“Helix‐in‐Helix” Superstructure Formation through Encapsulation of Fullerene‐Bound Helical Peptides within a Helical Poly(methyl methacrylate) Cavity

• Published in: Angewandte Chemie International Edition Vol. 56; no. 3; pp. 791 - 795
• Main Authors: Ousaka, Naoki, Mamiya, Fumihiko, Iwata, Yoshiaki, Nishimura, Katsuyuki, Yashima, Eiji
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 16.01.2017; Wiley Subscription Services, Inc; John Wiley and Sons Inc
• Edition: International ed. in English
• Subjects: Buckminsterfullerene; Chemistry; Chemistry, Multidisciplinary; chirality; Communication; Communications; Conformation; Encapsulation; Fullerenes; Fullerenes - chemistry; Handedness; helical structures; Inclusion complexes; Macromolecular Substances - chemical synthesis; Macromolecular Substances - chemistry; Molecular Structure; Optical activity; Peptides; Peptides - chemical synthesis; Peptides - chemistry; Physical Sciences; Polymers; Polymethyl methacrylate; Polymethyl Methacrylate - chemistry; Polymethylmethacrylate; Science & Technology; Superstructures; supramolecular chemistry; POLYMERS; chirality; helical structures; INCLUSION COMPLEXES; peptides; fullerenes; CONFORMATION; ASSEMBLIES; MEMORY; FOLDAMERS; NANOTUBES; CHIRAL AMPLIFICATION; C-60; supramolecular chemistry
• DOI: 10.1002/anie.201611349
• ISSN: 1433-7851

A one‐handed 310‐helical hexapeptide is efficiently encapsulated within the helical cavity of st‐PMMA when a fullerene (C60) derivative is introduced at the C‐terminal end of the peptide. The encapsulation is accompanied by induction of a preferred‐handed helical conformation in the st‐PMMA backbone with the same‐handedness as that of the hexapeptide to form a crystalline st‐PMMA/peptide‐C60 inclusion complex with a unique optically active helix‐in‐helix structure. Although the st‐PMMA is unable to encapsulate the 310‐helical peptide without the terminal C60 unit, the helical hollow space of the st‐PMMA is almost filled by the C60‐bound peptides. This result suggests that the C60 moiety can serve as a versatile molecular carrier of specific molecules and polymers in the helical cavity of the st‐PMMA for the formation of an inclusion complex, thus producing unique supramolecular soft materials that cannot be prepared by other methods. One hand twisting: A one‐handed helical peptide bearing a C60 moiety at one end is encapsulated within the helical cavity of syndiotactic poly(methyl methacrylate) (st‐PMMA) as a result of the C60 moiety which strongly interacts with the st‐PMMA cavity. This encapsulation induces the st‐PMMA backbone to adopt the same handedness as the encapsulated peptides.