There are provided compounds of Formula (I) wherein three of A
1
, A
2
, A
3
, and A
4
represent CH and one of A
1
, A
2
, A
3
, and A
4
represents CR
1
; R
1
represents SO
2
R2 or NHCOR2 wherein R2 represents C
1
-C
6
alkyl optionally substituted by one or more halogen, hydroxyl or alkoxy groups; R
9
represents C
6
-C
10
aryl; or a pharmaceutically acceptable salt thereof.