2Z9K:
reference: Structural basis of mercury- and zinc-conjugated complexes as SARS-CoV 3C-like protease inhibitors., Lee CC, Kuo CJ, Hsu MF, Liang PH, Fang JM, Shie JJ, Wang AH, FEBS Lett. 2007 Nov 27;581(28):5454-5458. Epub 2007 Nov 5. PMID: 17981158

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