A compound of formula (I): ##STR00001## and pharmaceutically acceptable derivatives thereof, wherein R.sup.1 is H or C.sub.1-6alkyl; R.sup.2 is ##STR00002## wherein ##STR00003## defines the point of attachment of the ring; and R.sup.3 is C.sub.1-6alkyl or NH.sub.2. Compounds of formula (I) are potent and selective inhibitors of COX-2 and are of use in the treatment of pain, fever, inflammation of a variety of conditions and diseases.