Synthesis and antibacterial activity of novel 4″-carbamates of 6,11-di-O-methylerythromycin A

A novel series of 4″-carbamates of 6,11-di- O -methylerythromycin A were synthesized and evaluated. These compounds have significant antibacterial activity against Gram-positive pathogens, including erythromycin-resistant but methicillin-susceptible Staphylococcus aureus , erythromycin-resistant and methicillin-resistant Staphylococcus aureus , erythromycin-resistant Streptococcus pneumoniae and Gram-negative pathogens, such as Haemophilus influenzae To our surprise, most of the derivatives tested had potent activity against most resistant bacteria. Among these, compounds 10u , 10v , 10w and 10y were found to have potent activity against most susceptible and resistant bacteria. In particular, compound 10y exhibited excellent antibacterial activity in comparison to others.