Four new sesquiterpenes from Curcuma wenyujin

Four new sesquiterpenes including two guaianes (1 and 2), one germacrene (3), and one nor-sesquiterpene (4), which were named as wenyujinols M-P, along with nine known sesquiterpenes (5–13) and three monoterpenes (14–16), were isolated from the rhizomes of Curcuma wenyujin. The chemical structures of 1–4 were elucidated by NMR spectroscopic, mass spectrometric data, and electronic circular dichroism (ECD) spectra analysis. The isolated compounds were evaluated for antioxidant activity via activating the transcription of Nrf2 in 293 T cells. As a result, compounds 6, 13 and 14 exhibited the Nrf2 agonist activity dose-dependently.