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Journal of Computer-Aided Molecular Design

, Volume 28, Issue 4, pp 319–325 | Cite as

Binding of cyclic carboxylates to octa-acid deep-cavity cavitand

  • Corinne L. D. Gibb
  • Bruce C. Gibb
Article

Abstract

As part of the fourth statistical assessment of modeling of proteins and ligands (sampl.eyesopen.com) prediction challenge, the strength of association of nine guests (19) binding to octa-acid host was determined by a combination of 1H NMR and isothermal titration calorimetry. Association constants in sodium tetraborate buffered (pH 9.2) aqueous solution ranged from 5.39 × 102 M−1 in the case of benzoate 1, up to 3.82 × 105 M−1 for trans-4-methylcyclohexanoate 7. Overall, the free energy difference between the free energies of complexation of these weakest and strongest binding guests was ΔΔG° = 3.88 kcal mol−1. Based on a multitude of previous studies, the anticipated order of strength of binding was close to that which was actually obtained. However, the binding of guest 3 (4-ethylbenzoate) was considerably stronger than initially estimated.

Keywords

Supramolecular chemistry Host-guest chemistry Water Hydrophobic effect 

Notes

Acknowledgments

The authors acknowledge the financial support of the National Institutes of Health (GM098141) in carrying out this research.

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Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  1. 1.Department of ChemistryTulane UniversityNew OrleansUSA

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