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多肽/聚氨基酸分子由于优异的生物相容性、序列可控性和高生物活性等特点,已经被广泛应用于肿瘤诊疗等生物医学领域.然而,这些分子仍然存在一定的缺陷,如光学性质不佳、半衰期短与清除速率快等.本文简述了通过对多肽/聚氨基酸分子的序列设计、侧链修饰和自组装条件进行调控,赋予其可控的光学性质以用于生物成像,更优异的药代动力学和药效学以获得更好的治疗效果.重点介绍了该领域以及本课题组近期关于多肽/聚氨基酸自组装纳米材料的构筑理念及其在肿瘤诊疗领域的应用研究,并对该领域的挑战和未来发展前景进行了展望. 相似文献
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二联苯和氨基酸构建的大环化合物自组装研究 总被引:3,自引:0,他引:3
以二联苯作为模板,设计并合成了3个二联苯和氨基酸构建的大环化合物.晶体结构结果研究发现,在固态,这些大环化合物分别组装成了管状、三维网状和链状的超分子结构,其中,C-H…O氢键在维持这些大环的组装方面发挥了重要作用.这将有助于进一步增加对分子自组装、分子识别以及生物大分子的稳定性方面的理解. 相似文献
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该文以三氯化磷(PCl3)、三氯氧磷(POCl3)和环三聚磷酸(P3M)为辅助试剂,进行了苯丙氨酸(Phe)自组装成肽反应的研究,利用液相色谱-质谱联用以及电喷雾多级质谱技术对反应体系组分进行了分析和结构鉴定。考察了不同缩合试剂和反应时间对苯丙氨酸成肽反应的影响,并初步探讨了无机磷试剂辅助下芳香侧链氨基酸的成肽机理。反应中有Phe系列寡肽生成,同时也有少量环肽存在。该研究可为寡肽的合成工艺开发提供参考,同时对于研究生命起源中的前生命化学物质有着重要的理论意义和学术价值。 相似文献
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本文报道了O-烷基-O-(2'-甲酰缩氨基硫脲苯基)-N-烷基硫代磷酰胺类化合物的合成方法, 化合物3c和3e具有良好的除草活性。 相似文献
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2-Phenoxy- and 2-dialkylamino-2-oxa-1,3,2-oxathiaphospholanes react with PCl5 with ring opening and formation of the corresponding acid chlorides of thiophosphoric acid. Under analogous conditions, 2-phenoxy-2-oxo-1,3,2-oxathiaphosphorinanes do not react with PCl5, while acid chlorides of thiophosphoric acid are formed in low yield along with other products in the reaction of 2-dialkylamino-2-oxo-1,3,2-oxthiaphosphorinanes with PCl5.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Science Center, Russian Academy of Sciences, 420083 Kazan. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2676–2678, November, 1992. 相似文献
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Solid microspheres that were phase-separated in aqueous suspensions of thermal heterocomplex molecules made by heating a mixture of proline and aspartic acid transformed into husk-like microcapsules as pH increased. The transformation from solid microspheres into microcapsules proceeded at two different time scales. Rapid dissolution of thermal heterocomplex molecules from the outer surfaces only during a short period was followed by slow dissolution of those molecules from their inside. The difference of the rates of dissolution led to the formation of microcapsules carrying smaller inner kernels as remnants. 相似文献
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Vommina V. Sureshbabu Rao Venkataramanarao Shankar A. Naik G. Chennakrishnareddy 《Tetrahedron letters》2007,48(39):7038-7041
An efficient synthesis of tetrazole analogues of amino acids starting from Nα-Fmoc amino acid in a three-step protocol is reported. The free amino tetrazoles were obtained in good yields and with excellent purity after removal of the Fmoc group. The synthesis of analogues of aspartic and glutamic acids in which the 5-tetrazolyl moiety is inserted at the β/γ carboxyl group starting from Fmoc-Asn and Fmoc-Gln and the incorporation of these tetrazoles into peptides are also described. 相似文献
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A novel, rugged sheathless capillary electrochromatography-electrospray ionization (CEC-ESI) device, in which an open-tubular separation capillary and an electrospray tip are integrated with a Nafion tubing junction, is coupled to mass spectrometry (MS) for the analysis of amino acids and peptides. A stable electrospray was generated at nanoflow rates by applying a positive electrical potential at the Nafion membrane junction. To sustain the stable spray, an electroosmotic flow (EOF) to the spray was supported by coating the fused silica capillary with Lupamin, a high-molecular-weight linear positively charged polyvinylamine (PVAm) polymer, which also minimizes analyte adsorption. Electrochromatographic separation of amino acids and peptides was further enhanced by the chromatographic selectivity of Lupamin stationary phase for these molecules. The device was very reliable and reproducible for CEC-ESI-MS analyses of amino acids and peptides for over a hundred injections. The separation and detection behaviors of amino acids and peptides under different conditions including pH, concentration, and composition of mobile phases on Lupamin-coated and uncoated capillaries have been investigated. The relationship between nano electrospray stability and EOF is discussed. 相似文献
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Angel H. Romero 《合成通讯》2016,46(3):287-291
An alternative, convenient, and efficient procedure for the synthesis of 2-chloroquinoline-3-carbaldehyde was carried out by the action of Vilsmeier’s reagent on acetanilides using phosphorus pentachloride as chlorinating agent in place of phosphoryl chloride, obtaining good yields for activated acetanilides. The optimal conditions for this reaction requires only 4.5 equivalents of phosphorus pentachloride, 3 equivalents of N,N-dimethylformamide, and 1 equivalent of the corresponding acetanilide at 100 °C for approximately 4 h. 相似文献
