The invention provides compounds of formula (I): wherein R
1
and R
2
are as defined in the specification; processes for their preparation; pharmaceutical compositions containing them; a process for preparing the pharmaceutical compositions; and their use in therapy.
The invention provides compounds of formula (I): wherein R1 and R2 are as defined in the specification; processes for their preparation; pharmaceutical compositions containing them; a process for preparing the pharmaceutical compositions; and their use in therapy.