Compounds of the formula (I), in which R1, R2′, R2″, R2′″, R3 and n are as defined in Claim 1, are effectors of the nicotinic and/or muscarinic acetylcholine receptor and are suitable for the prophylaxis or treatment of schizophrenia, depression, anxiety states, dementia, Alzheimer's disease, Lewy bodies dementia, neurodegenerative diseases, Parkinson's disease, Huntington's disease, Tourette's syndrome, learning and memory impairments, age-related memory impairment, amelioration of withdrawal symptoms in nicotine dependence, strokes or brain damage by toxic compounds.