Eupomatenes A – E: Neolignans isolated from the leaves of Australian rainforest plant Eupomatia laurina

Abstract

A detailed phytochemical investigation of the leaves of the Australian rainforest tree Eupomatia laurina, led to the discovery of five new neolignans, eupomatenes A – E and eight known compounds, eupomatenoid-2, trans-(2′S)-2-[1′-(4-methoxyphenyl)prop-2′-yl]anethol, chlorogenic acid, chlorogenic acid-methyl ester, tyrosol-1-O-β-xylopyranosyl-1(1 → 6)-O-β-glucopyranoside, leucoside, kaempferol-3-O-neohesperidoside, and pachypodol. The structures of all the compounds were determined by detailed spectroscopic analysis. All compounds were also evaluated for their anti-inflammatory properties by assessing their inhibitory effects on nitric oxide (NO) production and TNF- α release in RAW 264.7 macrophages. Whilst slight anti-inflammatory activity (in terms of inhibition of NO production) was observed with eupomatenes A – E, this was also associated with high levels of cell growth inhibition.