Disclosed are 1-(arylmethyl)quinazoline-2,4(1H,3H)-diones thereof, represented by the Formula I: wherein Ar, R1-R6 are defined herein. Compounds having Formula I are PARP inhibitors. Therefore, compounds of the invention may be used to treat clinical conditions that are responsive to the inhibition of PARP activity.本發明提供了新穎的1-(芳基甲基)-喹唑啉-2,4(1H,3H)-二酮由式I所示:其中Ar,R1-R6為本文所定義。式I的化合物是PARP抑制劑。因此,本發明的化合物可用於治療由PARP活性異常而導致的疾病。