Structures and Biological Activities of Polyacylated -Kaurane Diterpenoid Glycosides from the Aerial Parts of .

Sixteen new (-) and three known (-) polyacylated -kaurane diterpenoid glycosides were isolated from the aerial parts of . The planar structures of - and their relative configurations were established on the basis of extensive spectroscopic analysis. The absolute configurations of all stereogenic centers for compounds and were determined by single-crystal X-ray diffraction experiments, and the absolute configurations of the other new compounds were assigned by chemical degradation and experimental ECD data. Antineuroinflammatory testing of all the isolates showed that compound inhibited lipopolysaccharide-induced nitric oxide production in BV-2 microglial cells with an IC value of 15.6 μM. In an α-glucosidase inhibitory assay, compound exhibited a strong inhibitory effect with an IC value of 32.8 μM, whereas the IC value of the positive control, acarbose, was 387.8 μM.