文摘
The absolute configuration of knipholone, an axially chiral phenylanthraquinone from Kniphofia, Bulbine, and Bulbinella species, has been established as M by quantum chemical CD calculations. For further evidence, the absolute stereostructure of the related compound knipholone anthrone, which has a significantly different chromophor, was likewise elucidated. The fact that both natural biaryls compounds were independently attributed the same absolute configuration, underlines the reliability of the results and the value of the applied method.