Aqueous Glycosylation of Unprotected Sucrose Employing Glycosyl Fluorides in the Presence of Calcium Ion and Trimethylamine

摘要: We report a synthetic glycosylation reaction between sucrosyl acceptors and glycosyl fluoride donors to yield the derived trisaccharides. This proceeds at room temperature in an aqueous solvent mixture. Calcium salts tertiary amine base promote with high site-selectivity for either 3′-position or 1′-position of fructofuranoside unit. Because nonenzymatic oligosaccharide syntheses are underdeveloped, mechanistic studies were carried out order identify origin selectivity, which we hypothesized was related structure hydroxyl group array sucrose. The solution conformation various monodeoxysucrose analogs revealed co-operative nature groups mediating both this bond-forming same time.