2WTJ:
reference: Identification and characterisation of 2-aminopyridine inhibitors of checkpoint kinase 2., Hilton S, Naud S, Caldwell JJ, Boxall K, Burns S, Anderson VE, Antoni L, Allen CE, Pearl LH, Oliver AW, Wynne Aherne G, Garrett MD, Collins I, Bioorg Med Chem. 2009 Dec 6. PMID: 20022510

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