从卫矛科植物南蛇藤CelastrusorbiculatusThunb．根的石油醚提取物中分得8个单体化合物。经化学方法和光谱分析，其中5个化合物分别鉴定为扁蒴藤素（Pristimerin，Ⅰ），β-谷甾醇（Ⅱ），β-香树脂醇（β-amyrin，Ⅲ），β-香树脂醇棕榈酸酯（β-amyrinpalmitate，Ⅳ），正三十醇乙酸酯（1－triacontanolacetate，Ⅴ）。化合物Ⅰ～Ⅴ均系首次从该植物中分得。Ⅰ经体外抗癌试验，对P_(383)细胞的IC_(50)=0．267μg／ml，对LAX细胞IC_(50)=0．018μg／ml。 From the cerambycidae south serpentine Celastrusorbiculatus Thunb. 8 monomer compounds were separated from the petroleum ether extract of the root. Chemically and spectroscopically, five compounds were identified as Pristimerin (I), β-sitosterol (II), β-amyrin (III), β-camptothecinol Palmitate (β-amyrinpalmitate, IV), 1-triacontanolacetate (V). Compounds I-V were all isolated from the plant for the first time. I In vitro anticancer assay, IC_(50)=0.267μg/ml for P_(383) cells and IC_(50)=0.018μg/ml for LAX cells.