There are provided compounds of the formula
wherein X, Y, Z, R1, R2, R3 and R4 are as described herein
and enantiomers and pharmaceutically acceptable salts and esters thereof. The compounds are useful as anticancer agents.
There are provided compounds of formula (I) wherein X, Y, Z, R1, R2, R3 and R4 are as described herein, and enantiomers and pharmaceutically acceptable salts and esters thereof; as well as methods for making such compounds, pharmaceutical compositions comprising said compounds, and their use in the treatment of cancer.