一品红根的植物化学研究。导致了11种未描述的加仑单宁的分离,渔夫单宁A-K,连同四个已知的类似物。它们的结构由包括UV在内的全面光谱数据阐明,IR,HR-ESI-MS,和NMR,而糖部分的绝对构型通过酸水解和HPLC分析确定。FishertanninA拥有一个不寻常的骨骼,由苯乙酮组成,没食子酰基,阿拉伯呋喃基和吡喃葡萄糖基部分。FishertanninB,渔夫丹宁H,渔夫丹宁K,1,2,3-三-O-没食子酰-β-D-吡喃葡萄糖,3,4,6-三-O-没食子酰-D-吡喃葡萄糖,和1,6-二-O-没食子酰-β-D-吡喃葡萄糖显示出有效的α-葡萄糖苷酶抑制活性,IC50值为15.48-177.13μM。结构-活性关系(SAR)的检查表明,没食子酰和吡喃葡萄糖基部分在α-葡萄糖苷酶和α-淀粉酶抑制活性的抑制活性中起关键作用。在所有分离物中,1,2,3-三-O-没食子酰-β-D-吡喃葡萄糖对α-葡萄糖苷酶显示出最有效和高度特异性的抑制活性,IC50值为15.48±0.60μM。1,2,3-三-O-没食子酰-β-D-吡喃葡萄糖的动力学分析揭示了对α-葡萄糖苷酶的混合抑制类型,分子对接显示了与α-葡萄糖苷酶(pdb3A4A)催化袋的稳定结合。这些发现表明,来自费氏大肠杆菌的gallotannins具有出色的抗糖尿病潜力,而1,2,3-三-O-没食子酰-β-D-吡喃葡萄糖可以被开发为治疗2型糖尿病的有希望的候选药物,副作用较少。
A phytochemical investigation of the roots of Euphorbia fischeriana Steud. led to the isolation of eleven undescribed gallotannins, fishertannins A-K, together with four known analogues. Their structures were elucidated by the comprehensive spectroscopic data including UV, IR, HR-ESI-MS, and NMR, while the absolute configurations of the sugar moiety were determined by the acid hydrolysis and HPLC analyses. Fishertannin A possessed an unusual skeleton comprised of acetophenone, galloyl group, arabinofuranosyl and glucopyranosyl moieties. Fishertannin B, fishertannin H, fishertannin K, 1,2,3-tri-O-galloyl-β-D-glucopyranose, 3,4,6-tri-O-galloyl-D-glucopyranose, and 1,6-di-O-galloyl-β-D-glucopyranose displayed the potent α-glucosidase inhibitory activities with the IC50 values of 15.48-177.13 μM. Examination of the structure-activity relationships (SAR) demonstrated that the galloyl and glucopyranosyl moieties played a key role in the inhibitory activity for both α-glucosidase and α-amylase inhibitory activity. Among all isolates, 1,2,3-tri-O-galloyl-β-D-glucopyranose showed the most potent and highly specific inhibitory activity against α-glucosidase with an IC50 value of 15.48 ± 0.60 μM. The kinetic analysis of 1,2,3-tri-O-galloyl-β-D-glucopyranose disclosed the mixed inhibition type on α-glucosidase, and the molecular docking visualized the stable binding with the catalytic pocket of α-glucosidase (pdb 3A4A). These findings indicated the excellent antidiabetic potential of the gallotannins from E. fischeriana, while 1,2,3-tri-O-galloyl-β-D-glucopyranose could be developed as a promising candidate for the treatment of T2DM with fewer side effects.