| abstract |
A compound of formula (I):n or a salt and/or solvate thereof, whereinn R represents an acyl group containing a substituted or unsubstituted carbocyclic aromatic or heterocyclic aromatic group; R 1 and R 2 each independently represents an alkyl, alkenyl or alkynyl group or R 1 together with R 2 represents a C 3-6 polymethylene or alkenylene group; R 3 represents hydrogen or alkyl; R 4 represents hydrogen, halogen, alkyl, hydroxy, alkoxy, nitrile, nitro, amino or mono or disubstituted amino; and n represents O or an integer 1, is useful in the treatment of pain. |