Novel azalides derived from 16-membered macrolides. III. Azalides modified at the C-15 and 4″ positions: Improved antibacterial activities

The design and synthesis of 16-membered azalides modified at the C-15 and 4″ positions are described. 3-Hydroxyl azalides having an arylpropenyl and an ethylcarbamoyl group at the C-15 and C-4″ position, respectively, exhibited significant improvement in antibacterial activities against erm-resistant Streptococcus pneumoniae.