| abstract |
The present invention relates to compounds of formula (I) wherein R1/R2 are independently from each other hydrogen or lower alkyl; R3 is independently from the number of substituents hydrogen, halogen, lower alkyl, lower alkyl substituted by halogen, lower alkoxy or lower alkoxy substituted by halogen; R4 is halogen, lower alkyl, lower alkyl substituted by halogen, lower alkoxy or lower alkoxy substituted by halogen; hetaryl is a one or two membered heteroaromatic ring, connected to the carbon atoms of the piperidine group selected from the group consisting of (II), (II), (IV) or (V) or to pharmaceutically suitable acid addition salts, optically pure enantiomers, racemates or diastereomeric mixtures thereof. It has been found that the compounds of formula I are orexin receptor antagonists and the related compounds may be useful in the treatment of disorders, in which orexin pathways are involved like sleep disorders. |