There are provided compounds of the formula
or a pharmaceutically acceptable salt or ester thereof wherein X, Y, R
1
, R
2
are as herein described.
The compounds have utility as antiproliferative agents, especially, as anticancer agents.
There are provided compounds of the general formulas
wherein X, Y, R
1
, R
2
, R
3
and R
4
are as described herein. The compounds exhibit anticancer activity.
There are provided compounds of the formula
or a pharmaceutically acceptable salt or ester thereof wherein X, Y, R1, R2 are as herein described.
The compounds have utility as antiproliferative agents, especially, as anticancer agents.