Chemical modification of erythromycins. IV. Synthesis and biological properties of 6-O-methylerythromycin B.

6-O-Methylerythromycin B has been synthesized from erythromycin B via regioselective methylation of the 6-hydroxyl group in 71% overall yield. This compound shows in vitro antibacterial activity comparable to erythromycins A and B and exhibits superior in vivo activity with improved pharmacokinetic properties.