The present invention relates to a compound of formula 1. or 2wherein R1 represents straight-chain or branched C2-C8 alkyl, C2-C8 alkenyl, optionally substituted by at least one substituent selected from the group consisting of hydroxyl, amino or C1-C6 alkyl amino group, or C2-C4 alkynyl, optionally substituted by at least one substituent selected from the group consisting of hydroxyl, amino or C1-C6 alkyl amino group and R2 represents hydroxyl, C1-C6 alkyl, C1-C6 alkylcarbonyl, di(C1-C6-alkyl)aminomethyl, C3-C6 heterocyclylmethyl or arylaminomethyl, wherein the aryl group is optionally substituted by at least one substituent selected from the group consisting of halogens and C1-C6 alkoxy as well as associated pharmaceutical compositions and uses of the compound or composition in therapy, in particular for the treatment of a disorder or a disease susceptible to inhibition of COX-2.