The present invention relates to a compound of general formula (I) wherein R1 is hydrogen, lower alkyl, CD3, -(CH2)n-CHO, -(CH2)n-O-lower alkyl, -(CH2)n-OH, -(CH2)n-cycloalkyl or is heterocycloalkyl R2 is hydrogen, halogen, hydroxy, lower alkyl, di-lower alkyl, -OCH2-O-lower alkyl, or lower alkoxy or the piperidin ring form together with R2 a spiro ring, selected from 4-aza-spiro[2.5]oct-6-yl Ar is aryl or heteroaryl, which are optionally substituted by one, two or three substituents, selected from halogen, lower alkyl, lower alkyl substituted by halogen, lower alkoxy substituted by halogen, cycloalkyl, lower alkoxy, S-lower alkyl, heteroaryl, heterocycloalkyl, or by phenyl optionally substituted by R, and R is halogen, lower alkyl, lower alkoxy or lower alkoxy substituted by halogen, or is heteroaryl R is lower alkyl, cycloalkyl, heterocycloalkyl, aryl or heteroaryl, wherein aryl and heteroaryl are optionally substituted by one or two R n is 0, 1 2 or 3 or to a pharmaceutically acceptable acid addition salt, to a racemic mixture, or to its corresponding enantiomer and/or optical isomer thereof. Furthermore, the present invention relates to pharmaceutical compositions containing the compounds of formula I and to their use in the treatment of neurological and neuropsychiatric disorders.La présente invention concerne un composé de la formule générale (I) dans laquelle R1 est hydrogène, alkyle inférieur, CD3, -(CH2)n-CHO, -(CH2)n-O-alkyle inférieur, -(CH2)n-OH, -(CH2)n-cycloalkyle ou est hétérocycloalkyle R2 est hydrogène, halogène, hydroxy, alkyle inférieur, di(alkyle inférieur), -OCH2-O-alkyle inférieur ou alcoxy inférieur ou le noyau pipéridine forme conjointement avec R2 un noyau spiro, choisi parmi 4-azaspiro[2.5]oct-6-yle Ar est aryle ou hétéroaryle, qui est facultativement substitué par un, deux ou trois substituants, choisis parmi halogène, alkyle inférieur, alkyle inférieur substitué par halogène, alcoxy inférieur substitué par halogène, cycloalkyle, alcoxy
