Synthesis of rapamycin glycoconjugates via a CuAAC-based approach

The conversion of the C40 secondary hydroxyl group of rapamycin into the azido group was followed by copper catalyzed cycloaddition of the resulting azido-rapamcin with various unprotected propargyl O- and S-glycosides and a C-ethynyl derivative. This approach furnished a collection of triazole-bridged rapamycin glycoconjugates (14 examples) in 44–83% isolated yield.