This invention relates to compounds of formula Itheir use as inhibitors of the microsomal prostaglandin E2 synthase-1 (mPGES-1), to pharmaceutical compositions containing them, and their use as medicaments for the treatment and/or prevention of inflammatory diseases and associated conditions. A, M, W, R1, R2, R3, R4, R6, R2, R7, R8, R9, Ra, Rb have meanings given in the description.