Two new alkaloids (1–2), and four known ones (3–6) were isolated from branches of Cephalotaxus hainanensis Li. The structures of new alkaloids were elucidated by extensive analysis of HRESIMS, 1D and 2D NMR data. The absolute configuration of compound 2 was established on the basis of experimental and computed ECD data. All compounds were evaluated for their cytotoxic activity against K562, BEL-7402, SGC-7901, A549, and Hela human cancer cell lines. Compound 6 exhibited significant activity with IC₅₀ values ranging from 4.86 to 26.56 μM, respectively.

中文翻译：

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从两个新生物碱海南粗榧李

两个新的生物碱（1 - 2），和四个公知的（3 - 6）购自海南粗榧李的分支隔离。通过对HRESIMS，1D和2D NMR数据的广泛分析，阐明了新生物碱的结构。化合物2的绝对构型是根据实验和计算得出的ECD数据确定的。评估所有化合物对K562，BEL-7402，SGC-7901，A549和Hela人癌细胞系的细胞毒活性。化合物6表现出显着的活性，IC ₅₀值分别为4.86至26.56μM。