The present invention provides aryl ketone compounds and compositions containing them which facilitate the delivery of active agents. The aryl ketone compounds have the formula or a salt thereof, where n=1 to 9, and R1 to R5 are independently hydrogen, C1 to C4 alkyl, C1 to C4 alkoxy, C2 to C4 alkenyl, halogen, hydroxyl, —NH—C(O)—CH3, or —O—C6H5.