THREE NEW ISOBENZOFURANS FROM THE STEMS OF ORIENTAL TOBACCO AND THEIR BIOACTIVITIES

摘要

Three new isobenzofurans (1-3), together with four known furan derivatives (4-7) were isolated from the stems of oriental tobacco. Their structures were determined by means of HRESIMS and extensive 1D and 2D NMR spectroscopic studies. Compounds 1-7 were tested for their anti-tobacoo mosaic virus (TMV) activities and cytotoxicity activities. The results revealed that compounds 2 and 3 showed high anti-TMV activities with inhibition rates of 35.4, and 34.2%. These rates are higher than that of positive control. Other compounds also showed anti-TMV activities with inhibition rates in the range of 18.6 similar to 22.7%. These rates are close to that of positive control. Compounds 1-7 also showed moderate-to-weak inhibitory activities against some tested human tumor cell lines with IC50 values in the range of 2.8-9.3 mu M.