Boron trifluoride etherate promoted microwave-assisted synthesis of antimalarial acridones

A microwave-assisted, rapid and efficient method using boron trifluoride etherate (BF(3).Et(2)O) for the synthesis of acridones, via an intramolecular acylation of N-phenylanthranilic acid derivatives, has been developed. The reaction proceeds under solvent-free conditions, tolerates a wide range of functional groups, and provides rapid access to a range of acridones in good to excellent yields. Several of the synthesized acridones exhibited potent antimalarial activities against CQ sensitive and multi-drug resistant (MDR) parasites.