基于 NMR 和 ECD 计算与实验数据比较从 L.f. 中分离得到的对映异构的 Entcassiflavan-(4β→8)-表儿茶素的结构阐明。
Structural Elucidation of an Atropisomeric Entcassiflavan-(4β→8)-Epicatechin Isolated from L.f. Based on NMR and ECD Calculations in Comparison to Experimental Data.
机构信息
Natural Products Research Institute (IPPN), Center of Health Sciences, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro 21941-902, RJ, Brazil.
Natural Products and Food Department, Pharmacy Faculty, Center of Health Sciences, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro 21941-902, RJ, Brazil.
出版信息
Molecules. 2022 Apr 13;27(8):2512. doi: 10.3390/molecules27082512.
A rare dihydoxyflavan-epicatechin proanthocyanidin, entcassiflavan-(4β→8)-epicatechin, was isolated from , a plant widely used by traditional people from the Amazon to treat urinary tract infections. The constitution and relative configuration of the compound were elucidated by HR-MS and detailed 1D- and 2D-NMR measurements. By comparing the experimental electronic circular dichroism (ECD) spectrum with the calculated ECD spectra of all 16 possible isomers, the absolute configuration, the interflavan linkage, and the atropisomers could be determined.
从亚马逊地区的传统人群广泛用于治疗尿路感染的植物 中分离到一种罕见的二羟基黄烷-表儿茶素原花青素，entcassiflavan-(4β→8)-表儿茶素。通过高分辨质谱（HR-MS）和详细的 1D 和 2D-NMR 测量，阐明了该化合物的结构和相对构型。通过比较实验电子圆二色性（ECD）光谱与所有 16 种可能异构体的计算 ECD 光谱，确定了绝对构型、黄烷间键和对映异构体。
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