摘要 |
The invention relates to a process for the preparation of a compound of general formula (I) <IMAGE> (I) wherein R1 represents a hydrogen atom or a C1-10 alkyl, C3-7 cycloalkyl, C3-7 cycloalkyl-(C1-4)alkyl, C3-6 alkenyl, C3-10 alkynyl, phenyl or phenyl-(C1-3)alkyl group, and one of the groups represented by R2, R3 and R4 is a hydrogen atom or a C1-6 alkyl, C3-7 cycloalkyl, C2-6 alkenyl or phenyl-(C1-3)alkyl group and each of the other two groups, which may be the same or different, represent a hydrogen atom or a C1-6 alkyl group; or a salt or protected derivative thereof, by cyclization of a compound of general formula (II) <IMAGE> (II) wherein R1, R2, R3 and R4 are as defined above, or a salt or a protected derivative thereof. The compounds of formula (I) are potent and selective antagonists at "neuronal" 5-hydroxytryptamine receptors. |