Two new coumarins, 6-hydroxymethyl-3-prenyl-7-methoxycoumarin (1) and 6-hydroxyethyl-3-prenyl-7- methoxycoumarin (2), together with three known coumarins (3–5), were isolated from the roots and stems of Yunyan-300, a variety of Nicotiana tabacum L. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were tested for their anti-methicillinresistant Staphylococcus aureus (anti-MRSA) activity and their antioxidant activity. The results revealed that compounds 1 and 2 showed good anti-MRSA inhibitions with IZD of 12.2 ± 1.8 and 11.8 ± 1.5 mm, respectively, and antioxidant activity with an IC50 value of 4.65 and 4.85 μg/mL, respectively.

中文翻译：

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烟草根茎中的两种新香豆素及其生物活性

从根中分离出两种新的香豆素，6-羟甲基-3-异戊二烯-7-甲氧基香豆素 (1) 和 6-羟乙基-3-异戊二烯-7-甲氧基香豆素 (2)，以及三种已知的香豆素 (3-5)和 Yunyan-300 的茎，各种 Nicotiana tabacum L。它们的结构通过光谱方法阐明，包括广泛的 1D 和 2D 核磁共振技术。测试了化合物 1 和 2 的抗甲氧西林金黄色葡萄球菌（抗 MRSA）活性和抗氧化活性。结果表明，化合物1和2显示出良好的抗MRSA抑制作用，IZD分别为12.2±1.8和11.8±1.5 mm，抗氧化活性分别为4.65和4.85 μg/mL的IC50值。