Arvestolides A–C, new rare sesquiterpenes from the aerial parts of Artemisia vestita

Three new sesquiterpenes, namely arvestolides A–C (1–3), were isolated from the aerial parts of Artemisia vestita. Their planar structures were determined by extensive analysis of spectroscopic data including MS, 1D, and 2D NMR, and their absolute configurations were resolved by single-crystal X-ray diffraction. Compound 1 is a sesquiterpene with a rare 6/8/3 skeleton, while compounds 2 and 3 possess a rare 5/8/3 sesquiterpene skeleton. Compound 2 exhibited a moderate inhibition effect on the lipopolysaccharide (LPS)-induced nitric oxide (NO) production in BV-2 microglial cells with an IC50 value of 38.59 μM.