Abstract: The present invention encompasses compounds of Formula I or pharmaceutically acceptable salts thereof, wherein each R1 may be substituted at any substitutable position on A and each R1 is independently selected from the group consisting of: halo, cyano, C1-4alkoxy, C1-4alkylthio and C1-4alkyl, each of said C1-4alkoxy, C1-4alkylthio and C1-4alkyl optionally substituted with 1 to 3 halo groups, R2 is selected from the group consisting of: C1-6alkyl and C3-6cycloalkyl, R3 is selected from the group consisting of: hydrogen, C1-6alkyl and C3-6cycloalkyl and R4 is a nitric oxide releasing moiety. Pharmaceutical composition comprising said compounds and methods of using said compounds are also encompassed. The compounds of the present invention lower the level of A?42 and are therefore useful for treating or preventing Alzheimer's Disease. The compounds of the invention also release nitric oxide in vivo and have a reduced potency for cyclooxygenase activity.