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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 fiveP5S_nhosts 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 betweenP5S_nand 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. 

Abstract We report that the direct macrocyclization of naphthalene monomers bearing ethyl ester functional groups delivers prism[5]arene derivatives, which can be deprotected to yield water‐soluble prism[5]arenes (H1andH3).¹H NMR spectroscopy showed that dicationic guests bind with the hydrophobic cores buried inside the anisotropic magnetically shielding cavity. Isothermal titration calorimetry measurements showed thatH1andH3are high‐affinity hosts in PBS‐buffered water with K_avalues exceeding 10⁹ M⁻¹for a select guest. The complexation events are driven by the non‐classical hydrophobic effect, CH⋅⋅⋅π interactions, and electrostatic interactions. HostH1displays somewhat higher affinity toward a common guest than pillar[6]arene bearing carboxylic acid functional groups but is significantly less potent than pillar[6]arene bearing sulfate groups.H1andH3should be considered alongside other high affinity hosts for a variety of chemical and biological applications. 

The molecular recognition properties of two pillar[n]arene sulfates (P[5]AS and P[6]AS) toward a panel of world anti-doping agency banned substances (1 – 11) were investigated by a combination of isothermal titration calorimetry, 1H NMR spectroscopy, and molecular modelling. Subsequently a sensing ensemble based on indicator displacement was created using the P[5]AS•lucigenin and P[6]AS •Hoechst 33258 complexes which allowed differentiation among the analytes with 90% accuracy. The assay was extended to allow the quantitation of pseudoephedrine in simulated urine samples with a limit of quantitation that is 30-fold below the WADA threshold. 

We report the molecular recognition properties of Pillar[ n ]MaxQ (P[ n ]MQ) toward a series of (methylated) amino acids, amino acid amides, and post-translationally modified peptides by a combination of 1 H NMR, isothermal titration calorimetry, indicator displacement assays, and molecular dynamics simulations. We find that P6MQ is a potent receptor for N -methylated amino acid side chains. P6MQ recognized the H3K4Me 3 peptide with K d = 16 nM in phosphate buffered saline. 

We report an investigation of the complexation between a water soluble pillararene host (WP6) and a panel of hydrophobic cationic guests (G1–G20) by a combination of 1 H NMR spectroscopy and isothermal titration calorimetry in phosphate buffered saline. We find that WP6 forms 1 : 1 complexes with K a values in the 10 4 –10 9 M −1 range driven by favorable enthalpic contributions. This thermodynamic dataset serves as blinded data for the SAMPL9 challenge.