Three new isobenzofurans from Lavandula angustifolia and their bioactivities

Three new isobenzofurans, lavandulactones A-C (1-3), together with three known ones (4-6), were isolated from the whole herb of Lavandula angustifolia. Their structures were established on the basis of detailed spectroscopic analysis (1D-and 2D-NMR, HRESIMS, UV, and IR) and comparison with data reported in the literature. New isolates were evaluated for their anti-tobacco mosaic virus (TMV) activities and cytotoxicity activities. The results revealed that compounds 1-3 showed high anti-TMV activity with inhibition rate of 31.8, 29.6 and 33.4%, respectively. These rates are higher than that of positive control. Compounds 1-3 also showed weak inhibitory activities against some tested human tumor cell lines with IC50 values ranging from 1.5 to 5.7 mu M. (C) 2016 Published by Elsevier Ltd on behalf of Phytochemical Society of Europe.