Abstract: In order to improve tacrine's pharmacological activity and reduce its adverse effects, three of tacrine derivatives have been synthesized through acetylation, chloroacetylation and butylation of the amino group of tacrine. In view of the excellent hydrophilicity of piperazinyl group, it was incorporated into the acridine molecule and 9-（2-piperazinyl）acetylamino-1,2,3,4-tetrahydroacridine was synthesized. The structures of these compounds were characterized by elemental analysis, IR, （）¹H NMR and MS.