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

A one‐handed 3(10)‐helical hexapeptide is efficiently encapsulated within the helical cavity of st‐PMMA when a fullerene (C(60)) 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‐C(60) inclusion complex with a unique optically active helix‐in‐helix structure. Although the st‐PMMA is unable to encapsulate the 3(10)‐helical peptide without the terminal C(60) unit, the helical hollow space of the st‐PMMA is almost filled by the C(60)‐bound peptides. This result suggests that the C(60) 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.