作者:Ali Mahmoud El-Halawany、Mi Hwa Chung、Norio Nakamura、Chao-Mei Ma、Tsutomu Nishihara、Masao Hattori
DOI:10.1248/cpb.55.1476
日期:——
Through an estrogenic activity bioassay-guided fractionation of the 70% ethanolic extract of Cassia tora seeds two new phenolic triglucosides, torachrysone 8-O-[β-D-glucopyranosyl(1→3)-O-β-D-glucopyranosyl(1→6)-O-β-D-glucopyranoside] (1) and toralactone 9-O-[β-D-glucopyranosyl-(1→3)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranoside] (2), along with seven known compounds were isolated. The structures of the new compounds were elucidated on the basis of spectroscopic and chemical evidence. The estrogenic activity of the fractions and the isolated compounds were investigated using the estrogen-dependent proliferation of MCF-7 cells. In addition, the yeast two hybrid assay expressing estrogen receptor α (ERα) and β (ERβ) and the ERα competitor screening assay (ligand binding screen) were used to verify the binding affinities of the isolated compounds to ER. Furthermore, a naringinase pre-treatment of the 70% alcoholic extract of Cassia tora seeds resulted in a significant increase in its estrogenic activity. From the naringinase pre-treated extract six compounds were isolated, among which 6-hydroxymusizin and aurantio-obtusin showed the most potent estrogenic activity, while torachrysone, rubrofusarin and toralactone showed a significant anti-estrogenic activity. Finally, the structure requirements responsible for the estrogenic activity of the isolated compounds were studied by investigating the activity of several synthetic compounds and chemically modifying the isolated compounds. The basic nucleus 1,3,8-trihyroxynaphthalene (T3HN) was found to play a principal role in the binding affinity of these compounds to ER.
通过对决明子 70%乙醇提取物进行雌激素活性生物测定引导分馏,获得了两种新的酚类三葡糖苷,即 torachrysone 8-O-[β-D-glucopyranosyl(1→3)-O-β-D-glucopyranosyl(1→6)-O-β-D-glucopyranoside] (1) 和 toralactone 9-O-[β-D-glucopyranosyl-(1→3)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranoside] (2)(1) 和环内酯 9-O-[β-<小>D小>-吡喃葡萄糖基-(1→3)-O-β-<小>D小>-吡喃葡萄糖基-(1→6)-O-β-<小>D小>-吡喃葡萄糖苷]。(2) 和七个已知化合物被分离出来。根据光谱和化学证据,阐明了新化合物的结构。利用 MCF-7 细胞的雌激素依赖性增殖法研究了馏分和分离化合物的雌激素活性。此外,还采用了表达雌激素受体α(ERα)和β(ERβ)的酵母双杂交试验和ERα竞争者筛选试验(配体结合筛选)来验证分离化合物与ER的结合亲和力。此外,决明子 70% 酒精提取物经柚皮苷酶预处理后,其雌激素活性显著提高。从柚皮苷酶预处理提取物中分离出了六种化合物,其中 6-hydroxymusizin 和 aurantio-obtusin 的雌激素活性最强,而 torachrysone、rubrofusarin 和 toralactone 的抗雌激素活性明显。最后,通过研究几种合成化合物的活性和对分离出的化合物进行化学修饰,研究了导致分离出的化合物具有雌激素活性的结构要求。研究发现,1,3,8-三羟基萘(T3HN)基本核对这些化合物与雌激素的结合亲和力起主要作用。