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Updated: Dec 25, 2025

Caffeine Extraction, Enzymatic Activity and Gene Expression of Caffeine Synthase from Plant Cell Suspensions
Published on: October 2, 2018
Effective Recognition of Caffeine by Diaminocarbazolic Receptors
Oscar Francesconi1, Andrea Ienco2, Cristina Nativi1
1Department of Chemistry "Ugo Schiff" and INSTM, University of Florence, Polo Scientifico e Tecnologico, I-50019 Sesto Fiorentino, Firenze, Italy.
Abstract:
Caffeine is a competitive inhibitor of adenosine receptors and possesses wide pharmacological activity. Artificial receptors recognizing caffeine potentially have a wide range of biomedical and industrial applications. Herein, we describe two structurally related and readily available artificial receptors: 1) a macrocyclic receptor, which binds caffeine with the unprecedented affinity of 9.3 μM, though with poor selectivity; and 2) a tweezers-like structure, showing an affinity of 26 μM and a 4.5-fold and 6-fold selectivity compared to theophylline and theobromine, respectively. Binding affinities were measured by 1 H NMR titrations and were confirmed by isothermal titration calorimetry. The X-ray structure of the complex between caffeine and the acyclic receptor revealed the origin of the recognition, explained the selectivity, and shed light on the role of hydrogen bonding and CH-π/π-π interactions.
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