2E74:
reference: Structure of the Cytochrome b(6)f Complex: Quinone Analogue Inhibitors as Ligands of Heme c(n)., Yamashita E, Zhang H, Cramer WA, J Mol Biol. 2007 Jun 29;370(1):39-52. Epub 2007 Apr 12. PMID: 17498743

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