| abstract |
ABSTRACT Compounds of the formula: wherein R1 is hydrogen, halogen, hydroxy, lower alkoxy, lower alkyl or mono(or di or tri)halo(lower)-alkyl, and is , , , , or (in which R2 and R3 are each lower alkyl), and pharmaceutically acceptable salts thereof. These compounds have an acetylcholinesterase-inhibitory activity. Processes for the production of these compounds, pharmaceutical composition containing them and the use thereof for the manufacture of medicaments and for the therapeutic treatment of disorders of the central nervous system such as amnesia, dementia or the like are also disclosed. |