3ZNH:
reference: On Terminal Alkynes That Can React with Active-Site Cysteine Nucleophiles in Proteases., Ekkebus R, van Kasteren SI, Kulathu Y, Scholten A, Berlin I, Geurink PP, de Jong A, Goerdayal S, Neefjes J, Heck AJ, Komander D, Ovaa H, J Am Chem Soc. 2013 Feb 15. PMID: 23387960

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