1-Naphthalenesulfonyl-IW-CHO Off-white solid. A potent, cell-permeable, selective, and reversible inhibitor of cathepsin L (IC50 = 1.9 nM). Also inhibits the release of Ca2+ and hydroxyproline from bone in an in vitro bone culture system and prevents bone loss in ovariectomized mice (~50 mg/kg). Purity: ≥98% by HPLC. 1-Naphthalenesulfonyl-Ile-Trp-CHO Ref.: Yasuma, T., et al. 1998. J. Med. Chem. 41, 4301. | 
