| abstract |
A compound of formula (I) or a salt thereof, wherein: P represents phenyl, a quinoline or isoquinoline residue, or a 5-membered or 6-membered aromatic heterocyclic ring containing up to three heteroatoms selected from nitrogen, oxygen or sulphur; R1 is hydrogen, C¿1-6? alkyl, halogen, CF3, NR?7R8 or OR9¿ where R?7, R8 and R9¿ are independently hydrogen, C¿1-6? alkyl or arylC1-6alkyl; R?2¿ is hydrogen or C¿1-6? alkyl; R?3¿ is C¿1-6? alkyl; n is 0 to 3; m is 0 to 4; and R?4¿ groups are independently C¿1-6? alkyl optionally substituted by one or more halogen atoms, C2-6 alkenyl, C2-6 alkynyl, C3-6 cycloalkyl, C3-6 cycloalkylC1-6 alkyl, C1-6 alkylthio, C3-6cycloalkylthio, C3-6 cycloalkylC1-6 alkylthio, halogen, nitro, CF3, OCF3, SCF3, SO2CF3, SO2F, formyl, C2-6 alkanoyl, cyano, optionally substituted phenyl or thienyl, NR?7R8, CONR7R8, or OR9¿ where R?7, R8 and R9¿ are as defined for R1, CO2R10 where R10 is hydrogen or C¿1-6? alkyl. The compounds have 5HT2C receptor antagonist activity. Certain compounds of the invention also exhibit 5HT2B antagonist activity. 5HT2C/2B receptor antagonists are believed to be of potential use in the treatment of CNS disorders. |