Regioselective Control in the Oxidative Cleavage of 4,6-O-Benzylidene Acetals of Glycopyranosides by Dimethyldioxirane
摘要:
The oxidative cleavage of 4,6-O-benzylidene acetals of glycopyranosides using dimethyldioxirane (DMDO) leads to the corresponding hydroxy-benzoates lent yields. With a Proper choice of the neighboring protecting groups, this oxidative fragmentation provides the 6- or 4-hydroxyl derivatives in a highly regioselective manner.
Efficient and highly selective glycosylation reactions of peracetylated β-D-N-acetylglucosamine are described using catalytic iron(III) triflate and 2,4,6-tri-tert-butylpyrimidine (TTBP) under microwave conditions. We have demonstrated that the formation of β-(16) and β-(13) linked disaccharides are obtained in high yields in the presence ofvarious protecting groups.
The oxidative cleavage of 4,6-O-benzylidene acetals of glycopyranosides using dimethyldioxirane (DMDO) leads to the corresponding hydroxy-benzoates lent yields. With a Proper choice of the neighboring protecting groups, this oxidative fragmentation provides the 6- or 4-hydroxyl derivatives in a highly regioselective manner.