Facile Preparation of Protected Furanoid Glycals from Thymidine

Abstract

The synthesis of O -silyl- and O -acyl-protected furanose glycals from free thymidine was investigated. The method of glycal formation reported by Pedersen et al. was successfully expanded to include 5-ester (toluoyl) protected glycals as well as various combinations of 5‘-ester and 3- and 5- tert -butyldimethylsilyl and tert -butyldiphenylsilyl protection. Gram quantities of furanoid glycals can be prepared in a few days in two−four synthetic steps in overall yields ranging from 17 to 80%.