An improved and general synthesis of N-glycosylated oxindoles by SET-reduction of isatin-N-glycosides

Oxindole- N -glycosides were efficiently prepared by reduction of acetyl- and formyl protected isatin- N -glycosides with low-valent titanium and following cleavage of the protecting groups under basic conditions. The products could be isolated as pure anomers – no noticeable anomerization took place. • A variety of oxindole- N -glycosides were efficiently prepared from readily available starting materials. • The products were isolated as pure anomers. • Products could be deprotected and are not readily available by other methods.