A compound of formula (I) or a pharmaceutically acceptable derivative thereof,
wherein, R1 R2 R3, R4, R5, R6, X and Y are as defined in the specification; a process for preparing such compounds; a pharmaceutical composition comprising such compounds; and the use of such compounds in medicine.
式(I)的化合物或其药学上可接受的衍
生物,其中R1、R2、R3、R4、R5、R6、X和Y的定义如规范中所述;制备这种化合物的方法;包含这种化合物的药物组合物;以及这种化合物在医学上的用途。