A compound of the formula
1
wherein a, T, V, X, Y, Z, R
1
, R
2
, R
3
, R
4
, R
5
, R
6
, R
7
, R
8
and R
9
are as defined above, their pharmaceutically acceptable salts and pharmaceutical compositions containing such compounds or their salts.
该化合物的
化学式为1,其中a,T,V,X,Y,Z,R1,R2,R3,R4,R5,R6,R7,R8和R9的定义如上所述,其药学上可接受的盐和含有这种化合物或其盐的制药组合物。