Foldamer-based molecular recognition

The ordered solution conformation of a synthetic chain molecule has been used to create a high-affinity binding site for small-molecule guests. The diastereoselective complexation of chiral monoterpenes with an achiral, amphiphilic In-phenylene ethynylene oligomer is demonstrated by induced circular dichroism in polar solvents. The stoichiometry of this solvophobically driven, reversible complex is strictly 1:1. The results are interpreted as a preferential binding of the chiral guest to one of the oligomer's enantiomeric helical conformations. Evidence for binding within the hydrophobic tubular cavity of the helix is provided by studies on modified oligomers.