目的 研究三桠苦Melicope pteleifolia的化学成分。方法 三桠苦用80%乙醇渗漉提取，提取物用色谱技术分离，采用波谱技术（EI-MS、¹H-NMR、¹³C-NMR等）和化学方法进行结构鉴定。结果 从三桠苦乙醇提取物的石油醚部位和醋酸乙酯部位分离出4个化合物，分别鉴定为3, 5, 3′-三羟基-4′-甲氧基-7-异戊烯氧基黄酮（1）、3, 7-二甲氧基山柰酚（2）、香草酸（3）、β-谷甾醇（4）。结论 化合物1是新化合物，命名为三桠苦素C，化合物2、3为首次从该植物中分离得到。

Objective To study the constituents of Melicope pteleifolia. Methods Plant material was percolated with 80% EtOH. Compounds were separated with chromatography technology and their structures were elucidated by spectral analysis (EI-MS, ¹H-NMR, and ¹³C-NMR) and chemical evidence. Results Four compounds were isolated from petroleum ether and ethyl acetate soluble fractions. Their structures were identified as: 3, 5, 3′-trihydroxy-4′-methoxy-7-(3-methylbut-2-enyloxy) flavone (1), 3, 7- methoxyl kaempferol (2), vanillic acid (3), and β-sitosterol (4). Conclusion Compound 1 is a new compound named pteleifolosin C. Compounds 2 and 3 are isolated from this plant for the first time.