Provided are excellent β-
secretase inhibitors, that is, compounds represented by the general formula (1) or prodrugs thereof:wherein A is amino or protected amino; B1 and B2 are each a
single bond, alkylene of 1 to 3 carbon atoms, or the like; D is a
single bond, —NHCO, or the like; E is —COOH,
tetrazole ring, or the like; n is an integer of 1 to 3; m is an integer of 1 to 3; G is hydroxyl, a group represented by the general formula (2), or the like:in which Z is —NH, -Asp-Ala-NH—, -Asp-Ala-, -Asp-NH—, or the like; L is a 5-to 10-membered ring optionally containing a
heteroatom and / or unsaturated bond; X is —COOH,
tetrazole ring, or the like; Y is
hydrogen, —COOH, or the like; and k is an integer of 1 to 4; and R1, R2, and R3 are each
alkyl of 1 to 6 carbon atoms, or the like.