in‐oil‐in‐oil technique with high encapsulation efficiency. The feasibility of PEA microspheres as oral insulin delivery carriers is evaluated in vitro and in vivo. The hydrophobic leucine groups on PEA seem to play an important role in the pH‐dependent release mechanism and cytotoxicity of PEA microspheres. Oral administration of insulin‐loaded PEA microspheres to streptozotocin‐induced diabetic rats at 60 IU kg?1 is able to reduce fasting plasma glucose levels to 49.4%. These results indicate that PEA microspheres are potential new vehicles for insulin oral delivery.
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Yanrong Ren Xuesong Jiang Jie Yin 《Journal of polymer science. Part A, Polymer chemistry》2009,47(5):1292-1297
A novel multiresponsive poly(ether tert‐amine) (PEA) was synthesized by nucleophilic addition/ring‐opening reaction of commercial poly(ethylene oxide) (PEO), poly(propylene oxide) (PPO), and di‐epoxy and di‐amine monomer. The process of synthesis was very simple and green in ethanol as reactive media. These PEAs exhibit sharp response to temperature, pH, and ionic strength, with adjustable and sharp phase transitions in the range of 27–100 °C. The lower critical solution temperature (LCST) of PEA's aqueous solution presents a linear relationship to the PEO content (y = 35.7 + x), indicating well‐tunable LCST. The concentration of PEA has no obvious effect on LCST. Therefore, PEA will be potential in applications of drug delivery, separation, and biotechnology. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1292–1297, 2009 相似文献
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D. Raghavan X. Gu T. Nguyen M. Vanlandingham 《Journal of Polymer Science.Polymer Physics》2001,39(13):1460-1470
Characterization of polymer coatings microstructure is critical to the fundamental understanding of the corrosion of coated metals. An approach for mapping the chemical heterogeneity of a polymer system using chemical modification and tapping‐mode atomic force microscopy (TMAFM) is demonstrated. This approach is based on the selective degradation of one of the phases in a multiphase polymer blend system and the ability of TMAFM to provide nanoscale lateral information about the different phases in the polymer system. Films made of a 70:30 polyethyl acrylate/polystyrene (PEA/PS) blend were exposed to a hydrolytic acidic environment and analyzed using TMAFM. Pits were observed to form in the PEA/PS blend films, and this degradation behavior was similar to that of the PEA material. Using these results, the domains in the 70:30 blend were identified as the PS‐rich regions and the matrix as the PEA‐rich region. This conclusion was confirmed by Fourier transform infrared‐attenuated total reflection analyses that revealed the hydrolysis of the PEA material. TMAFM phase imaging was also used to follow pit growth of the blend as a function of exposure time. The usefulness of the chemical modification/AFM imaging approach in understanding the degradation process of a coating film is discussed. © 2001 John Wiley & Sons, Inc. J Polym Sci B Part B: Polym Phys 39: 1460–1470, 2001 相似文献