N-糖链介导了糖蛋白的多种作用，对蛋白质功能发挥及结构稳定起着关键作用。糖链的结晶困难使其及缀合物三维构象研究成为制约糖生物学发展的瓶颈。近来随着蛋白质化学全合成技术的成熟，基于蛋白质对映异构体合成的（准）消旋体结晶策略成为蛋白质等生物大分子结晶学研究的新手段，其在结晶成功率、解析难度简化及解析分辨率等方面远优于单一异构体结晶技术，但糖链结晶及构象研究未见报道。基于结晶学理论分析及消旋体结晶策略实践的优势，推测利用该策略将有可能实现糖链结晶及空间构象解析上的突破。课题拟在前期L-糖合成方法学研究基础上，以N-连接寡糖(肽)的对映异构体合成为基础，探索消寡糖旋体结晶的可行性。L-单糖的合成方法及规模化制备、寡糖(肽)对映体的合成、结晶学条件摸索及解析等研究将丰富L-寡糖合成化学、糖结晶学内容，为糖链三维结构信息获取、空间构象研究开辟新思路，为深入理解、阐明相关糖链作用分子机制奠定基础。

N-glycan play a crucial role in the functioning of proteins and structural stability. The difficulty of crystallization of sugar chains makes its three-dimensional conformational research a bottleneck restricting in the development of sugar biology. Recently, with the maturation of protein synthesis technology, the racemic crystallization strategy based on protein enantiomer synthesis has become a new method for the crystallization of biological macromolecules such as protein. The rate of crystallization is improved and analytical difficulty is simplified And the analytic resolution is far superior to the single isomer crystallization technology. However, the sugar chain crystallization and conformation research has not been reported. Based on the crystallographic theory and the advantages of racemic crystallization strategy, it is speculated that it is possible to realize the breakthrough of sugar chain crystallization and spatial conformation analysis. Based on the previous studies on the synthesis of L-sugar, the feasibility of the racemic oligosaccharide crystals would be explored on the basis of the enantiomer synthesis of N-linked oligosaccharides. L-monosaccharide synthesis method and large-scale preparation, oligosaccharide (peptide) enantiomer synthesis, the exploration of the crystallization conditions and analysis of the structure will enrich the knowledge of L-oligosaccharide synthetic chemistry, sugar crystallographic content and sugar chain three-dimensional structure information acquisition.