Two new flavones, namely 5-hydroxy-2-(4′-hydroxyphenyl)-6,12,13-trimethoxypyrano-xanthene-4,9-dione (1) and 5-hydroxy-2-(3′-methoxy-4′-hydroxyphenyl)-6-methoxy-11-isopropyl-pyranochromene-4,9-dione (2), were isolated from Salvia plebeia. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR spectral data. Compounds 1 and 2 were evaluated for their anti-angiogenic activities by the MTT assay with axitinib as positive control, and they displayed moderate anti-angiogenic activities with IC50 values of 14.07 and 11.25 μM, respectively.

中文翻译：

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鼠尾草的两种新黄酮及其抗血管生成活性

两种新的黄酮，即5-羟基-2-(4'-羟基苯基)-6,12,13-三甲氧基吡喃-氧杂蒽-4,9-二酮(1)和5-羟基-2-(3'-甲氧基-4) '-羟基苯基)-6-甲氧基-11-异丙基-吡喃酮-4,9-二酮(2)，从鼠尾草中分离。它们的结构通过光谱方法阐明，包括广泛的 1D 和 2D NMR 光谱数据。使用阿西替尼作为阳性对照，通过 MTT 测定评估化合物 1 和 2 的抗血管生成活性，它们显示出中等的抗血管生成活性，IC50 值分别为 14.07 和 11.25 μM。