5UHR:
reference: A Tetramer Derived from Islet Amyloid Polypeptide., Wang Y, Kreutzer AG, Truex NL, Nowick JS, J Org Chem. 2017 Aug 4;82(15):7905-7912. doi: 10.1021/acs.joc.7b01116. Epub 2017 , Jul 14. PMID: 28661686

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