| Popis: |
A phytochemical study of the ethanolic extract of the leaves of Ligularia virgaurea led to the isolation of a new eremophilane-type sesquiterpene lactone, (4S,5R,6S,8S,lR)-6β-angeloyloxy-eremophil-7(l l)-en-10βH-8α,12-olide (1), along with a known eremophilane-type sesquiterpene, (4S,5R,6S,lOS)-6β- angeloyloxy-10βH-furanoeremophil-9-one (2). Their structures were elucidated by extensive spectroscopic methods, including ID and 2D nuclear magnetic resonance and high-resolution electrospray ionization mass spectrometry experiments, and the absolute configurations were confirmed by single-crystal X-ray diffraction analysis using the anomalous scattering of Cu Ka radiation. |
