abstract |
The present invention provides compounds of formula I n n n and pharmaceutically acceptable salts, wherein R1, R2, R3, R4, R5, X and Y have the meanings defined in the specification. The compounds have histone deacetylase (HDAC) inhibitory activity which is useful in cancer treatment. Also provided is a process for making a compound of formula I n by reacting a compound of formula III n n n with a compound of formula IV n n n wherein n A is a displaceable group and PG is a protecting group. |