The present invention relates to a compound of formula (I), wherein L is –C(O)NH-, -NHC(O)-, -S(O)2NH-, -NH- or -NHC(O)NH-; Ar is phenyl, benzyl, naphthyl or heteroaryl, selected from the group consisting of pyridinyl, pyrazolyl, pyrimidinyl, isoxazolyl or pyrazinyl, wherein Ar may be optionally substituted by one, two or three R1; R1 is hydrogen, lower alkyl, lower alkoxy, halogen, cyano, cycloalkyl, NHC(O)-lower alkyl, lower alkoxy substituted by halogen, lower alkyl substituted by halogen, or is phenyl optionally substituted by one or two halogen atoms, CF3O or lower alkyl, or is furanyl, thiazolyl or thiophenyl, optionally substituted by halogen or lower alkyl; X is CH or O; R is hydrogen or halogen; or a pharmaceutically suitable acid addition salt thereof, all racemic mixtures, all their corresponding enantiomers and/or optical isomers, which may be used for the treatment of depression, anxiety disorders, bipolar disorder, attention deficit hyperactivity disorder (ADHD), stress-related disorders, psychotic disorders, schizophrenia, neurological diseases, Parkinson's disease, neurodegenerative disorders, Alzheimer's disease, epilepsy, migraine, hypertension, substance abuse, metabolic disorders, eating disorders, diabetes, diabetic complications, obesity, dyslipidemia, disorders of energy consumption and assimilation, disorders and malfunction of body temperature homeostasis, disorders of sleep and circadian rhythm, and cardiovascular disorders.