| abstract |
A compound which is a 5,6-dihydro-a-pyrone of formula (I): wherein bond a is oriented either or X is O or NH; R<SP>1</SP> is selected from - a group R<SP>3</SP>(O)C- wherein R<SP>3</SP> is either (i) a group of formula R<SP>4</SP>-CH=CH- wherein R<SP>4</SP> is C 1 -C 20 alkyl, C 2 -C 20 alkenyl, an aryl group, or a 5- or 6-membered unsaturated heterocyclic ring containing one or two O, N or S atoms, (ii) C 2 -C 20 alkyl, or (iii) an aryl group or a fused ring substituent of formula (1) or (2): wherein each of R' and R", which are the same or different and may occupy any position of ring a or ring b of the fused ring system, is H or C 1 -C 6 alkyl; - a group ArCH 2 - wherein Ar is an aryl group; and - a group R<SP>5</SP>O-CH 2 - wherein R<SP>5</SP> is C 1 -C 6 alkyl optionally interrupted by one or two O atoms; and R<SP>2</SP> is CH 3 or, when R<SP>1</SP> is a group of formula (A) as defined below, R<SP>2</SP> is R<SP>6</SP>OOC- or R<SP>6</SP>NOC- wherein R<SP>6</SP> is C 1 -C 6 alkyl; or a pharmaceutically or veterinarily acceptable salt or ester thereof has activity as an inhibitor of cytokine production. A process for producing the compounds and pharmaceutical compositions containing them are also disclosed. |