Lignan Glycosides from the Twigs of <i>Chaenomeles sinensis</i> and Their Biological Activities

Phytochemical investigation of the twigs of <i>Chaenomeles sinensis</i> led to the isolation and identification of six new lignan glycosides, chaenomiside A–F (<b>1</b>–<b>6</b>), along with five known ones (<b>7</b>–<b>11</b>). Their chemical structures were determined by spectroscopic methods, including NMR, MS, ECD, and GC/MS analyses. All the isolated compounds (<b>1</b>–<b>11</b>) were tested for their inhibitory effects on nitric oxide (NO) production in lipopolysaccharide-activated murine microglial cells and the secretion of nerve growth factor (NGF) in a C6 rat glioma cell line. Compound <b>6</b> significantly reduced NO levels in the murine microglia BV2 cells with an IC₅₀ value of 21.3 μM, and compounds <b>1</b>, <b>3</b>, and <b>6</b> were potent stimulants of NGF release with stimulation levels of 151.74 ± 6.77%, 144.31 ± 7.49%, and 167.61 ± 18.5%, respectively