Synthesis and antibacterial activity of racemic paecilocin A and its derivatives against methicillin-sensitive and -resistant Staphylococcus aureus

Abstract A total synthesis in four steps of racemic paecilocin A, a natural marine phthalide is reported. The synthetic pathway includes an iodine-magnesium exchange followed by a condensation on an aldehyde and represents a sufficiently flexible approach to allow the synthesis of twelve analogs. The synthesized compounds were investigated for their antibacterial activity against methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant strain (MRSA). Three analogs were found to have similar or better antibacterial activity than the natural compound on MRSA.