Application of Mixture Analysis to Crude Materials from Natural Resources (III)~([1]): NMR Spectral Studies to Analyze Chalcones from Angelica keiskei

摘要

This study presents the application of the NMR-based analyses, DOSY and ROSY, to the chalcones, xanthoangelol (1) and 4-hydroxyderricin (2) from Angelica keiskei. We investigated whether virtual separation and structural information from each compound can be obtained. DOSY displays spectra of (1) and (2) in one dimension and diffusion spectra in the other. And the ~1H slice spectra were analyzed in detail by comparison with authentic samples previously isolated from the same material. The resulting ROSY spectrum clearly showed two distinct peaks in the ~1H T_1, dimension. Each slice of the ROSY spectrum along the ~(13)C dimension contains over-lapped signals, which are difficult to assign at this time. The result of our experiments shows that DOSY and ROSY are very useful as methods for various kinds of mixture analyses to crude natural materials.