1AAQ:
reference: Hydroxyethylene isostere inhibitors of human immunodeficiency virus-1 protease: structure-activity analysis using enzyme kinetics, X-ray crystallography, and infected T-cell assays., Dreyer GB, Lambert DM, Meek TD, Carr TJ, Tomaszek TA Jr, Fernandez AV, Bartus H, Cacciavillani E, Hassell AM, Minnich M, et al., Biochemistry 1992 Jul 28;31(29):6646-59. PMID: 1637805

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