Compounds of formula (I) or a derivative thereof:
wherein A, B, Z, R
1
, R
2a
, R
2b
, R
x
, R
6
, and R
9
are as defined in the specification, a process for the preparation of such compounds, pharmaceutical compositions comprising such compounds and the use of such compounds in medicine.
Compounds of formula (I) or a derivative thereof: wherein A, B, Z, R1, R2a, R2b, Rx, R8, and R9 are as defined in the specification, a process for the preparation of such compounds, pharmaceutical compositions comprising such compounds and the use of such compounds in medicine.