Synthesis of some 2-alkoxy glyco-[2,1-d]-2-oxazolines and evaluation of their glycosylation reactivity

The synthesis of the title compounds using intramolecular nucleophilic substitution reactions in the molecules of the corresponding 2-alkoxycarbonylamino-2-deoxy glucosyl halides was studied. It was found that in contrast to the 2-alkyl (aryl) glyco-[2,1-d]-2-oxazolines, the synthesis of the target 2-alkoxy glyco-[2,1-d]-2-oxazolines was possible only in highly basic media. The synthesized 2-alkoxy oxazoline derivatives turned out to be active glycosyl donors and were used for stereoselective 1,2-trans glycosylation reactions catalyzed by weak protic acid under very mild conditions, thus preventing anomerization and other side reactions. As a result of this glycosylation, the glycoside and oligosaccharide derivatives containing urethane N-protecting groups were formed.