A compound of formula wherein: n is 1 or 2; R which is in meta or para position, is C 3 -C 6 alkyl or benzyloxy, where the phenyl radical of the benzyloxy group is optionally substituted with fluoro or chloro; R 1 is hydrogen, methyl, chloro or fluoro; R 2 is hydrogen or C 1 -C 3 alkyl; R 3 is hydrogen or C 1 -C 4 alkyl optionally substituted by hydroxy or methoxy; R 4, R 5 are, independently, hydrogen or C 1 -C 4 alkyl; if the case, either as a single optically active isomer or a mixture thereof or a pharmaceutically acceptable salt thereof, for use in the prevention and treatment of a psychiatric disorder which is schizophrenia, a schizophrenia related disorder and/or an anxiety disorder, wherein the schizophrenia related disorder is selected from brief psychotic disorders, delusional disorders, schizoaffective disorder, and schizophreniform disorders, and the anxiety disorder is selected from panic disorders, obsessive-compulsive disorders, post-traumatic stress disorders, social phobia or social anxiety disorders, specific phobias, and generalized anxiety disorders; provided that a compound of formula selected from: 2-(4-Benzyloxybenzylamino)-propanamide; 2-[4-(2-Fluorobenzyloxy)-benzylamino]-propanamide; -(+)-2-[4-(2-Fluorobenzyloxy)-benzylamino]-propanamide -(-)-2-[4-(2-Fluorobenzyloxy)-benzylamino]-propanamide 2-[4-(2-Fluorobenzyloxy)-benzylamino]-N-methyl-propanamide; 2-[4-(3-Fluorob enzyloxy)-benzylamino]-propanamide; -(+)-2-[4-(3-Fluorobenzyloxy)-benzylamino]-propanamide; -(-)-2-[4-(3-Fluorobenzyloxy)-benzylamino]-propanamide; 2-[4-(3-Fluorobenzyloxy)-benzylamino-N-methyl-propanamide; 2-[4-(4-Fluorobenzyloxy)-benzylamino]-propanamide; 2-[4-(2-Chlorobenzyloxy)-benzylamino]-propanamide; -(+)-2-[4-(2-Chlorobenzyloxy)-benzylamino]-propanamide; -(-)-2-[4-(2-Chlorobenzyloxy)-benzylamino]-pxopanamide; 2-[4-(3-Chlorobenzyloxy)-benzylamino]-propanamide; -(+)-2-[4-(3-Chlorobenzyloxy)-benzylamino]-propanamide; -(-)-2-[4-(3-Chlorobenzyloxy)-benzylamino]-propanamide; 2-(4-Benzyloxybenzylamino)-3-hydroxy-propanamide; 2-[4-(2-Fluorobenzyloxy)-benzylamino]-3-hydroxy-propanamide; 2-[4-(3-Fluorobenzyloxy)-benzylamino]-3-hydroxy-propanamide; 2-(4-Benzyloxybenzylamino)-3-hydroxy-N-methyl-propanamide; 2-[4-(2-Fluorobenzyloxy)-benzylamino]-3-hydxoxy-N-methyl-propanamide; 2-[4-(3-Fluorobenzyloxy)-benzylamino]-3-bydroxy-N-methyl-propanamide; 2-[4-(2-Chlorobenzyloxy)-benzylamino]-3-hydroxy-N-methyl-propanamide; 2-[4-(2-Fluorobenzyloxy)-phenylethylamino]-propanamide; 2-[4-(3-Fluorobenzyloxy)-phenylethylamino]-propanamide; 2-[4-(2-Chlorobenzyloxy)-phenylethylamino]-propanamide; 2-[4-(3-Chlorobenzyloxy)-phenylethylamino]-propanamide 2-[N-(4-Benzyloxybenzyl)-N-methylamino]-propanamide; 2-(4-Benzyloxybenzylamino)-3-methyl-N-methyl-butanamide; or a pharmaceutically acceptable salt thereof, is not used for the treatment of schizophrenia and anxiety associated to cognitive impairment. n is 1 or 2; R which is in meta or para position, is C 3 -C 6 alkyl or benzyloxy, where the phenyl radical of the benzyloxy group is optionally substituted with fluoro or chloro; R 1 is hydrogen, methyl, chloro or fluoro; R 2 is hydrogen or C 1 -C 3 alkyl; R 3 is hydrogen or C 1 -C 4 alkyl optionally substituted by hydroxy or methoxy; R 4, R 5 are, independently, hydrogen or C 1 -C 4 alkyl; 2-(4-Benzyloxybenzylamino)-propanamide; 2-[4-(2-Fluorobenzyloxy)-benzylamino]-propanamide; -(+)-2-[4-(2-Fluorobenzyloxy)-benzylamino]-propanamide -(-)-2-[4-(2-Fluorobenzyloxy)-benzylamino]-propanamide 2-[4-(2-Fluorobenzyloxy)-benzylamino]-N-methyl-propanamide; 2-[4-(3-Fluorob enzyloxy)-benzylamino]-propanamide; -(+)-2-[4-(3-Fluorobenzyloxy)-benzylamino]-propanamide; -(-)-2-[4-(3-Fluorobenzyloxy)-benzylamino]-propanamide; 2-[4-(3-Fluorobenzyloxy)-benzylamino-N-methyl-propanamide; 2-[4-(4-Fluorobenzyloxy)-benzylamino]-propanamide; 2-[4-(2-Chlorobenzyloxy)-benzylamino]-propanamide; -(+)-2-[4-(2-Chlorobenzyloxy)-benzylamino]-propanamide; -(-)-2-[4-(2-Chlorobenzyloxy)-benzylamino]-pxopanamide; 2-[4-(3-Chlorobenzyloxy)-benzylamino]-propanamide; -(+)-2-[4-(3-Chlorobenzyloxy)-benzylamino]-propanamide; -(-)-2-[4-(3-Chlorobenzyloxy)-benzylamino]-propanamide; 2-(4-Benzyloxybenzylamino)-3-hydroxy-propanamide; 2-[4-(2-Fluorobenzyloxy)-benzylamino]-3-hydroxy-propanamide; 2-[4-(3-Fluorobenzyloxy)-benzylamino]-3-hydroxy-propanamide; 2-(4-Benzyloxybenzylamino)-3-hydroxy-N-methyl-propanamide; 2-[4-(2-Fluorobenzyloxy)-benzylamino]-3-hydxoxy-N-methyl-propanamide; 2-[4-(3-Fluorobenzyloxy)-benzylamino]-3-bydroxy-N-methyl-propanamide; 2-[4-(2-Chlorobenzyloxy)-benzylamino]-3-hydroxy-N-methyl-propanamide; 2-[4-(2-Fluorobenzyloxy)-phenylethylamino]-propanamide; 2-[4-(3-Fluorobenzyloxy)-phenylethylamino]-propanamide; 2-[4-(2-Chlorobenzyloxy)-phenylethylamino]-propanamide; 2-[4-(3-Chlorobenzyloxy)-phenylethylamino]-propanamide 2-[N-(4-Benzyloxybenzyl)-N-methylamino]-propanamide; 2-(4-Benzyloxybenzylamino)-3-methyl-N-methyl-butanamide;