Macrolide-type motilin receptor agonists: Acid-stable 12-O-methyl-8,9-anhydroerythromycin A 6,9-hemiacetals

Based on the acid decomposition mechanism of erythromycin A, 12-O-methyl-8,9-anhydroerythromycin A 6,9-hemiacetals were designed and synthesized. These compounds were acid-stable and showed potent in vitro and in vivo motilin agonistic activities, and were thought to be promising orally active prokinetic agents.