Waddell S T, Santorelli G M, Blizzard T A, Graham A, Occi J
Merck Research Laboratories, Rahway, NJ 07065, USA.
Bioorg Med Chem Lett. 1998 Jun 2;8(11):1321-6. doi: 10.1016/s0960-894x(98)00227-3.
Direct O-methylation of various derivatives of 9-deoxo-8a- and 9a-aza-8a-homo-erythromycin (2',3'-bis-Cbz protected) gives 6-OMe derivatives only in a small number of special cases. The 6-OMe-azalides can, however, be synthesized beginning from clarithromycin.