4KB9:
reference: Highly Potent HIV-1 Protease Inhibitors with Novel Tricyclic P2 Ligands: Design, Synthesis, and Protein-Ligand X-ray Studies., Ghosh AK, Parham GL, Martyr CD, Nyalapatla PR, Osswald HL, Agniswamy J, Wang YF, Amano M, Weber IT, Mitsuya H, J Med Chem. 2013 Aug 15. PMID: 23947685

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