Cyclohexanoid protoflavanones from the stem-bark and roots of Ongokea gore.
Phytochemical investigation of root and stem-bark of the West African medicinal plant Ongokea gore resulted in the isolation of four novel flavonoids with an unusual cyclohexyl substituent instead of the common aromatic ring B. The structures of the isolated compounds were elucidated by spectroscopic methods, mainly 1D and 2D NMR, and subsequently, the structures were corroborated by chemical conversion to (-)-(S)-sakuranetin. The absolute configurations, and preferred conformations were determined by NOE experiments and CD measurements.
Jerz
Gerold
G
Institute of Food Chemistry, Technical University of Braunschweig, Schleinitz-Strasse 20, D-38106 Braunschweig, Germany. g.jerz@tu-bs.de
Waibel
Reiner
R
Achenbach
Hans
H
D000818:Animals; D001156:Artemia; D003510:Cyclohexanes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D044950:Flavanones / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D016488:Medicine, African Traditional; D008956:Models, Chemical; D015394:Molecular Structure; D031656:Olacaceae / Q000737:chemistry*; D024301:Plant Bark / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry*; D018547:Plant Stems / Q000737:chemistry*; D010946:Plants, Medicinal
D003510:Cyclohexanes; D044950:Flavanones