5AZR:
reference: Crystal Structures and Coordination Behavior of Aqua- and Cyano-Co(III) Tetradehydrocorrins in the Heme Pocket of Myoglobin., Morita Y, Oohora K, Mizohata E, Sawada A, Kamachi T, Yoshizawa K, Inoue T, Hayashi T, Inorg Chem. 2016 Feb 1;55(3):1287-95. doi: 10.1021/acs.inorgchem.5b02598. Epub, 2016 Jan 13. PMID: 26760442

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