4BOH:
reference: The tick-derived anticoagulant madanin is processed by thrombin and factor xa., Figueiredo AC, de Sanctis D, Pereira PJ, PLoS One. 2013;8(8):e71866. doi: 10.1371/journal.pone.0071866. PMID: 23951260

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