Anti-staphylococcal activity and β-lactam resistance attenuating capacity of structural analogues of (-)-epicatechin gallate.

We examined the impact of gradual removal of hydroxyl groups from the A- and B-rings of (-)-epicatechin gallate on antibacterial activity and oxacillin resistance attenuation of an epidemic strain of methicillin resistant Staphylococcus aureus. Removal of both hydroxyls from the B-ring effected a large reduction in oxacillin MIC (from 512 to 0.25 mg/mL at a concentration of 12.5 mg/L); further hydroxyl deletion of the A-ring reduced the oxacillin effect but increased intrinsic anti-staphylococcal activity. Copyright Â