Research On The Synthesis Of The Core Trisaccharide Of The N-glycans

Cancer is one of the major diseases that seriously threat human life. N-glycans in some tumor cells can reduce cell migration rates. However, only a few of these oligosaccharides can be isolated from natural sources due to their microheterogeneity. This situation limits the study of the mechanism of the function of N-glycans in cancer cells. While chemical synthesis of these oligosaccharides is an effective way to solve this problem. All types of N-glycans comprise a common core structure, theβ-1,4-linked D-mannosyl chitobiose unit, suggesting that Efficient assembly of this core structure will no doubt facilitate the development of practical synthesis of N-glycans. While this paper provides a route that constructs the core trisaccharide highly efficient.1. Using the method Established by our laboratory, the donor with 2,3-OH protected by different group was synthesized. These donors participate the glycosylation with two other building blocks respectively .2. One of those donors is found to match with the two other building blocks in one-pot glycosylation. Selective removal of the protecting group in C-2 position of the resulting trisaccharide was conducted successfully. The core trisaccharide was abtained by the subsequent intramolecular SN2 nucleophilic substitution of 2-OH.3. A convenient synthesis of the core trisaccharidic scaffold for the assembly of N-glycans, which greatly simplified the procedure for construction of theβ-mannoside, was constructed. Owing to its facility and mild reaction conditions, the procedure can be applied to access a series of N-glycans rapidly.