Supramolecular Interactions between β-Cyclodextrin and the Nucleobase Derivatives of Ferrocene

Abstract

Novel conjugates of ferrocene with uracil, 5-fluorouracil, tegafur, or acyclovir are reported. Their synthesis involved (i) the azide–alkyne 1,3-dipolar cycloaddition or (ii) the formation of the ester linkage. For the first time, we present an in-depth insight into the supramolecular interactions between β-cyclodextrin and ferrocene-nucleobase derivatives. Spectroscopic and voltammetric analyses performed within this work suggested that the ferrocene or adamantane unit of the conjugates interacted with the β-cyclodextrin’s inner cavity. The methods applied for the supramolecular studies included 1H–1H ROESY NMR, 1H NMR titration, Fourier-transform infrared spectroscopy, cyclic voltammetry, fluorescence spectra titration, and 1H DOSY NMR. 1H DOSY NMR was also employed to evaluate the apparent binding constants for all the complexes. The ferrocene–acyclovir conjugate Fc-5 featured the highest apparent binding constant value among all the complexes tested.

Synthesis of benzoin under supramolecular catalysis involving cyclodextrins in water: application for the preparation of the antiepileptic drug phenytoin

“…NMR is a powerful tool for studying the conformation of inclusion complexes, 32 especially the 2D rotating frame 1 H– 1 H nuclear Overhauser effect (2D-ROESY) because of its reliable and detailed information on the molecular geometry of those inclusion complexes.…”

“…To reveal the plausible mechanisms of the reactions catalyzed by HP-b-CD in water, the geometries of inclusion complexes were investigated. NMR is a powerful tool for studying the conformation of inclusion complexes, 32 especially the 2D rotating frame 1 H-1 H nuclear Overhauser effect (2D-ROESY) because of its reliable and detailed information on the molecular geometry of those inclusion complexes.…”

Cyclodextrins in the antiviral therapy

“…Although some antiviral molecules, including aciclovir, can be conjugated to ferrocenyl-CD complexes [99], their pharmacological use is expected only in the distant future.…”

Competitive Self-Assembly Interaction between Ferrocenyl Units and Amino Acids for Entry into the Cavity of β-Cyclodextrin for Chiral Electroanalysis

“…Cyclodextrins, derived from glucose via dehydration condensation, have a hydrophobic inner cavity. It is known that a supramolecular assembly can occur between β-cyclodextrin (β-CD) and Fc to form an inclusion complex. − Meanwhile, β-CD, as a typical chiral selector, has shown great identification ability toward different kinds of isomers. ,,− Thus, we speculate that the host–guest recognition between macrocyclic supermolecules and guest molecules can be harnessed as an efficient technique for chiral analysis. − That is, a competitive interaction occurs between the testing isomers and Fc for entry into the cavity of β-CD. Then, it will produce the corresponding signals of Fc regardless of the electroactive units derived from the testing isomers.…”