Structurally Diverse Sesquiterpenoid Glycoside Esters from with Anti-neuroinflammatory Activity.

Thirteen new sesquiterpenoid glycoside esters, including 11 aromadendrane-type compounds, pitqinlingosides A-K (-), one cadinane-type compound, pitqinlingoside L (), and one eudesmane-type compound, pitqinlingoside M (), together with seven known analogues (-) were isolated from the twigs, fruits, and leaves of Structures were elucidated by analysis of spectroscopic data, gas chromatography mass spectrometry (GC-MS), and chemical methods. The absolute configuration was confirmed by single-crystal X-ray crystallography analysis or electronic circular dichroism spectra. Unusual glycoside esters are characterized by the presence of polyacylated β-d-fucopyranosyl, β-d-glucopyranosyl, and β-d-xylopyranosyl units. Pitqinlingosides A (), B (), D (), and F (), pittosporanoside A acetate (), and pittosporanoside A () showed significant nitric oxide production inhibition in lipopolysaccharide (LPS)-induced BV-2 microglial cells with IC values ranging from 0.95 to 24.12 μM. Structure-activity relationships of the isolated compounds are discussed.