title: NMR spectra and structures of oridonin derivatives complexes with β-cyclodextrin.
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.
authors.affiliation: New Drug Research and Development Center, School of Pharmaceutical Science, Zhengzhou University, Zhengzhou 450001, P. R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Bing
authors.initials: B
authors.lastname: Zhao
authors.forename: Yin-Chao
authors.initials: YC
authors.lastname: Li
authors.forename: Hong-Min
authors.initials: HM
authors.lastname: Liu
mesh_terms: D045786:Diterpenes, Kaurane / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D013237:Stereoisomerism; D047392:beta-Cyclodextrins / Q000737:chemistry*
chemical_list: D045786:Diterpenes, Kaurane; D047392:beta-Cyclodextrins; C011959:oridonin; C031215:betadex