Cyclic di-t-butylsilylenediyl ether group as a convenient protective group for the glycoconjugate synthesis

Treatment of methyl β-d-glucopyranoside, methyl α-d-glucopyranoside, 2-azido-2-deoxy-β-d-galactopyranosyl fluoride, and 1,6-anhydro-β-lactose with di-t-butyldichlorosilane gave the corresponding 4,6-cyclic di-t-butylsilylenediyl ether (4,6-CDBS) derivatives in high yields. It was suggested that the 4,6-CDBS group is quite stable under general conditions for further chemical manipulations such as the acetylation, benzylation and glycosylation reactions employed widely in the carbohydrate chemistry. This protective group was readily removed by treatment with tetrabutylammonium fluoride or triethylamine–3HF complex under mild conditions.