Megastigmane glycoside and phenol glycosides from the bark of Mallotus barbatus

Abstract

A new megastigmane glycoside, barbatcoside A (1), and two new phenol glycosides, barbatcosides B (2) and C (3), together with eight known compounds (4-11) were isolated from the bark of Mallotus barbatus Müll. Arg. Their structures were elucidated using extensive 1D and 2D NMR as well as HRESIMS spectroscopic data. The stereochemistry of compounds 1 and 2 were established based on the experimental CD curves. The anti-inflammatory activities of compounds 1-11 from M. barbatus were evaluated using LPS-stimulated RAW 264.7 cell models. Compounds 2 and 3 substantially inhibited the release of NO with IC50 values of 34.78 μM and 20.73 μM, respectively.