| abstract |
Compounds of general formula (1), wherein Y is a halogen atom or a group -OR1 where R1 is an optionally substituted alkyl group; X is -O-, -S- or -N(R8)-, where R8 is a hydrogen atom or an alkyl group; R2 is an optionally substituted alkyl, alkenyl, cycloalkyl or cycloalkenyl group; R3 is a hydrogen or halogen atom or an -OR9 group, where R9 is a hydrogen atom or an optionally substituted alkyl, alkenyl, alkoxyalkyl, or alkanoyl group, or a formyl, carboxamido or thiocarboxamido group; R4 is a group -(CH¿2?)nAr, where Ar is a monocyclic or bicyclic aryl group optionally containing one or more heteratoms selected from oxygen, sulphur or nitrogen atoms and n is zero or an integer 1, 2 or 3; R?5¿ is a C¿3-9?carbocyclic ketone optionally containing one or more heteratoms selected from oxygen, sulphur or nitrogen atoms; R?6¿ is a hydrogen atom or an optionally substituted alkyl group; R7 is a hydrogen atom or an optionally substituted alkyl group; and the salts, solvates, hydrates and N-oxides thereof. Compounds according to the invention are potent and selective phosphodiesterase type IV inhibitors and are useful in the prophylaxis and treatment of diseases such as asthma where an unwanted inflammatory response or muscular spasm is present. |