Three new lignanosides from the aerial parts of Lespedeza cuneata

Abstract

Three new lignanosides (+)-(8S,7′S,8′S)-burselignan-9′-O-β-d-glucopyrano side (1), (+)-(8R,7′S,8′R)-isolariciresinol-9′-O-β-d-fucopyranoside (2), (-)-(8S, 7′R,8′R)-methoxyisoariciresinol-9′-O-α-l-rhamnoside (3), along with four known compounds, were isolated from the aerial parts of Lespedeza cuneata (Dum.Cours.) G.Don. The fucopyranoside has not been reported in this genus previously. Their structures and absolute configurations were elucidated on the basis of comprehensive spectroscopic analyses (UV, IR, HR-ESI-MS, 1D and 2D NMR, CD), as well as by comparison with known analogues in the literature. Compounds 2 and 6 showed moderate hepatoprotective activities.

Keywords:

• Lespedeza cuneata
• lignanoside
• hepatoprotective activities