Sesquiterpenoids from <i>Chrysanthemum indicum</i> with Inhibitory Effects on NO Production

Abstract

Three new guaianolide lactones (<b>1</b><b>-3</b>) and four new 9-oxonerolidol glucosides (<b>5</b>-<b>8</b>) together with 20 known compounds were isolated from the MeOH extract of the flowers of <i>Chrysanthemum indicum</i>. Their structures were elucidated based on the interpretation of NMR, HRESIMS, and electronic circular dichroism (ECD) data along with acid hydrolysis. Of the isolates, sesquiterpenoids <b>1</b>-<b>4</b> and <b>15</b> and flavones <b>17</b> and <b>18</b> exhibited inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide production in RAW 264.7 cells with IC₅₀ values in the range 0.2-27.0 μM.