Determination of the absolute configuration of natural products in solution using an integrated experimental and theoretical approach

点击翻译按钮获取中文摘要

The determination of the absolute configuration of natural products is still a formidable task. In this proposal an integrated approach is formulated: experimental spectroscopic data (NMR, ECD, UV-Vis, IR, VCD, optical rotation data: all easily available from literature) are doubled by DFT calculated data. A statistical evaluation will be conducted with the series of the well-known menthol diastereomers (menthol, isomenthol, neomenthol, neoisomenthol). In this way an integrated approach is established which will then be applied to partly unknown cases of current research: the flavones of Silybum marianum (L.) and the family of eupomatilones. The analysis of series of compounds allows the establishment of limits of confidence for the determination of the absolute configuration. Based on this approach not only already isolated and synthesized isomers can be differentiated, but also natural products for which samples are no longer available.