Structural Elucidation of an Atropisomeric Entcassiflavan-(4β→8)-Epicatechin Isolated from Dalbergia monetaria L.f. Based on NMR and ECD Calculations in Comparison to Experimental Data

Molecules

Andrea Porzel¹  Wolfgang Brandt¹  Ludger A. Wessjohann¹  Roberto Carlos Campos Martins²  Patrícia Homobono Brito de Moura²  Ivana Correa Ramos Leal³ 

[1] Department of Bioorganic Chemistry, Leibniz Institute of Plant Biochemistry (IPB), Weinberg 3, 06114 Halle, Germany;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;

关键词: Dalbergia monetaria;    proanthocyanidin;    procassidin dimer;    electronic circular dichroism (ECD);    quantum chemical calculation;    NMR;   

DOI  :  10.3390/molecules27082512

来源: DOAJ

【 摘 要 】

A rare dihydoxyflavan-epicatechin proanthocyanidin, entcassiflavan-(4β→8)-epicatechin, was isolated from Dalbergia monetaria, 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.

【 授权许可】

Unknown