6QBS:
reference: The Alkyne Moiety as a Latent Electrophile in Irreversible Covalent Small Molecule Inhibitors of Cathepsin K., Mons E, Jansen IDC, Loboda J, van Doodewaerd BR, Hermans J, Verdoes M, van Boeckel CAA, van Veelen PA, Turk B, Turk D, Ovaa H, J Am Chem Soc. 2019 Feb 27;141(8):3507-3514. doi: 10.1021/jacs.8b11027. Epub 2019, Feb 14. PMID: 30689386

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