报告题目： Synthesis of Degradable Sugar Polymers

报 告 人： Prof. Wenjun Du

                    Department of Chemistry  

                    Central Michigan University ( USA)

主 持 人： 张黎明教授

报告时间： 2014年5月26日 (星期一)上午10:30-11:40

报告地点： 丰盛堂A106

附注：Prof. Wenjun Du 在美国University of North Carolina、University of California Davis、Washington University及Central Michigan University学习和工作10多年，在有机化学、高分子化学和生物材料等方面开展了不少有特色的研究工作；另外，他目前在Central Michigan University还负责所在学院和系的招生工作，也有意招收中山大学化学学院学生或毕业生到他领导的课题组攻读学位或进行博士后研究。欢迎对上述研究领域感兴趣的师生及有意出国深造的本科生、研究生与会同Prof. Du进行交流和探讨！

报告论文摘要：

Synthesis of Degradable Sugar Polymers

     Sugar polymers, with excellent biocompatibility and degradability, are ideal polymers for biomedical applications. Historically, access to these polymers has been limited due to challenges in the synthesis. In this presentation, two synthetic methods will be reported to address this long-standing challenge. The first method employed 2,3,4-tri-O-acetyl-?-D-glycopyranosyl bromides as the di-functional AB-monomers. When appropriate promoters, such as silver carbonate was used, the reaction may occur in a polycondensation manner. Under regular heating, the reactions were ineffective, giving oligomers with molecular weights of only 1-2 kDa. However, when microwave energy was employed, oligomers with molecular weights of 4.76 kDa were obtained.

     The second approach employed the same monomers however used different promoters to achieve the formation of orthoester linkages between each sugar unit. In this case, when tetrabutylammonium iodide (TBAI) was used as a promoter, polymers with molecular weights of 6.9 kDa was obtained. Because of the highly acid-labile orthoester linkages, the synthesized polymers were highly pH-responsive.