1HPS:
reference: Rational design, synthesis, and crystallographic analysis of a hydroxyethylene-based HIV-1 protease inhibitor containing a heterocyclic P1'--P2' amide bond isostere., Thompson SK, Murthy KH, Zhao B, Winborne E, Green DW, Fisher SM, DesJarlais RL, Tomaszek TA Jr, Meek TD, Gleason JG, et al., J Med Chem 1994 Sep 16;37(19):3100-7. PMID: 7932533

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