Three new ent-kaurene diterpenoid glucosides from the flowers of Inula japonica Thunb

Nat Prod Res. 2025 Jun 16:1-6. doi: 10.1080/14786419.2025.2513587. Online ahead of print.

Abstract

Three new ent-kaurene diterpenoid glucosides-Inunicosides L (1), M (2), and N (3)-along with five known analogs (4-8) were isolated from Inula japonica Thunb. Their structures were characterised using 1D and 2D NMR, HRESIMS, and electronic circular dichroism analysis. All compounds were assessed for anti-inflammatory activity.

Keywords: Inula japonica Thunb.; NO production; anti-inflammatory activity; ent-kaurene diterpenoid glucosides; structural elucidation.