2QS1:
reference: Binding site and ligand flexibility revealed by high resolution crystal structures of GluK1 competitive antagonists., Alushin GM, Jane D, Mayer ML, Neuropharmacology. 2011 Jan;60(1):126-34. Epub 2010 Jun 15. PMID: 20558186

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