Isolation of a new natural kingiside aglucone derivative and other anti-inflammatory constituents from <i>Syringa reticulata</i>

Abstract

A new secoiridoid, (1<i>R</i>,5<i>S</i>,8<i>S</i>,9<i>R</i>)-1-methyl-kingiside aglucone (<b>1</b>), along with nine known compounds (<b>2</b>-<b>10</b>), were isolated from the ethanol extract of the stem bark of <i>Syringa reticulata</i> (Bl.) Hara. The structure of compound <b>1</b> was elucidated using HR-ESI-MS, 1D and 2D NMR spectroscopy. Compounds <b>1</b>-<b>10</b> were evaluated for their inhibitory activity against NO, TNF-α and IL-6 production. Compounds <b>1</b>, <b>3</b>, <b>5</b> and <b>7</b>-<b>10</b> significantly inhibited the levels of NO, TNF-α and IL-6 in LPS-induced RAW264.7 cells from concentrations of 3 to 30 μM.