Four new compunds, belonging to the tetranortriterpenoid family, named dysoxylins A-D (
1-
4), isolated from
Dysoxylumgaudichaudianum, were found to exhibit potent antiviral activity against respiratory syncytial virus (RSV). These structureswere determined by NMR spectroscopy and mass spectrometry and were shown to have anti-RSV EC
50 activities in therange 1.0-4.0
![](/images/entities/mgr.gif)
g/mL in cytopathic effect inhibition and plaque reduction assays.