Synthesis of several novel 14-membered ketolides bearing modified 5-O-4′-[1,2,3] triazol desosamine side chain

4-Azido modified desosamine 4a was synthesized and coupled to erythronolide 9. Using trichloroacetimidate donor in the presence of TMSOTf was considered as the most efficient condition for the glycosylation reaction. Five novel 14-membered ketolides 12a–e bearing modified 5-O-4′-[1,2,3] triazol desosamine side chain were synthesized by the azide/alkyne click chemistry method.