三种密切相关的倍半萜内酯的详细1H和13C NMR结构归属及相对立体化学测定

Detailed 1H and 13C NMR structural assignment and relative stereochemistry determination for three closely related sesquiterpene lactones.

作者信息

Heleno Vladimir Constantino Gomes, de Oliveira Kleber Thiago, Lopes João Luis Callegari, Lopes Norberto Peporine, Ferreira Antonio Gilberto

机构信息

Departamento de Química, Centro de Ciências Exatas e de Tecnologia, Universidade Federal de São Carlos, Via Washington Luiz, km 235, 13565-905, São Carlos, SP, Brazil.

出版信息

Magn Reson Chem. 2008 Jun;46(6):576-81. doi: 10.1002/mrc.2220.

DOI:10.1002/mrc.2220

PMID:18357570

Abstract

A complete analysis of (1)H and (13)C NMR spectra of the trypanocidal sesquiterpene lactone eremantholide C and two of its analogues is described. These structurally similar sesquiterpene lactones were submitted to (1)H NMR, (13)C {(1)H} NMR, gCOSY, gHSQC, gHMBC, J-resolved and DPFGSE-NOE NMR techniques. The detailed analysis of those results, correlated to some computational calculations (molecular mechanics), led to the total and unequivocal assignment of all (1)H and (13)C NMR data. The determination of all (1)H/(1)H coupling constants and all signal multiplicities, together with the elimination of previous ambiguities were also achieved.

摘要

本文描述了对杀锥虫倍半萜内酯艾里曼内酯C及其两种类似物的¹H和¹³C NMR光谱的完整分析。这些结构相似的倍半萜内酯进行了¹H NMR、¹³C{¹H} NMR、gCOSY、gHSQC、gHMBC、J分辨和DPFGSE-NOE NMR技术分析。将这些结果与一些计算计算（分子力学）相关联进行详细分析，从而实现了对所有¹H和¹³C NMR数据的全面且明确的归属。还确定了所有¹H/¹H耦合常数和所有信号多重性，并消除了先前的模糊性。