Two new ditetrahydrofuran lignans from .

Two new ditetrahydrofuran lignans, named sieverlignans A and B ( and ), together with six known ones (-), were isolated from the aerial parts of . Their structures were established on the basis of spectroscopic analysis including HRMS, NMR spectra and circular dichroism experiments. All the compounds were evaluated for their anti-neuroinflammatory effects on the lipopolysaccharides (LPS)-induced nitric oxide production in BV-2 murine microglial cells. Compound exhibited the significant activity with its IC value of 11.9 ± 0.8 μM, respectively, compared to a positive control quercetin with its IC value of 16.0 ± 1.1 μM.