5OB6:
reference: Ru-Based CO releasing molecules with azole ligands: interaction with proteins and the CO release mechanism disclosed by X-ray crystallography., Pontillo N, Ferraro G, Messori L, Tamasi G, Merlino A, Dalton Trans. 2017 Jul 25;46(29):9621-9629. doi: 10.1039/c7dt01991b. PMID: 28702564

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