Chlorinated illudalane sequiterpenoids from Saxiglossum angustissimum

Eight chlorinated illudalane sesquiterpenoids were isolated from the aerial parts of Saxiglossum angustissimum, including a pair of new pterosin enantiomers, (2R)-angupterosin (1) and (2S)-angupterosin (2), as well as a new pteroside, angupteroside (3). The structures of these compounds were determined through comprehensive analysis of HRESI-MS, NMR spectral data, ECD, and comparisons with previously reported literature. Remarkably, these chlorine-containing compounds (1-8) are rare and represent the first discovery of such metabolites within the family Pyrrosioideae. The chlorinated illudalane sesquiterpenoids from S. angustissimum may serve as valuable chemotaxonomic markers for this species. Furthermore, compounds 1-8 demonstrated inhibitory effects on LPS-induced NO release in BV2 cells, highlighting their potential anti-inflammatory properties.