The present invention relates to compounds of formula (I) or pharmaceutically acceptable salts thereof, wherein A, L, D, R1-R15, w, x, y, and z are defined herein. The novel cycloalkyl-linked diheterocycle derivatives that are useful in the treatment of abnormal cell growth, such as cancer, in mammals. The present invention also relates to pharmaceutical compositions containing the compounds and to methods of using the compounds and compositions in the treatment of abnormal cell growth in mammals.