2ZIO:
reference: Multistep Engineering of Pyrrolysyl-tRNA Synthetase to Genetically Encode N(varepsilon)-(o-Azidobenzyloxycarbonyl) lysine for Site-Specific Protein Modification., Yanagisawa T, Ishii R, Fukunaga R, Kobayashi T, Sakamoto K, Yokoyama S, Chem Biol. 2008 Nov;15(11):1187-97. PMID: 19022179

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).