FACILE PREPARATION OF PROTECTED FURANOID GLYCALS FROM THYMIDINE

The synthesis of O-silyl- and O-acyl-protected furanose glycals from f ree thymidine was investigated. The method of glycal formation reporte d by Pedersen et al. was successfully expanded to include 5-ester (tol uoyl) protected glycals as well as various combinations of 5'-ester an d 3- and 5-tert-butyldimethylsilyl and tert-butyldiphenylsilyl protect ion. 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%.