1C4Y:
reference: Structure of thrombin complexed with selective non-electrophilic inhibitors having cyclohexyl moieties at P1., Krishnan R, Mochalkin I, Arni R, Tulinsky A, Acta Crystallogr D Biol Crystallogr 2000 Mar;56 ( Pt 3):294-303. PMID: 10713516

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