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Abstract We report the synthesis and characterization of sulfated pillar[5]arene hosts (P5S2‐P5S10) that differ in the number of sulfate substituents. All fiveP5Snhosts display high solubility in water (73–131 mM) and do not undergo significant self‐association according to1H NMR dilution experiments. The x‐ray crystal structures ofP5S6,P5S6 ⋅ Me6HDA,P5S8 ⋅ Me6HDA, andP5S10 ⋅ Me6HDAreveal one intracavity molecule ofMe6HDAand several external molecules ofMe6HDAwhich form a network of close methonium ⋅ ⋅ ⋅ sulfate interactions. The thermodynamic parameters of complexation betweenP5Snand the panel of guests was measured by direct or competitive isothermal titration calorimetry. We find that the binding free energy toward a guest becomes more negative as the number of sulfate substituents increase. Conversely, the binding free energy of a specific sulfated pillar[5]arene toward a homologous series of guests becomes more negative as the number of NMe groups increases. The ability to tune the host ⋅ guest affinity by changing the number of sulfate substituents will be valuable in supramolecular polymers, separation materials, and latching applications.
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Pillar[ n ]MaxQ: A New High Affinity Host Family for Sequestration in Water
Abstract We report the synthesis, X‐ray crystal structure, and molecular recognition properties of pillar[n]arene derivativeP[6]AS, which we refer to as Pillar[6]MaxQ along with analoguesP[5]ASandP[7]AStoward guests1–18. The ultratight binding affinity ofP[5]ASandP[6]AStoward quaternary (di)ammonium ions renders them prime candidates for in vitro and in vivo non‐covalent bioconjugation, for imaging and delivery applications, and as in vivo sequestration agents.
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- Award ID(s):
- 1404911
- PAR ID:
- 10161858
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 59
- Issue:
- 32
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 13313-13319
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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