Synthesis and enzymatic hydrolysis of lactic acid–depsipeptide copolymers with functionalized pendant groups

✍ Scribed by Tatsuro Ouchi; Tatsuya Nozaki; Akira Ishikawa; Isao Fujimoto; Yuichi Ohya

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 674 KB
• Volume: 35
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19970130)35:2<377::aid-pola21>3.0.co;2-l

✦ Synopsis

Since poly(lactic acid) is the biodegradable polyester having low immunogenicity and good biocompatibility, it is utilized as a medical material. However, poly(lactic acid) is a waterinsoluble crystalline polymer having no reactive side-chain group. Thus, the use of poly(lactic acid) is limited. To modify the properties of poly(lactic acid) and to introduce the functionalized pendant groups to poly(lactic acid), we synthesized two kinds of lactic aciddepsipeptide copolymers with reactive pendant groups, namely poly[LA-(Glc-Lys)] and poly [LA-(Glc-Asp)].

This was done through ring-opening copolymerizations of L-lactide with the corresponding protected cyclodepsipeptides, cyclo [Glc-Lys(Z) ] and cyclo [Glc -Asp(OBzl)], and subsequent deprotection of benzyloxycarbonyl and benzyl groups, respectively. By changing the mole fraction of the corresponding depsipeptide units, the volubility, thermal transition and degradation behavior of the modified poly(lactic acid) could be varied. c 199'7 John Wiley & Sons, Inc.