Sesquiterpenoids and γ-pyranone derivatives from the whole plant of Erigeron breviscapus and their neuroprotective effects

Abstract Four new sesquiterpenes (1–2, 6–7), a new pyranone glycoside (10) along with six known compounds, were isolated from the whole plant of Erigeron breviscapus. Their planar structures were elucidated using extensive spectroscopic analyses. Brevisterpene A (1) and brevisterpene B (2) were proved to be a pair of diastereomer followed by mixtures resolution using chiral HPLC. Their absolute configurations were determined by ECD calculation. The relative configuration of brevisnoside B (7) was elucidated by a combined analysis of NOESY spectrum and computation of 13C NMR chemical shifts, and determination of the absolute configurations of 6 and 7 assisted by optical rotation calculations. Compounds 1 and 2 displayed moderate neuroprotective effects against H2O2-induced damage in SH-SY5Y cells.