An efficient procedure for the highly selective oxidation of leucomycines to the corresponding 16-membered9- and 13-oxo macrolides using hypervalent iodinates is presented. Both the Dess−Martin periodinane(DMP) and polymer-bound 2-iodoxybenzoic acid (IBX) show clear advantages over the previously employedmanganese dioxide. Key intermediates for a variety of further chemical derivatization methods (2a, 2b)are obtained in very good yields without the requirement of protecting groups.