Labdane diterpenoids from Lagopsis supina and their anti-neuroinflammatory activity.

In this study, ten labdane-type diterpenoids 1-10 were isolated from a methanol extract of the whole plant Lagopsis supina, including three undescribed compounds 1-3. Their structures were determined by spectroscopic data analyses such as HR-ESI-MS, 1D, and 2D NMR, as well as comparison with literature data. At the same time, the absolute configuration of five compounds 2-5 and 10 was confirmed for the first time by the single crystal X-ray diffraction method. All the compounds were isolated from L. supina for the first time. The CCK-8 assay showed that all compounds had no significant damage to BV-2 microglial cells, and then screened their inhibitory effects of nitric oxide production stimulated by lipopolysaccharide in BV-2 microglial cells. The pharmacological results showed that compound 4 greatly inhibited LPS-stimulated NO release at the concentration of 10 μM, indicating that it has potential anti-neuroinflammatory activity.