2JE4:
reference: Modular Total Chemical Synthesis of a Human Immunodeficiency Virus Type 1 Protease., Johnson EC, Malito E, Shen Y, Rich D, Tang WJ, Kent SB, J Am Chem Soc. 2007 Sep 19;129(37):11480-11490. Epub 2007 Aug 18. PMID: 17705484

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