ALPHA-KETOAMIDE DERIVATIVES AS CATHEPSIN L INHIBITOR

摘要

The present invention relates to a cathepsin L inhibitor comprising a compound of general formula (Ia), wherein Q represents a direct bond or 1 or 2 amino acid residues that may be substituted; R<1> represents a hydrogen atom or a hydrocarbon group or heterocyclic group that may be substituted; R<4> represents an acyl group or a carboxyl group that may be esterified and R<5> and R<6> independently represent a hydrogen atom or a hydrocarbon group or heterocyclic group that may be substituted or R<5> and R<6> may bind together to form a ring; or a salt thereof, which has strong bone resorption-suppressing action and is useful for preventing or treating osteoporosis.