There is provided compounds of formula I, wherein ring A, D
1
, D
2a
, D
2b
, D
3
, L
1
, Y
1
, L
3
and Y
3
have meanings given in the description, and pharmaceutically-acceptable salts thereof, which compounds are useful in the treatment of diseases in which inhibition of leukotriene C
4
synthase is desired and/or required, and particularly in the treatment of a respiratory disorder and/or inflammation.