Disclosed are compounds of formula (I) wherein R1, R2, R3, R4 and R5 are H； R6 is methoxymethyl； A7 is C-R7, A8 is N and A9 is C-R9； R7, R9, R10 and R11 are selected independently of each other from H, C1-6alkyl, C2-6alkenyl, C2-6alkynyl, C1-6alkoxy and OR12； wherein R12 represents a monocyclic saturated ring moiety having 4-6 ring atoms wherein one of said ring atoms is O and the rest is C； and pharmaceutically acceptable salts thereof, which are positive allosteric modulators (PAMs) of the nicotinic acetylcholine &alpha；7 receptor and are therefore useful in the treatment of conditions including schizophrenia, psychosis and other cognitive disorders. Compounds of formula I include (1S,2S)-2-phenyl-cyclopropanecarboxylic acid[(R)-1-(6-ethoxy-pyridin-3-yl)-2-methoxyethyl]-amide； (1S,2S)-N-[(1R)-2-methoxy-1-[6-[(3R)-tetrahydrofuran-3-yl]oxy-3-pyridyl]ethyl]-2-phenylcyclopropanecarboxamide； (1S,2S)-N-[(1R)-2-methoxy-1-[6-[(3S)-tetrahydrofuran-3-yl]oxy-3-pyridyl]ethyl]-2-phenylcyclopropanecarboxamide； and (1S,2S)-2-phenyl-cyclopropanecarboxylic acid { (R)-2-methoxy-1-[6-(tetrahydro-pyran-4-yloxy)-pyridin-3-yl]-ethyl} -amide.
