A new cadinane sesquiterpenoid from Eupatorium adenophorum and α-glycosidase and AChE inhibitory activities of a gossypetin acylglucoside

AbstractTo investigate the chemical constituents ofEupatorium adenophorum Spreng. (syn. Ageratina adenophora (Spreng.) R.M. King& H. Rob.) growing in Vietnam, the water-soluble fraction from the leaf methanol extract was fractionated by column chromatography. A new sesquiterpenoid, named adenophorone (1), was isolated along with 11 known compounds (2-12). The interpretation of HR-MS and 1D and 2D NMR spectroscopic data together with experimental and theoretical ECD calculations established the absolute stereostructure of compound1. Two isolated flavonol glucosides9 and10 were subjected to enzyme inhibition assays. Gossypetin 5-O-(6 ′′-(E)-caffeoyl)-β-D-glucopyranoside (9) inhibitedα-glycosidase activity with an IC50 value of 24.0  ± 1.61 μg/mL (80% inhibition at 256 μg/mL) and acetylcholinesterase activity with an IC50 value of 217.60  ± 15.47 μg/mL (54% inhibition at 256 μg/mL). Quercetagetin 7-O-β-D-glucopyranoside (10) slightly inhibited the two enzymes (27% and 34% inhibition, respectively) at the maximal tested concentration of 256  μg/mL. The present study is the first report on the chemical constituents of the water-soluble fraction ofE. adenophorum. The study also provides some evidence for theα-glycosidase and acetylcholinesterase activities of the rare polyhydroxyflavonol acylglycoside gossypetin 5-O-(6 ′′-(E)-caffeoyl)-β-D-glucopyranoside.
Source: Medicinal Chemistry Research - Category: Chemistry Source Type: research