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, R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, 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.