New Eudesmane-Type Sesquiterpene Glycosides from the Leaves of Aster koraiensis

Abstract

Four new eudesmane-type sesquiterpenoids, (1R,5S,6R,7S,9S,10S)-1,6,9-trihydroxy-eudesm-3-ene-1,6-di-O-β-d-glucopyranoside (1), (1R,5S,6S,7R,9S,10S)-1,6,9,11-tetrahydroxy-eudesm-3-ene-1,6-di-O-β-d-glucopyranoside (3), (1R,5S,6R,7S,9S,10R)-9-O-(Z-p-coumaroyl)-1,6,9-trihydroxy-eudesm-3-ene-6-O-β-d-glucopyranoside (6), and (1R,5S,6R,7S,9S,10R)-9-O-(E-feruloyl)-1,6,9-trihydroxy-eudesm-3-ene-6-O-β-d-glucopyranoside (7), were isolated from a 95% EtOH extract of the leaves of Aster koraiensis by repeated chromatography. Moreover, three sesquiterpenoids (2, 4, and 5) and two caffeoylquinic acids (8 and 9) having previously known chemical structures were isolated during the isolation procedure. The four new compounds (1, 3, 6, and 7) were elucidated by spectroscopic data (1D- and 2D-NMR, MS, and ECD) interpretation and hydrolysis. Moreover, the absolute configurations of 2, 4, and 5 were determined for the first time in this study. The compounds isolated were tested for their viability on nitric oxide (NO) and prostaglandin E2 (PGE2) production on LPS-stimulated RAW 264.7 cells. Among them, only 7 presented weak inhibitory effects on both NO and PGE2 production.

Neuroprotective Properties of Eudesmin on a Cellular Model of Amyloid-β Peptide Toxicity

“…Eudesmin (Eu) (Fig. 1A) is a tetrahydrofurofuranoid lignan that has been isolated from numerous medicinal plants and shown several biological activities including cytotoxic, antibacterial, antifungal, anti-inflammatory, immunostimulant, and inhibitory effects on tumor necrosis factor-alpha (TNF-␣) production as well as improving the neurite outgrowth [11,39,40,42,43]. Moreover, Eu has been reported mainly from the genus Artemisia, exhibiting nitric oxide (NO) inhibitory effects and cytotoxic activities [39,40].…”