Ⅰ. Synthesis Of Glycosides Of Arabinose Ⅱ. Tudy On The Synthesis Of Oligosaccharides And Synthesis Of Oligosaccharide In Muscaroside

Glycosides of arabinose distribute widely in nature and most of them is biologically active. For example, β-peltatin A, α — L-arabinofuranoside has strong antitumor activity. O-Glycosidesfuranoside and C-glycosides of arabinose arethe important components of some biologically active natural products. Although some progresses have been made in the synthesis of arabinosides, their synthetic methods are very tedious and complex: and the yield of them is very low. Therefore it is necessary to modify and improve the methods for the synthesis of arabinosides.The selective synthesis of α —anomers of O-, C-glycosides and 1-0-acyl-arabinofuranosides via arabinofuranosyl trifluoro-acatate was studied.Trifluoroacetoxy group is one of the best leaving group for the preparation of C, N, S-glycosides of glucose, mannose and nucleosides etc. Now the application of trifluoroacetoxy as leaving group for the synthesis of arabinosides and the relationship of various reaction...