Fig. 6

Structural origins of the molecular entanglements observed in [4]12-catenanes. a T2-edge geometry induced by interlocked Ω-shaped loops of 1 extracted from the crystal structure of [4]12-catenane 216. b Three-crossed geometry induced by the PII-helical conformation of 3 observed in the crystal structure of [4]12-catenane 4. Peptide regions are highlighted as cartoon representations. Hydrogen atoms, counter anions, and solvents have been omitted for clarity