Extraction of radio-labelled xanthine derivatives by artificial receptors: deep insight into the association behaviour

Chemistry. 2007;13(13):3724-32. doi: 10.1002/chem.200601231.

Abstract

Association constants for the interaction of almost insoluble substrates with triphenylene ketal-based receptors in toluene have been determined by means of an extraction method employing the corresponding radio-labelled substrates. Flexible and more polar receptors tend to aggregate and exhibit inferior extraction qualities. Binding constants in toluene were found to be in the range 10(5)-10(7) m(-1), which is significantly higher than in dichloromethane. X-ray analyses indicate the direct participation of a water molecule in the binding process, which may account for the surprisingly small effect of moisture in the solvent on the stability of the complexes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Binding Sites
  • Binding, Competitive
  • Caffeine / chemistry
  • Crystallography, X-Ray
  • Methylene Chloride / chemistry
  • Models, Molecular
  • Molecular Structure
  • Radioisotopes / chemistry
  • Receptors, Peptide / chemistry*
  • Receptors, Peptide / drug effects
  • Solvents
  • Theophylline / chemistry
  • Toluene / chemistry
  • Xanthines / chemistry*

Substances

  • Radioisotopes
  • Receptors, Peptide
  • Solvents
  • Xanthines
  • Toluene
  • Caffeine
  • Methylene Chloride
  • Theophylline