Wang Xiao-Ling, Jiao Fu-Rong, Yu Meng, Lin Li-Bin, Xiao Jian, Zhang Qiang, Wang Le, Duan Dong-Zhu, Xie Gang
Shaanxi Key Laboratory of Phytochemistry, College of Chemistry and Chemical Engineering, Baoji University of Arts and Sciences, Baoji 721013, Shaanxi, PR China.
Shaanxi Key Laboratory of Phytochemistry, College of Chemistry and Chemical Engineering, Baoji University of Arts and Sciences, Baoji 721013, Shaanxi, PR China.
Bioorg Med Chem Lett. 2017 May 1;27(9):1993-1998. doi: 10.1016/j.bmcl.2017.03.013. Epub 2017 Mar 7.
One new flavone hydrate named lobatflavate (1), one new chromone named lobatchrosin (2), and one new isoflavone named 3S,4R-tuberosin (3), along with four known isoflavone analogues (4-7), were isolated from the traditional Chinese medicinal plant of Pueraria lobata (Willd.) ohwi. Their structures were elucidated by extensive spectroscopic methods of IR, UV, HR-ESI-MS, 1D and 2D NMR. The absolute configuration of 3 was determined by CD spectrum associated with TD-DFT calculation analysis. All compounds except for 2 were assayed the inhibitory activity against α-glucosidase. Every tested compound was proved to be more active than positive control of acarbose. Of which 1 and 4 showed significant activity with IC value of 1.79μM and 23.01μM (IC of acarbose was 1998.79μM). Enzyme kinetic experiments revealed that 1 was irreversible whereas 4 was reversible and non-competitive α-glucosidase inhibitors. Moreover, structure-activity relationship was discussed and the docking studies of 1, 3 and 4 were also carried out.
从传统中药植物野葛（Pueraria lobata (Willd.) ohwi）中分离得到一种新的黄酮水合物，命名为野葛黄酮水合物（1）、一种新的色酮，命名为野葛色酮（2）以及一种新的异黄酮，命名为3S,4R-块茎异黄酮（3），同时还得到四种已知的异黄酮类似物（4 - 7）。通过红外光谱（IR）、紫外光谱（UV）、高分辨电喷雾电离质谱（HR-ESI-MS）、一维和二维核磁共振等广泛的光谱方法对它们的结构进行了阐明。通过与含时密度泛函理论（TD-DFT）计算分析相关的圆二色光谱（CD）确定了3的绝对构型。除2之外的所有化合物均测定了对α-葡萄糖苷酶的抑制活性。结果表明，每个测试化合物的活性均高于阳性对照阿卡波糖。其中1和4表现出显著活性，IC值分别为1.79μM和23.01μM（阿卡波糖的IC值为1998.79μM）。酶动力学实验表明，1是不可逆的，而4是可逆的非竞争性α-葡萄糖苷酶抑制剂。此外，还讨论了构效关系，并对1、3和4进行了对接研究。