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建立了氨基酸同位素稀释液相色谱-串联质谱法准确测定合成肽段绝对含量的方法。实验中对合成肽段的纯度进行了表征,色谱纯度表征结果为99%以上,质谱纯度为90%以上。在肽段溶液中加入13C标记的氨基酸后进行酸溶液水解时间的优化,水解后的氨基酸直接经液相色谱分离和质谱检测,结果表明肽段中的被测氨基酸在150 ℃、6 mol/L HCl溶液水解4~6 h就可以达到水解平衡。每个肽段选择两个或两个以上的被测氨基酸,测得随机选择的5种合成肽段的绝对含量为62.07%~88.18%,测定结果的相对标准偏差小于8%,相对误差小于5%,均满足定量要求。除常用的被测氨基酸苯丙氨酸、缬氨酸、异亮氨酸外,还考察了选择赖氨酸和精氨酸作为被测氨基酸的可行性,实验结果表明增加精氨酸为被测氨基酸是可行的,从而进一步增加了方法的普适性。该方法的建立避免了色谱法定量时氨基酸衍生化处理带来的副反应影响及操作繁琐等问题,提高了肽段含量测定的准确度和精密度,为肽段含量的准确测定提供了一种新的方法。 相似文献
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The analytical performances of two triple-quadrupole instruments, which differ in their atmospheric-pressure sources, were evaluated for native amino acid analysis. The Applied Biosystems/Sciex API 300 instrument was equipped with a turboIon Spray source and a curtain gas interface while the Waters/Micromass Quattro Ultima instrument was characterized by its Z-spray source. Liquid chromatography/mass spectrometry analysis of native amino acids requires volatile ion-pairing mobile phase additives (mainly perfluorinated carboxylic acids). The effects of the structure and concentration of the ion-pairing reagents as well as the organic modifier percentage on the electrospray response of amino acids were studied in detail. The most favourable chromatographic conditions depend strongly on the mass spectrometer used. Several instrumental parameters were also studied, including spray voltage, transmission lens voltages, temperature of desolvation and auxiliary gas flow rates. The results show substantial qualitative differences depending on the instrument geometry. The quantitative performances of the two triple-quadrupole mass spectrometers were evaluated in terms of limits of detection and quantification. The effects of the matrix on the analyte ionization were also examined, and the long-term stability of the electrospray performance was studied over 12 h using a mobile phase containing the perfluorinated ion-pairing reagents. The study provides information on the robustness of the MS instrument and its detection sensitivity towards native amino acid analysis. It appears that each instrument has its good and bad points since one provides higher sensitivity while another is more robust. 相似文献
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Cserháti T 《Biomedical chromatography : BMC》2007,21(8):780-796
The newest results in the application of various chromatographic methods (gas-liquid chromatography, liquid chromatographic techniques, electrically driven systems) for the separation and quantitative determination of amino acids and short peptides in pure state and in complicated matrices are compiled. The results are concisely described and critically evaluated. The future trends of the chromatographic analysis of amino acids and short peptides are briefly discussed. 相似文献
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《Journal of separation science》2017,40(7):1482-1492
We developed a straightforward, robust, and relatively fast method for the analysis of amino acids by mixed‐mode high‐performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry. The method does not involve derivatization and allows the detection of 21 amino acids, representing a wide range of isoelectric points, in less than 40 min. Chromatographic separation was governed by a silica‐based mixed‐mode column providing simultaneous hydrophobic and ion exchange separation mechanisms. The use of tandem mass spectrometry increased selectivity, reducing potential problems associated with poor selectivity in the chromatographic system. For an injection volume of 1 μL, we obtained detection limits <3 μM for the majority of analytes. For all analytes, a linearity of r > 0.99 was obtained, recovery in matrix was >86%, and the retention times were highly reproducible. The method was successfully applied to soil solution and fungal culture samples, demonstrating the advantages in successfully avoiding issues associated with high amounts of substances that may interfere with derivatization‐based methods. This method represents an alternative to derivatization‐based methods and can be applied in areas where sample matrices are highly complex. 相似文献
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[60]-Fullerene functionalized amino acids with 4-6 methylene spacers from α-carbon to the nitrogen atom of fulleropyrolidine and corresponding multifullerene peptides have been synthesized. 相似文献