There were five sesquiterpene lactones, belonging to the eudesmanolide class, isolated from the halophyte Sonchus brachyotus DC. The structures of the compounds were determined using spectroscopic methods, including 1D and 2D NMR spectra, MS data, and optical rotation values. Compounds 4 and 5 were characterized by the position of p-hydroxyphenylacetyl group in the sugar moiety. In the evaluation of anti-inflammatory effects on LPS-activated RAW264.7 macrophages, compound 1, 5α,6βH-eudesma-3,11(13)-dien-12,6α-olide, potently suppressed the expression of iNOS and COS-2, as well as the production of TNF-α, IL-6, and IL-10. Treatment of 1 regulates the Nrf2/HO-1 pathway.
Keywords: Sonchus brachyotus; anti-inflammation; eudesmanolide; sesquiterpene lactone.