4ROM:
reference: Identification of a novel class of covalent modifiers of hemoglobin as potential antisickling agents., Omar AM, Mahran MA, Ghatge MS, Chowdhury N, Bamane FH, El-Araby ME, Abdulmalik O, Safo MK, Org Biomol Chem. 2015 May 27;13(22):6353-70. doi: 10.1039/c5ob00367a. PMID: 25974708

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