| abstract |
A compound of formula (I) or a salt thereof, or a solvate thereof, wherein either: (i) Ra represents a group R5 which is hydrogen, alkyl or optionally substituted aryl and Rb represents a moiety of formula (a); wherein X represents a hydroxy or an alkoxy group wherein the alkyl group may be substituted or unsubstituted or X represents a group NRsRt wherein Rs and Rt each independently represent hydrogen, alkyl, substituted alkyl, optionally substituted alkenyl, optionally substituted aryl, optionally substituted arylalkyl, an optionally substituted heterocyclic group or an optionally substituted heterocyclylalkyl group, or Rs and Rt together may form a heterocyclic group; R1 represents an alkyl or a substituted or unsubstituted aryl group; and R2, R3 and R4 each independently represent hydrogen, alkyl, aryl or substituted aryl or (ii) Ra represents a moiety of the above defined formula (a) and Rb represents the above defined R5; R6 and R7 each independently represents hydrogen, hydroxy, amino, alkoxy, optionally substituted aryloxy, optionally substituted benzyloxy, alkylamino, dialkylamino, halo, trifluoromethyl, trifluoromethoxy, nitro, alkyl, carboxy, carbalkoxy, carbamoyl, alkylcarbamoyl, or R6 and R7 together represent methylenedioxy, carbonyldioxy or carbonyldiamino; and R8 represents hydrogen, hydroxy, alkanoyl, alkyl, aminoalkyl, hydroxyalkyl, carboxyalkyl, carbalkoxyalkyl, carbamoyl or aminosulphonyl; a process for the preparation of such a compound, a pharmaceutical composition comprising such a compound and the use of such a compound in medicine. |