THREE NEW ISOINDOLIN-1-ONES FROM THE LEAVES OF YUNNAN LOCAL SUN CURED TOBACCO AND THEIR BIOACTIVITIES

Three new (1-3) and one known (4) isoindolin-1-ones were isolated from the leaves of Yunnan local sun cured tobacco. Their structures were determined by means of HRESIMS and extensive 1D and 2D NMR spectroscopic studies. Compounds 1-3 were tested for their anti-tobacco mosaic virus (anti-TMV) activities and compounds 1-4 were tested for their cytotoxicity activities. The results showed that compounds 1-3 showed high anti-TMV activity with inhibition rates of 43.8, 45.6 and 52.7%. These rates are higher than that of positive control. Compounds 1-4 also showed moderate-to-weak inhibitory activities against some tested human tumor cell lines with IC50 values in the range of 2.8-8.2 mu M.