NMR as a tool for simultaneous study of diasteroisomeric inclusion complexes, part 2: Complexes formed by racemic mixture of 4′- hydroxyflavanone and two cyclodextrins

Complexes formed by (±)-4′-hydroxyflavanone (OHFL) and the cyclodextrins β-cyclodextrin and (2-hydroxypropyl)-β-CD were obtained using the racemic mixture of the OHFL. These complexes were able to be studied due to their enantiodifferentiation by 1H-NMR spectroscopy. Stoichiometry, association constants and thermodynamic parameters were obtained from these NMR data, and inclusion geometries were proposed from ROESY spectra. The results show a 1:1 stoichiometry, K a values decrease with increasing temperature, a spontaneous and exothermic complexes formation, and that ROESY spectra cannot differentiate between enantiomers, and therefore the estimated inclusion geometries were proposed for the mixture of diasteroisomeric complexes. © 2011 Springer Science+Business Media B.V

NMR as a tool for simultaneous study of diastereoisomeric inclusion complexes formed by racemic mixture of 4′-hydroxyflavanone and heptakis-(2,6-O-dimethyl)-β-cyclodextrin

The complexes formed by (±)-4′-hydroxyflavanone (OHFL) and heptakis-(2,6-O-dimethyl)-β-cyclodextrin (DM-β-CD) were obtained using the racemic mixture of OHFL. These complexes were able to be studied due to their enantiodifferentiation by 1H-NMR spectroscopy. Stoichiometry, association constants and thermodynamic parameters were obtained from these NMR data, and inclusion geometries were proposed from ROESY and docking experiments. The results show that diastereoisomeric complexes can be studied even when they are formed by enantiomeric mixtures. © 2010 Springer Science+Business Media B.V