7-O-葡萄糖醛酸基芒果苷的半合成（英文）

Semi-synthesis of mangiferin-7-O-β-D-glucuronide

芒果苷类天然产物是一类具有呫吨酮碳苷结构的天然植物多酚类化合物,具有广泛的生物活性,有良好的应用前景。目前,由于芒果苷类天然产物药理活性的作用机理尚不明确,对于芒果苷代谢产物进行研究具有一定意义,一方面可以进一步探究芒果苷发挥广泛生物活性的作用机制,另一方面也可促进具有较好活性的芒果苷衍生物的开发与应用。其中,7-O-葡萄糖醛酸基芒果苷是一种在动物体内分离得到的芒果苷代谢产物,由于其天然存在较少,对其化学合成方法进行研究可为对此代谢产物的生物活性探究奠定基础。本文发展了由天然较易获得的芒果苷为原料合成7-O-葡萄糖醛酸基芒果苷的新方法,在此合成路线中,采用多步连续的区域选择性保护策略,对芒果苷中的多羟基结构进行选择性修饰,之后利用相转移催化条件实现了糖苷键的构建。整条合成路线共经过10步反应,成功实现了7-O-葡萄糖醛酸基芒果苷的高效合成。

Mangiferin is a natural plant polyphenol with a structure of xanthone C-glycoside and it displays a wide spectrum of pharmacological activities. Investigation of the metabolites of mangiferin is valuable in studying the mechanisms of its various pharmacological properties and developing novel drugs from the mangiferin derivatives. Among the metabolites of mangiferin, mangiferin-7-O-β-D-glucuronide has been reported as the phase Ⅱ metabolite of mangiferin. Herein we described the first semi-synthesis of mangiferin-7-O-β-D-glucuronide with the natural product mangiferin as the starting material. In this work, we adopted several regioselective protection procedures to distinguish the different hydroxyl groups in the structure of mangiferin, and we accomplished the glycosylation under the phase-transfer catalysis conditions. In this method, we efficiently synthesized the glucuronide derivative of mangiferin in 10 steps with highly regioselective protection.