The present invention relates to compounds of formula wherein R1, R2, R3, and n are as described in the specification and pharmaceutically acceptable acid addition salts thereof. The compounds of formula I can be used for the treatment of 5-HT5A receptor antagonists related diseases, which include depression, anxiety disorders, schizophrenia, panic disorders, agoraphobia, social phobia, obsessive compulsive disorders, post-traumatic stress disorders, pain, memory disorders, disorders of eating behaviors, sexual dysfunction, sleep disorders, withdrawal from abuse of drugs, motor disorders such as Parkinson's disease, dementia in Parkinson's disease, neuroleptic-induced Parkinsonism and tardive dyskinesias, as well as other psychiatric disorders and gastrointestinal disorders such as irritable bowel syndrome.