Bioactive Triterpenoids from the Twigs of <i>Chaenomeles sinensis</i>

<i>Chaenomeles sinensis</i> has been consumed traditionally for the treatment of throat diseases, diarrhea, inflammatory diseases, and dry beriberi. Repeated chromatography of the CHCl₃-soluble fraction from the 80% MeOH extract of <i>C. sinensis</i> twigs led to the isolation of three new triterpenoids, sinenic acid A (<b>1</b>), 3β-<i>O</i>-<i>cis</i>-feruloyl-2α,19α-dihydroxyurs-12-en-28-oic acid (<b>2</b>), and 3β-<i>O</i>-<i>cis</i>-caffeoylbetulin (<b>3</b>), together with 20 analogues. The chemical structures of <b>1</b>–<b>3</b> were determined using diverse NMR techniques and HRMS data analysis, chemical methods, and computational approaches supported by advanced statistics (CP3). All the purified compounds were evaluated not only for their cytotoxicity against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-15) but for their potential neuroprotective effects through induction of nerve growth factor in C6 glioma cells. Their anti-inflammatory effects were also assessed by measuring nitric oxide levels in lipopolysaccharide-insulted murine microglia BV2 cells