2OP3:
reference: Characterization and Optimization of Selective, Nonpeptidic Inhibitors of Cathepsin S with an Unprecedented Binding Mode., Inagaki H, Tsuruoka H, Hornsby M, Lesley SA, Spraggon G, Ellman JA, J Med Chem. 2007 May 1;. PMID: 17469812

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).