Glucose-based block-co-oligomers with mixed alpha/beta configuration

纤维素和淀粉(直链淀粉)是最重要的多糖，对于利用可再生资源制造生物材料具有至关重要的意义。这两种生物聚合物都是单独由葡萄糖作为单体单元(无水葡萄糖AGU)组成的，它们是线性连接的，没有任何支化。纤维素和淀粉之间的唯一不同之处在于，它们的立体化学构型与当时的非均一碳原子的构型不同。纤维素中的两个AGE通过β-1，4-糖苷键相连，而淀粉中则存在α-1，4-糖苷键。这导致两种多糖的二级结构和性质完全不同。这个简短项目的目的是合成全葡萄糖嵌段共低聚物(作为概念验证)，其中一个嵌段显示α构型，另一个嵌段显示贝塔构型。通过将这些化合物与具有不同结构特征的两个块结合在一起，有望获得新型的生物材料。基于葡萄糖的低聚物α-麦芽三糖和-四糖是淀粉的模型化合物，而β-纤维三糖和四糖是纤维素的模型化合物。化学结构将被确定。此外，还将评估材料特性，如粘弹性特性。

Cellulose and starch (amylose) are the most important polysaccharides and are of paramount significance for manufacturing biogenic materials from renewable resources. Both biopolymers are composed solely of glucose as the monomeric unit (anhydroglucose AGU), which are linearly linked without any branching. The only difference between cellulose and starch is the stereochemical configuration ate the anomeric C1-carbon atom of the AGE. Two AGE in cellulose are linked via a beta-1,4-glycosidic bond, whereas an alpha-1,4-glycosidic bond is found in starch. This results in totally different secondary structures and properties of the two polysaccharides. The aim of the present short project is the synthesis of all-glucose block-co-oligomers (as a proof-of-concept), where on block exhibits an alpha-configuration and the other block the beta-configuration. Form the combination of these compounds with two blocks bearing different structural characteristics, novel biogenic materials are expected. The glucose based oligomers alpha-maltotriose and -tetraose serve as a model compounds for starch, whereas beta-cellotriose und -tetraose are model compounds for cellulose. The chemical structures will be determined. Additionally, material properties such as viscoelastic characteristics will be evaluated.