The present invention discloses a series of pyrimidone derivatives represented by formula (I) or a salt thereof, or a solvate thereof or a hydrate thereof: ##STR00001## Wherein X, Z, R1, R2, R3, R4, R5, R6, R7, n and m are as defined herein. Also disclosed herein are the methods of preparation of compounds of formula (I), intermediates therefor and their utility in treating a variety of disease conditions.