The present invention relates to compounds of formula (I), wherein L is a bond, -C(O)NH-, -NHC(O)-, -CH2NHC(O)-, CH2C(O)NH-, -CH2NH-, -NH- or -NHC(O)NH-； R1 is hydrogen, lower alkyl, halogen, lower alkoxy-alkyl, lower alkoxy substituted by halogen, lower alkyl substituted by halogen or is phenyl or heteroaryl selected from the group consisting of pyridinyl, pyrimidinyl, pyrazinyl or pyrazolyl, and wherein phenyl and heteroaryl are optionally substituted by one, two or three substituents selected from the group consisting of halogen, lower alkyl, lower alkoxy, lower alkyl substituted by halogen, lower alkoxy substituted by halogen, cycloalkyl or O-CH2-cycloalkyl； or to a pharmaceutically suitable acid addition salt thereof, to 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.
