The invention relates to compounds represented by Formula (I): ##STR00001## and to prodrugs thereof, pharmaceutically acceptable salts or solvates of said compounds or said prodrugs, wherein each of X.sup.1 X.sup.5 and R.sup.1 R.sup.5 are defined herein. The invention also relates to pharmaceutical compositions containing the compounds of Formula (I) and to methods of treating hyperproliferative disorders in a mammal by administering compounds of Formula (I).