Foldamers as Dynamic Receptors: Probing the Mechanism of Molecular Association between Helical Oligomers and Rodlike Ligands This research was funded by the National Science Foundation (Grant CHE 00-91931). A.T. acknowledges the support of the Japan Society for the Promotion of Science in the form of a Fellowship for Japanese Junior Scientists. The authors gratefully acknowledge Dr. Petr Kuzmic for customizing his program Dynafit to facilitate our data analysis.

Abstract

A dynamic binding mechanism allows the association of dumbbell-shaped ligand 2 with helical folded oligo(m-phenyleneethynylene)s 1 (see schematic representation). Association constants are oligomer length specific, with a maximum value for the icosamer and docosamer. These oligomers have helical conformations that are highly shape-complementary to 1; shorter and longer oligomers exhibit association constants roughly an order of magnitude smaller.