Abstract
A new sesquiterpene (1) and a new norsesquiterpene (2) belonging guaiane-type skeleton together with six known compounds (3–8) were isolated from the rhizomes of Alisma plantago-aquatica. Their structures were determined by HR-ESI-MS, 1D and 2D NMR spectroscopic methods. Absolute configurations of new compounds were established by experimental and TD-DFT computational ECD spectra. Compounds 1–8 exhibited xanthine oxidase inhibitory activity with their IC50 values in range of 9.4–66.7 μM. The sesquiterpenoids 1–5 displayed the inhibitory activity and hence they could be potential xanthine oxidase inhibitors from A. plantago-aquatica.