Abstract
The 13C-NMR spectra of 61 flavone derivatives were measured in dimethyl sulfoxide. By consideration of the chemical shifts of skeletal carbons, the parameters (α and β values) and correction factor (ο value) necessary for calculating their carbon shifts were deduced. The skeletal carbons of polysubstituted flavones and flavonols could easily be assigned by the use of these values and SCS of OMe or OH. The 13C-NMR spectra were confirmed to give useful information that could not be obtained from other spectral data. The data were applied for the structure elucidation of unknown polysubstituted flavones.
