Multitopic supramolecular guests with finely tuned affinities toward widely explored cucurbit[n]urils (CBs) and cyclodextrins (CDs) have been recently designed and tested as functional components of advanced supramolecular systems. We employed various spacers between the adamantane cage and a cationic moiety as a tool for tuning the binding strength toward CB7 to prepare a set of model guests with KCB7 and Kβ-CD values of (0.6-5.0) × 1010 M-1 and (0.6-2.6) × 106 M-1, respectively. These accessible adamantylphenyl-based binding motifs open a way toward supramolecular components with an outstanding affinity toward β-cyclodextrin. 1H NMR experiments performed in 30% CaCl2/D2O at 273 K along with molecular dynamics simulations allowed us to identify two arrangements of the guest@β-CD complexes. The approach, joining experimental and theoretical methods, provided a better understanding of the structure of cyclodextrin complexes and related molecular recognition, which is highly important for the rational design of drug delivery systems, molecular sensors and switches.

CEITEC Central European Institute of Technology Masaryk University Kamenice 5 625 00 Brno Czech Republic

Department of Chemistry Faculty of Science Masaryk University Kamenice 5 625 00 Brno Czech Republic

Department of Chemistry Faculty of Technology Tomas Bata University in Zlín Vavrečkova 275 760 01 Zlín Czech Republic

National Centre for Biomolecular Research Faculty of Science Masaryk University Kamenice 5 625 00 Brno Czech Republic

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Allosteric release of cucurbit[6]uril from a rotaxane using a molecular signal

Two Squares in a Barrel: An Axially Disubstituted Conformationally Rigid Aliphatic Binding Motif for Cucurbit[6]uril

Adamantane-Substituted Purine Nucleosides: Synthesis, Host-Guest Complexes with β-Cyclodextrin and Biological Activity