目的 研究苦木科植物苦木Picrasma quassioides茎的化学成分。方法 运用硅胶柱色谱、Sephadex LH-20柱色谱、ODS柱色谱以及反相HPLC等多种色谱分离手段进行分离纯化,根据理化性质和现代波谱学方法鉴定化合物的结构。通过MTT法和MIC法分别评价化合物的细胞毒和抗菌活性。结果 从苦木茎95%乙醇提取物中分离得到了3个β-卡巴林生物碱成分,分别鉴定为picrasidine F(1)、picrasidine G(2)和picrasidine S(3)。化合物1对人宫颈癌HeLa细胞有显著的细胞毒活性,且选择性较强;化合物2和3对人宫颈癌HeLa细胞、胃癌MKN-28细胞和小鼠黑色素瘤B-16细胞具有显著的细胞毒活性。化合物1～3对2株耐甲氧西林金黄色葡萄球菌(MRSA)和2株甲氧西林敏感的金黄色葡萄球菌(MSSA)有显著的抑菌活性。结论 首次对化合物1的核磁数据进行了全归属。3个化合物表现出显著的细胞毒活性和抗菌活性。

Objective To study the chemical constituents from the stems of Picrasma quassioides. Methods The constituents were isolated and purified by silica gel, Sephadex LH-20, ODS column chromatographies, and preparative HPLC. Their structures were determined on the basis of their physicochemical properties and spectral data. The cytotoxic and antibacterial activities were assessed by MTT and MIC, respectively. Results Three β-carboline alkaloids were obtained from the 95% ethanol extract of the stems of P. quassioides and identified as picrasidine F (1), picrasidine G (2), and picrasidine S (3). Compound 1 showed selective cytotoxicity to HeLa cell, while compounds 2 and 3 showed the potent cytotoxicity against human HeLa cervical, gastric MKN-28, and mouse melanoma B-16 cancer cells. Compounds 1—3 showed the potent antibacterial activity against two strains of pathogenic bacteria methicillin-resistant Staphylococcus aureus (MRSA) and two strains of pathogenic bacteria methicillin-sensitive Staphylococcus aureus (MSSA). Conclusion The assignments of NMR data of compound 1 are reported in this paper for the first time. Compounds 1—3 show the potent cytotoxic and antibacterial activities.

国家自然科学基金资助项目(41476121,41106127,81302691,81172978)