Self-assembling macrocyclic systems
Synthetic peptides, owing to their diversity in size, conformations and appended functionalities, represent highly versatile elements for the construction of bio-inspired H-bonded tubular nanostructures. Likewise, we have shown that macrocyclic oligoureas display a strong propensity to form various types of H-bonded columnar and tubular stacks. Self-assembling properties of hybrid urea/amide macrocycles generated by cyclooligomerization of chiral dipeptide-derived building blocks have been investigated recently.
Figure : Formation of columnar stacks by axial packing of H-bonded dimers of hybrid urea / amide macrocycles and close-ups of the interfaces between duplexes.
A high level of hierarchical and directional control can been achieved in these systems. Recent studies in collaboration with S. matile (Univ Geneva, Switzerland) have shown that these macrocyclic urea/amide hybrids are functional, anion-selective membrane transporters in lipid bilayer membranes.
Selected Publications : Hennig et al. J. Am. Chem. Soc. 2009, 131, 16889-16895. Mocquet et al. J. Am. Chem. Soc. 2009, 131, 14521-14525; Fischer et al. Angew. Chem. Int . Ed. 2009, 48, 1625-1628; Semetey et al. Angew. Chem. Int. Ed. 2002, 41, 1895-1898.