6DDY:
reference: Structure and Mechanisms of NT5C2 Mutations Driving Thiopurine Resistance in Relapsed Lymphoblastic Leukemia., Dieck CL, Tzoneva G, Forouhar F, Carpenter Z, Ambesi-Impiombato A, Sanchez-Martin M, Kirschner-Schwabe R, Lew S, Seetharaman J, Tong L, Ferrando AA, Cancer Cell. 2018 Jul 9;34(1):136-147.e6. doi: 10.1016/j.ccell.2018.06.003. PMID: 29990496

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