| abstract |
There is provided cyclic amidine compounds of the following formula (I): n n n wherein: n A 1 and A 2 are hydrogen atom, optionally substituted alkyl group; optionally substituted aryl group; or optionally substituted heterocyclic group; and n X is —C(R 1 ,R 2 )—C(R 3 ,R 4 )—, —C(R 5 )═C(R 6 )—, —C(R 7 ,R 8 )—C(R 9 ,R 10 )—C(R 11 ,R 12 )—, or —C(R 13 ,R 14 )—C(R 15 ,R 16 )—NH— (wherein, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 and R 16 are hydrogen atom; halogen atom; optionally substituted alkyl group; optionally substituted aryl group; or optionally substituted heterocyclic group; n or pharmaceutically acceptable salts thereof. n These compounds have good affinity for α4β2 nicotinic acetylcholine receptors and activate the same to thereby exert a preventive or therapeutic effect on cerebral dysfunction. |