3EBS:
reference: Key Residues Controlling Phenacetin Metabolism by Human Cytochrome P450 2A Enzymes., Devore NM, Smith BD, Urban MJ, Scott EE, Drug Metab Dispos. 2008 Sep 8. PMID: 18779312

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