Reaction of O-benzyl- and 4,6-O-benzylidene-D-gluco- and D-galactopyranose derivatives with amido-stabilized sulfur ylides: stereoselectivity and reactivity

The reaction of N,N-diethyl-2-(dimethylsulfuranylidene)acetamide (1) with protected monosaccharides was extended to a number of O-benzyl- and 4,6-O-benzylidene-d-gluco- and -D-galactopyranose derivatives. Results verified the importance of the protecting group at the hydroxyl on C-2 of the starting 4,6-O-benzylidene-d-glucopyranose. Also, the size of the substituent at C-2 and the presence of a 4,6-O-benzylidene group were found to be essential factors in determining the yield and stereoselectivity of these reactions.