報告題目: Synthesis of Degradable Sugar Polymers
報 告 人: Prof. Wenjun Du
Department of Chemistry
Central Michigan University ( USA)
主 持 人: 張黎明教授
報告時間: 2014年5月26日 (星期一)上午10:30-11:40
報告地點: 豐盛堂A106
附注:Prof. Wenjun Du 在美國University of North Carolina、University of California Davis、Washington University及Central Michigan University學習和工作10多年,在有機化學、高分子化學和生物材料等方面開展了不少有特色的研究工作;另外,他目前在Central Michigan University還負責所在學院和系的招生工作,也有意招收中山大學化學學院學生或畢業生到他領導的課題組攻讀學位或進行博士后研究。歡迎對上述研究領域感興趣的師生及有意出國深造的本科生、研究生與會同Prof. Du進行交流和探討!
報告論文摘要:
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.