6ZTE:
reference: Quadruplex-Duplex Junction: A High-Affinity Binding Site for Indoloquinoline Ligands., Vianney YM, Preckwinkel P, Mohr S, Weisz K, Chemistry. 2020 Sep 25. doi: 10.1002/chem.202003540. PMID: 32975874

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