Shen Ya-Ching, Wang Chih-Hsin, Cheng Yuan-Bin, Wang Li-Tung, Guh Jih-Hwa, Chien Ching-Te, Khalil Ashraf Taha
Institute of Marine Resources, National Sun Yat-sen University, 70 Lien-Hai Road, Kaohsiung, Taiwan, Republic of China.
J Nat Prod. 2004 Mar;67(3):316-21. doi: 10.1021/np0303658.
Bioassay-guided fractionation of an EtOAc-soluble extract of Casearia membranacea has resulted in the isolation of six new clerodane diterpenes, caseamembrins A-F (1-6), and a known compound, rel-(2S,5R,6R,8S,9S,10R,18S,19R)-diacetoxy-18,19-epoxy-6-hydroxy-2-(2-methylbutanoyloxy)cleroda-3,13(16),14-triene (7). The structures of 1-6 were established on the basis of extensive 1D and 2D NMR spectroscopic analysis. In addition, the new derivatives, 8 and 9, were prepared by acylation of 7 and 3, respectively. The isolated diterpenoids and their derivatives were tested against human prostate (PC-3) and hepatoma (Hep3B) cancer cells. Compounds 1, 3-5, and 7 exhibited cytotoxicity against both tumor cells, with IC(50) values below 3 micromicro, while compounds 2, 6, 8, and 9 were less effective.
对膜叶嘉赐树乙酸乙酯可溶提取物进行生物测定导向的分级分离，已分离出六种新的克罗烷二萜类化合物，即膜叶嘉赐树素A - F（1 - 6），以及一种已知化合物，rel-(2S,5R,6R,8S,9S,10R,18S,19R)-二乙酰氧基-18,19-环氧-6-羟基-2-(2-甲基丁酰氧基)克罗达-3,13(16),14-三烯（7）。1 - 6的结构是基于广泛的一维和二维核磁共振光谱分析确定的。此外，新衍生物8和9分别通过7和3的酰化反应制备。对分离得到的二萜类化合物及其衍生物进行了针对人前列腺（PC - 3）和肝癌（Hep3B）癌细胞的测试。化合物1、3 - 5和7对两种肿瘤细胞均表现出细胞毒性，半数抑制浓度（IC(50)）值低于3微摩尔，而化合物2、6、8和9的效果较差。
