Nine new and eleven known phorbol esters were isolated from an acetone extract of the seeds of Croton tiglium. Their structures were determined by extensive analysis of spectroscopic data. Eleven of these compounds were evaluated for their inhibition activity on human tumor cell lines HL-60 and lung carcinoma A549. 12-O-Tiglylphorbol-13-acetate (11), 12-O-(2-methyl)-butyrylphorbol-13-aetate (12), and 12-O-tiglylphorbol-13-isobutyrate (13) exhibited strong inhibition activity against both HL-60 and A549 cell lines with IC50 values ≤ 0.02 and ≤ 0.1 µg/mL, respectively. Compound 18 showed strong inhibition activity against the HL-60 cell line with an IC50 value of 0.02 µg/mL.

中文翻译：

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巴豆种子中细胞毒性佛波酯的分离和结构表征

九个新的和十一个已知的佛波酯是从巴豆的种子的丙酮提取物中分离出来的。它们的结构是通过对光谱数据的广泛分析确定的。评估了这些化合物中的 11 种对人肿瘤细胞系 HL-60 和肺癌 A549 的抑制活性。12-O-Tiglylphorbol-13-acetate (11)、12-O-(2-methyl)-butyrylphorbol-13-aetate (12) 和 12-O-tiglylphorbol-13-isobutyrate (13) 对HL-60 和 A549 细胞系的 IC50 值分别≤ 0.02 和 ≤ 0.1 µg/mL。化合物18对HL-60细胞系显示出很强的抑制活性，IC50值为0.02 µg/mL。