Disclosed are compounds of the formula I or a stereoisomer, tautomer, or pharmaceutically acceptable salt or solvate thereof, wherein Q is a bond or —N(R5)—; T is a bond, —O—, —C(O)—; S, —N(R5)—, or —C(R6′R7′); U is a bond or —C(R6)(R7)— Y is C or N; Z is C or N; ring A, including variables Y and Z, is a three to nine membered cycloalkyl, cycloalkenyl, heterocyclyl, heterocyclenyl, aryl, and heteroaryl ring having 0 to 4, preferably 0 to 2, heteroatoms independently selected from the group consisting of O, S, N and —N(R)—, wherein ring A is unsubstituted or substituted with 1 to 5 independently selected R1 moieties and/or oxo when ring A is cycloalkyl, cycloalkenyl, heterocyclyl or heterocyclenyl; and R, R1, R2, R3, R4, R5, R6, R6, R7 and R7′ are as defined in the specification; pharmaceutical compositions comprising the compounds of formula I and the method of inhibiting aspartyl protease, and in particular, the methods of treating cardiovascular diseases, cognitive and neurodegenerative diseases.