4CPQ:
reference: Synthesis of P1'-functionalized macrocyclic transition-state mimicking HIV-1 protease inhibitors encompassing a tertiary alcohol., De Rosa M, Unge J, Motwani HV, Rosenquist A, Vrang L, Wallberg H, Larhed M, J Med Chem. 2014 Aug 14;57(15):6444-57. doi: 10.1021/jm500434q. Epub 2014 Aug 1. PMID: 25054811

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