Three new (1-3), together with three known (4-6) quinoline alkaloids were isolated from the leaves of cigar tobacco (a variety of Nicotiana tabacum). Their structures were elucidated by spectroscopic methods, including extensive 1H, 13C, and 2D-NMR techniques. Compounds 1-6 were tested for their anti-tobacco mosaic virus (anti-TMV) activity. The results showed that compound 3 exhibited high anti-TMV activity with inhibition rate of 42.2% at the concentration of 20 μM. This rate in higher than that of positive control (with inhibition rate of 32.5% at the concentration of 20 μM). Compounds 1, 2, 4~6 also showed potential anti-TMV activity with inhibition rates of 28.2, 31.0, 22.8, 26.6, and 29.5% at the concentration of 20 μM, respectively. These rates are slightly lower than that of positive control.

中文翻译：

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雪茄烟叶中喹啉生物碱及其抗烟草花叶病毒活性

三个新的（1 - 3 ）中，用三个已知（一起4 - 6 ）喹啉生物碱从雪茄烟草的叶中分离（各种烟草）。它们的结构通过光谱方法阐明，包括广泛的1 H、13 C 和 2D-​​NMR 技术。化合物1 - 6为自己的反烟草花叶病毒（抗TMV）的活性进行了测试。结果表明，化合物3在20 μm浓度下表现出较高的抗TMV活性，抑制率为42.2%。 M.该速率在比阳性对照（在20的浓度的32.5％抑制率的更高μ M）。化合物1 ，2 ，4 〜6也显示出潜在的抗TMV活性与抑制率28.2，31.0，22.8，26.6，和在20的浓度29.5％μ男，分别。这些比率略低于阳性对照的比率。