Fig. 4: X-ray crystal structure of peptide [6]catenane 6.
a Cartoon loop representation of 6 viewed along the C3 axis. b The six equivalent C4-propeller-shaped Ag4(5)4 macrocycle components of 6 are disassembled and shown individually. c A three-way junction structure in 6, which corresponds to a vertex of the T2-hexahedral link topology. d A T2-twist structure in 6, which corresponds to an edge of the topology. The white balls indicate Ag+. e Schematic diagram of the [6]catenane framework topology. The arrows on each ring indicate the N→x→C direction of the peptide ligand. f Space-filling representation of 6 showing the closed-shell exterior. g Cross-sectional view of the surface representation of 6. In all figures, anions are omitted for clarity and topologically-linked macrocycles are individually colour-coded.
