NMR spectra and structures of oridonin derivatives complexes with β-cyclodextrin

Magn Reson Chem. 2011 Sep;49(9):611-5. doi: 10.1002/mrc.2770. Epub 2011 Aug 4.

Abstract

Complexations between three oridonin derivatives and β-cyclodextrin (βCD) were studied by nuclear magnetic resonance (NMR) method. Job's plots for complexes were depicted by (1)H NMR spectra chemical shifts, which proved the 1:1 stoichiometry inclusion complex formation between each derivative and βCD. Two-dimensional rotating frame overhauser effect spectroscopy (2D ROESY) support the above conclusion and also proved that ring A of each oridonin derivative deeply enters into hydrophobic cavity from the wider rim and the other parts are outside the cavity. Apparent formation constants (Ka) of complexes between three oridonin derivatives and two CDs are calculated according to Scott's equation.

Keywords: 1H; 3D geometry; NMR; ROESY; host-guest complex; oridonin derivative; β-cyclodextrin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Diterpenes, Kaurane / chemistry*
  • Hydrophobic and Hydrophilic Interactions
  • Kinetics
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Molecular Structure
  • Stereoisomerism
  • beta-Cyclodextrins / chemistry*

Substances

  • Diterpenes, Kaurane
  • beta-Cyclodextrins
  • oridonin
  • betadex