三列凹顶藻中倍半萜成分的研究

Sesquiterpene components of Laurencia tristicha

目的从三列凹顶藻Laurencia tristicha中寻找具有多样性结构的倍半萜化学成分，供药理活性筛选。方法采用凝胶柱色谱、硅胶柱色谱、重结晶和高效液相色谱等方法进行分离；借助包括一维和二维NMR等波谱方法和X-单晶衍射鉴定化合物的结构；用MTT法对得到的化合物进行细胞毒活性评价。结果分离得到5个倍半萜类化合物，分别鉴定为海兔阿普里素（aplysin，Ⅰ）、海兔阿普里醇（aplysinol，Ⅱ）、去溴海兔阿普里醇（debromoaplysinol，Ⅲ）、凹顶藻联苯（1aurebiphenyl，Ⅳ）、约翰斯顿醇（johnstonol，Ⅴ）；在人肿瘤细胞株HCT-8、Bel-7402、BGc-823、A549和HeLa模型上，化合物Ⅳ对所有细胞株均显示毒性，化合物Ⅲ对HeLa细胞显示中等强度的细胞毒活性，其他化合物对所有细胞株均无明显毒性，IC50均大于10．0μg／mL。结论化合物Ⅰ～Ⅴ均为首次从三列凹顶藻中得到，化合物Ⅲ对HeLa细胞具有中等强度的选择性细胞毒活性，化合物Ⅳ对所有细胞株均显示毒性。

Objective To search for sesquiterpene components with structural diversity from Laurencia tristicha to supply for pharmacological activity screen. Methods Compounds were isolated by means of column chromatography over normal phase silica gel and Sephadex LH-20, recrystallization, and HPLC. Structures were identified by spectroscopic methods including 1D and 2D NMR, IR, X-ray, and MS. Cytotoxicities of the purified compounds were evaluated by MTT method. Results Five sesquiterpenes, aplysin （ Ⅰ ）, aplysinol （ Ⅱ）, debromoaplysinol （ Ⅲ ）, laurebiphenyl （ Ⅳ ）, and johnstonol （ Ⅴ ） have been isolated and identified. In the cytotoxic assay compound Ⅳ was active against human cancer cell lines, HCT-8, Bel-7402, BGc-823, A549, and HeLa with IC50 values of 1.77, 1.91, 1.22, 1.68, and 1.61μg/ mL, respectively. Compound Ⅲ showed cytotoxicity against HeLa with IC50 value of 3.6μg/mL while other compounds were inactive （IC50〉10μg/mL）. Conclusion Compounds Ⅰ- Ⅴ are isolated from L. tristicha for the first time. Compound Ⅲ shows moderate selective cytotoxicity against HeLa cell line and compound Ⅳ is cytotoxicity against several human cancer cell lines.