abstract |
Compounds of formula (I) or a salt thereof are provided: n n n n n n n n n n wherein R 4 , R 6 , R 7 , R 8 , Q, A, Y, n and R are as defined in the description. Use of the compounds for treating psychotic disorders, cognitive impairments and Alzheimer's Disease are disclosed. The invention further discloses pharmaceutical compositions comprising the compounds. |