| abstract |
Derivatives having the formula: <IMAGE> (I) where R1 denotes C1-C4 alkyl; X denotes oxygen or methylene; R2 denotes C1-C4 alkyl or CF3; R3 denotes a CH2R4 group in which R4 is (i) a pentagonal or hexagonal aromatic heterocyclic group comprising one or two nitrogen atoms and optionally fused with a benzene ring or (ii) a group having the formula <IMAGE> where n=0 or 1, and R5 and R6 independently denote C1-C4 alkyl or benzyl, and R5 and R6 also, together with the nitrogen atom to which they are bonded, form a piperidino or pyrrolidino or morpholino or N-methyl piperazino radical, and their N-oxide forms and acid addition salts of these derivatives and their N-oxide forms, the derivatives being in various stereoisomeric forms or in the form of a mixture of these forms, including the racemic form. |