Wu Xiao-Peng, Han Chang-Ri, Chen Guang-Ying, Yuan Yuan, Xie Jian-Ying
Key Laboratory of Tropical Medicinal Plant Chemistry of Ministry of Education, College of Chemistry & Chemical Engineering, Hainan Normal University, Haikou, China 571158.
Nat Prod Commun. 2010 Jul;5(7):1027-30.
Four pentacyclic triterpenoids were obtained from the leaves of Combretum oliviforme Chao, 3beta-hydroxyolean-12-en-28-oic acid (1), 23-O-[alpha-L-(4'-acetylrhamnopyranosyl)]-imberbic acid (2), 23-acetoxy-3beta-acetylimberbic acid-29-methyl ester (3), and 23-O-[alpha-L-rhamnopyranosyl]-1,3beta-diacetylimberbic acid (4). Hydrolysis of 2 and 4 gave 23-hydroxyimberbic acid (5). The structures were elucidated by NMR, electrospray ionization mass spectrometry (ESIMS) and comparison with literature data. Compounds 1, 2, 3 and 4 were isolated from C. oliviforme Chao leaves for the first time and 3 for the first time from any natural source. All compounds were tested in vitro for their activity against human lung cancer cell line SPC-A-1, human erythroleukaemic line K562 and human gastric cancer SGC-7901 cells. Compounds 1, 3, 4 and 5 had cytotoxic activity for the three cell lines with IC50 0.69-69.68 microM. These results suggest that the presence of acetyl group in the triterpene aglycone structure plays an essential role for cytotoxic activity.
从榄形风车子（Combretum oliviforme Chao）的叶子中获得了四种五环三萜类化合物，分别为3β-羟基齐墩果-12-烯-28-酸（1）、23-O-[α-L-(4'-乙酰基鼠李吡喃糖基)]-硬脂酸（2）、23-乙酰氧基-3β-乙酰硬脂酸-29-甲酯（3）以及23-O-[α-L-鼠李吡喃糖基]-1,3β-二乙酰硬脂酸（4）。化合物2和4水解后得到23-羟基硬脂酸（5）。通过核磁共振（NMR）、电喷雾电离质谱（ESIMS）以及与文献数据对比对其结构进行了阐明。化合物1、2、3和4首次从榄形风车子的叶子中分离得到，化合物3首次从任何天然来源中分离得到。所有化合物均在体外测试了对人肺癌细胞系SPC-A-1、人红白血病细胞系K562以及人胃癌SGC-7901细胞的活性。化合物1、3、4和5对这三种细胞系具有细胞毒性活性，IC50为0.69 - 69.68微摩尔。这些结果表明三萜苷元结构中乙酰基的存在对细胞毒性活性起着至关重要的作用。
