Dataset Information

Glycoluril-Derived Molecular Clips are Potent and Selective Receptors for Cationic Dyes in Water.

ABSTRACT: Molecular clip 1 remains monomeric in water and engages in host-guest recognition processes with suitable guests. We report the K_a values for 32 1⋅guest complexes measured by ¹ H NMR, UV/Vis, and fluorescence titrations. The cavity of 1 is shaped by aromatic surfaces of negative electrostatic potential and therefore displays high affinity and selectivity for planar and cationic aromatic guests that distinguishes it from CB[n] receptors that prefer aliphatic over aromatic guests. Electrostatic effects play a dominant role in the recognition process whereby ion-dipole interactions may occur between ammonium ions and the C=O groups of 1, between the SO₃^- groups of 1 and pendant cationic groups on the guest, and within the cavity of 1 by cation-π interactions. Host 1 displays a high affinity toward dicationic guests with large planar aromatic surfaces (e.g. naphthalene diimide NDI+ and perylene diimide PDI+) and cationic dyes derived from acridine (e.g. methylene blue and azure A). The critical importance of cation-π interactions was ascertained by a comparison of analogous neutral and cationic guests (e.g. methylene violet vs. methylene blue; quinoline vs. N-methylquinolinium; acridine vs. N-methylacridinium; neutral red vs. neutral red H⁺ ) the affinities of which differ by up to 380-fold. We demonstrate that the high affinity of 1 toward methylene blue (K_a =3.92×10⁷ m^-1 ; K_d =25 nm) allows for the selective sequestration and destaining of U87 cells stained with methylene blue.

SUBMITTER: She N

PROVIDER: S-EPMC5150286 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Glycoluril-Derived Molecular Clips are Potent and Selective Receptors for Cationic Dyes in Water.

She Nengfang N Moncelet Damien D Gilberg Laura L Lu Xiaoyong X Sindelar Vladimir V Briken Volker V Isaacs Lyle L

Chemistry (Weinheim an der Bergstrasse, Germany) 20160805 43

Molecular clip 1 remains monomeric in water and engages in host-guest recognition processes with suitable guests. We report the K<sub>a</sub> values for 32 1⋅guest complexes measured by <sup>1</sup> H NMR, UV/Vis, and fluorescence titrations. The cavity of 1 is shaped by aromatic surfaces of negative electrostatic potential and therefore displays high affinity and selectivity for planar and cationic aromatic guests that distinguishes it from CB[n] receptors that prefer aliphatic over aromatic gu ...[more]

PMID: 27492252

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Dataset Information

Glycoluril-Derived Molecular Clips are Potent and Selective Receptors for Cationic Dyes in Water.

Publications

Glycoluril-Derived Molecular Clips are Potent and Selective Receptors for Cationic Dyes in Water.

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