Two new phenanthrenequinones, bulbocodioidins I–J (1 and 2), were isolated from the tubers of Pleione bulbocodioides. They possess a 9(10)H-phenanthren-10(9)-one structure, which is relatively rare from natural sources. Their structures were elucidated by extensive spectroscopic data analysis. The absolute configurations of them were determined by comparison of the experimental and calculated ECD curves. Compound 2 exhibited cytotoxic activity against human breast cancer cell lines (MCF-7) with the IC₅₀ value of 2.1 μM in vitro.

中文翻译：

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Pleione bulbocodioides的块茎中的两种具有细胞毒活性的新菲醌

从Pleione bulbocodioides的块茎中分离出两个新的菲醌，bulbodiodiins I–J（1和2）。它们具有9（10）H -phenanthren-10（9）-one结构，这在自然资源中相对较少。通过广泛的光谱数据分析阐明了它们的结构。它们的绝对构型是通过比较实验和计算出的ECD曲线确定的。化合物2对人乳腺癌细胞系（MCF-7）表现出细胞毒活性，体外IC ₅₀值为2.1μM 。