| abstract |
ABSTRACT The invention relates to compounds of formula I (I) [wherein R1, R2, R3 and R4, which may be the same or different, each represents a hydrogen or halogen atom or a C1 to C6 alkyl or C1 to C6 alkoxy group; R5 and R6, which may be the same or different, each represents a hydrogen atom or a C1 to C6 alkyl or C3 to C6 alkenyl group; or R5 and R6, together with the nitrogen atom to which they are attached, represent a pyrrolidino, piperidino or morpholino group; and X represents an oxygen or sulfur atom or a methylene group] and the tautomeric forms (where R6 represents a hydrogen atom) of formula Ia (Ia) as well as to acid adition salts of compounds of formulae I and Ia and processes for their preparation. The compounds of formulae I and Ia and their physiolo-gically acceptable acid addition salts possess anti-allergic, antihistaminic and antiserotonic activity and the invention also releates to pharmaceutical preparations containing these compounds or salts. |