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.

中文翻译：

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决明子的两种新色酮衍生物及其抗烟草花叶病毒活性

从 Cassia leschenaultiana 中分离出两种新化合物（1 和 2）以及三种已知的色酮衍生物（3-5）。它们的结构是通过光谱方法阐明的，包括广泛的 1D 和 2D NMR 技术。评估了化合物 1 和 2 的抗烟草花叶病毒（抗 TMV）活性。结果表明，化合物1和2在20 μM浓度下显示出潜在的抗TMV活性，抑制率分别为35.6%和38.7%。这些比率高于阳性对照的比率。