Molecular Design of New Polymers Having Pendant Acidic Saccharide Moieties and Its Drug Release

天然聚合物及其复合材料再次被认为是有用的生物可降解材料或生物医学材料。以多糖及其重复单元单糖为原料，制备了多种多组分材料。由于D-葡萄糖醛酸类化合物广泛存在于动植物体内，且其内酯可用于商业用途，因此可作为合成新型D-葡萄糖醛酸基两亲性聚合物的原料。本工作首先合成了两种新的单体，分别是作为可聚合官能团的苯乙烯基和甲基丙烯酰基。在60ﾟC下，苯乙烯型和甲基丙烯酰型单体的自由基聚合以及它们与苯乙烯在水或二甲基亚砜中的共聚均相进行，得到了高产率的无色粉状聚合物。通过在三氟乙酸和水(2/1，v/v)的混合物中脱保护，得到的聚合物中的葡萄糖呋喃糖醛酸基部分被转化为具有吡喃糖环的部分。未保护聚合物在不同溶剂中的溶解度与保护聚合物不同。以D-葡萄糖醛酸基-6，3-内酯为原料，合成了另一种以对硝基苯基为药物模型的新型斯特里型单体。它与丙烯酰胺的自由基共聚合得到了一种可用于释放试验的共聚物。

Naturally occurring polymers and their composites have been noted again as useful biodegradable or biomedical materials. Various kinds of multicomponent materials have been prepared from polysaccharides and their repeating units, monosaccharides. Since D-glucuronic acid exists widely as a component of polysaccharides in animals and plants and its lactone was commercially available, it was used as a starting material for synthesis of novel amphiphilic polymers having D-glucuronyl pendants. At first, two kinds of new monomers, styryl and methacryloyl groups as a polymerizable functional group respectively, were prepared in the present work. The radical polymerization of styryl-type and methacryloyl-type monomers and their copolymerization with stirene in water or dimethyl sulfoxide proceeded in a homogeneous phase at 60ﾟC and gave colorless powdery polymer in high yield. Through the deprotection in a mixture of trifluoroacetic acid with water (2/1, v/v), the glucofuranuronyl moiety in the resulting polymers was converted to that having a pyranose ring. Solubility of deprotected polymers was found to be different from that of protected polymers in various solvents. Another new stryl-type monomer having p-nitrophenyl group at the anomeric position as a drug model was also prepared from D-glucurono-6,3-lactone. Its radical copolymerization with acrylamide gave a copolymer, which was useful for the release tests.