目的 分离箭叶淫羊藿中的化学成分并对8-异戊烯基黄酮类化合物进行体外抗肿瘤活性筛选。方法 采用硅胶柱色谱、凝胶柱色谱和HPLC制备色谱方法分离纯化，根据理化性质和波谱分析方法鉴定其结构，利用MTT法对分离得到的异戊烯基黄酮类化合物进行体外抗肿瘤活性筛选。结果 分离得到7个黄酮类化合物，分别鉴定为淫羊藿苷（1）、淫羊藿素（2）、宝藿苷Ⅰ（3）、去甲淫羊藿素（4）、苜蓿素（5）、淫羊藿次苷Ⅰ（6）和朝藿定C（7）。体外抗肿瘤结果表明，在0.5～100 μmol/L浓度，化合物2、3、4、6对人乳腺癌MDA-MB-231细胞增殖具有明显抑制作用，并随浓度的增加抑制作用更加明显，48 h的IC50分别为12.43、35.44、11.53、16.31 μmol/L，化合物1、7活性很弱。结论 化合物3、4为首次从箭叶淫羊藿植物分离得到，化合物3有望成为靶向抗乳腺癌的候选药物。

Objective To investigate the chemical constituents from Epimedium sagittatum and screen in vitro antitumor activity for 8-prenylated flavonoids. Methods Chemical constituents were isolated and purified by chromatography on silica gel, Sephadex LH-20 colums, and preparative HPLC. Their structures were identified by physicochemical constants and spectroscopic methods. The in vitro antitumor activities of the isolated prenylated compounds were evaluated by MTT assay. Results Seven flavonoids were isolated and their structures were identified as icariin (1), icaritin (2), baohuosideⅠ (3), desmethylicaritin (4), tricin (5), IcarisideⅠ (6), and epimedin C (7). In vitro antitumor results showed that compounds 2－4 and 6 showed the enhanced inhibition on the cell proliferation of human breast cancer cell line MDA-MB-231 in 0.5 — 100 μmol/L with concentration increasing. The IC50 value for 48 h was 12.43, 35.44, 11.53, and 16.31 μmol/L respectively, the activity of compound 1 and 7 were very weak. Conclusion Compounds 3 and 4 are isolated from E. sagittatum for the first time. Compound 3 is expected to become one of the anti-breast cancer drug candidates.