Ion-Pair Recognition by Nucleoside Self-Assembly: Guanosine Hexadecamers Bind Cations and Anions
Xiaodong Shi1, James C Fettinger1, Jeffery T Davis1
1Department of Chemistry and Biochemistry University of Maryland College Park, MD 20742 (USA) Fax: (+1) 301-314-9121.
Abstract:
G-Quartets can bind anions as well as cations: Solid-state and solution data indicate that self-assembled ion-pair receptors are formed from 16 guanosine monomers, 2 divalent cations, and 4 picrate anions. Hydrogen-bonding, ion-dipole, and base-stacking interactions combine to give a tubular complex with a cation-loaded interior. An array of hydrogen-bond donors on the receptor's surface then enables anion coordination (see schematic representation, shaded rectangles=G-quartets, shaded circles=cations).
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