Two New Chromone Derivatives from Cassia leschenaultiana and Their Anti-Tobacco Mosaic Virus Activity

Two new compounds ( 1 and 2 ), together with three known chromone derivatives ( 3 – 5 ), were isolated from Cassia leschenaultiana . Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were evaluated for their anti-tobacco mosaic virus (anti-TMV) activity. The results showed that compounds 1 and 2 showed potential anti-TMV activities with inhibition rates of 35.6% and 38.7% at the concentration of 20 μM, respectively. These rates are higher than that of the positive control.