Inclusion complex formation of α- and β-cyclodextrins with aminobenzoic acids in aqueous solution studied by 1H NMR
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Complex formation of α- and β-cyclodextrins with para- and meta-aminobenzoic acids in water at 298.15 K was studied by 1H NMR. The formation of 1:1 inclusion complexes in all systems under consideration was observed. Stability constants of the complexes and chemical shift difference induced by 100% complex formation were calculated. The obtained results were discussed in terms of influence of the cyclodextrin cavity size and position of the side amino group in the aromatic ring of aminobenzoic acid molecule on the binding mode and the complex stability.
KeywordsAminobenzoic acid Binding mode Cyclodextrin Inclusion complexes NMR Stability constant
This work was supported by the Russian Science Support Foundation. We would like also to thank N.A. Obukhova for her assistance in the experimental part of work.
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