(1)Regioselective C6 Phosphorylation of Carbohydrates(2)Chloride–mediated Stereoselective Glycosylation Reaction of Glucosamine Building Blocks

• Main Authors: Chun-Wei Chang, 張峻瑋
• Other Authors: Ping-Shan Lai
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/3s8598

碩士 === 國立中興大學 === 化學系所 === 101 === In living organisms, the conversion of sugars to sugar 6-phosphates plays an important role in the initial stage of carbohydrate metabolisms, which result in the form of glycogen for the storage of energy. Therefore, in the first part of this thesis, a regioselective one-pot C6 phosphorylation of a series of sugar molecules has been developed and the roles of these sugar 6-phosphates in carbohydrate metabolisms are preliminarily investigated. Controlling the stereoselectivity in glycosylation reactions is one of the most challenging issues in carbohydrate chemistry. Different from commonly believed in the literature, we have found that the chloride from the promoters actually participates into the glycosylation reactions and affects the stereoselectivity. In the second part of this thesis, we focus on identifying the glycosyl chloride intermediates of glucosamine derivatives in the glycosylation reactions and how they influence the stereoselectivities.