This invention relates to compounds of formula (I) ##STR00001## and to pharmaceutically acceptable salts and solvates thereof, wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, W, X, Y, and Ar are as defined herein. Compounds of formula (I) are useful in the treatment of diseases or conditions characterized by cellular hyperproliferation. This invention also relates to means for the preparation of compounds of formula (I); formulations containing compounds of formula (I); and methods for the use of said compounds and formulations in the treatment of a disease or condition characterized by cellular hyperproliferation, including cancer.