title: Nucleobase Recognition by Artificial Receptors Possessing a Ferrocene Skeleton as a Novel Modular Unit for Hydrogen Bonding and Stacking Interactions.
abstract: Novel ferrocene-modified artificial nucleobase receptors were designed and synthesized. The nucleobase receptors possess hydrogen-bonding and pi-stacking interaction sites that act simultaneously for binding to 1-butylthymine utilizing the pivot character of the ferrocene skeleton. Diamidopyridine was chosen for the hydrogen-bonding moiety, and various polynuclear aromatics were used for pi-stacking one. The two components were tethered to the cyclopentadienyl rings via ethynediyl and oxymethylene spacers. The binding affinity of the receptors to 1-butylthymine was found to be dependent on the aromatic structures. Thus, the association constants for perylene-linked receptors were approximately doubled compared to those of aromatic-free ones, an energy difference of approximately 0.5 kcal/mol. Detailed comparisons between the 10 receptors clarified the value of the pivot character of the ferrocene for construction of the intermolecular interaction site.
authors.affiliation: PRESTO, Japan Science and Technology Corporation (JST), Department of Applied Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Inouye
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Hyodo
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakazumi