Regioselective O-Derivatization of Quercetin via Ester Intermediates. An Improved Synthesis of Rhamnetin and Development of a New Mitochondriotropic Derivative
作者:Andrea Mattarei、Lucia Biasutto、Federico Rastrelli、Spiridione Garbisa、Ester Marotta、Mario Zoratti、Cristina Paradisi
DOI:10.3390/molecules15074722
日期:——
characterization of the two isomeric tetraacetyl quercetin derivatives was obtained by combined HSQC and HMBC 2D-NMR analysis. These molecules can be used as starting materials for the regioselective synthesis of other derivatives. High yield syntheses of the natural polyphenol rhamnetin (7-O-methylquercetin) and of the new mitochondriotropic compound 7-(4-triphenylphosphoniumbutyl) quercetin iodide are reported
The regioselective synthesis of several quercetin (3,3',4',5,7-pentahydroxy flavone) tetraesters bearing a single free OH on 5-C was achieved in good yield by proper choice of reaction conditions using common esterification procedures. 通过咪唑促进的相应五酯的脱酰基作用,选择性地获得了在 7-C 上带有游离 OH 的四乙酰化槲皮素。通过结合 HSQC 和 HMBC 2D-NMR 分析,获得了两种异构四乙酰槲皮素衍生物的明确结构表征。这些分子可用作其他衍生物的区域选择性合成的起始材料。作为例子报道了天然多酚鼠李素(7-O-甲基槲皮素)和新的线粒体化合物7-(4