| abstract |
The present invention relates to compounds of Formula (I), wherein Ar is an unsubstituted or substituted aryl or heteroaryl group, wherein the aryl and the heteroaryl group may be substituted by one or more substituents R2; R2 is hydroxy, halogen, lower alkyl, lower alkyl substituted by halogen, lower alkoxy, lower alkoxy substituted by halogen, C(O)-lower alkyl, nitro, NR,R,,, cyano, S-lower alkyl, SO2-lower alkyl, cycloalkyl, heterocycloalkyl, phenyloxy, benzyloxy, phenyl, NH-phenyl or heteroaryl, wherein the phenyl and heteroaryl group is unsubstituted or substituted by one or more substituents selected from lower alkyl or halogen; R,/R,, are independently from each other hydrogen or lower alkyl; R1 is hydrogen or lower alkyl; Het is a heteroaryl group, unsubstituted or substituted by one or more substituents selected from R3; R3 is hydroxy, halogen, =O, lower alkyl, lower alkyl substituted by halogen, lower alkoxy, phenyl, lower alkoxy substituted by halogen, nitro, cyano, SO2-lower alkyl, cycloalkyl or heterocycloalkyl; n is 1 or 2; 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 sleep apnea, narcolepsy, insomnia, parasomnia, jet lag syndrome, circadian rhythms disorder or sleep disorders associated with neurological diseases. |