A potent, cell permeable and reversible inhibitor of β-secretase that corresponds to the β-secretase cleavage site (VNL-DA) of the Swedish mutant Amyloid Precursor Protein (APP). Inhibits the formation of both Aβtotal (IC₅₀ = 700 nM) and Aβ1-42 (IC₅₀ = 2.5 µM) in CHO cells stably transfected with wild-type APP751.