3VB6:
reference: Design, synthesis and crystallographic analysis of nitrile-based broad-spectrum peptidomimetic inhibitors for coronavirus 3C-like proteases., Chuck CP, Chen C, Ke Z, Chi-Cheong Wan D, Chow HF, Wong KB, Eur J Med Chem. 2012 Nov 7;59C:1-6. doi: 10.1016/j.ejmech.2012.10.053. PMID: 23202846

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