除虫菊素I和II的核磁共振与分子力学研究

NMR and molecular mechanics study of pyrethrins I and II.

作者信息

Rugutt J K, Henry C W, Franzblau S G, Warner I M

机构信息

Department of Chemistry, Louisiana State University, Baton Rouge 70803, USA.

出版信息

J Agric Food Chem. 1999 Aug;47(8):3402-10. doi: 10.1021/jf980660b.

DOI:10.1021/jf980660b

PMID:10552664

Abstract

Bioassay-directed fractionation of the organic extract of the Kenyan pyrethrum flowers (Chrysanthemum cinerariaefolium Vissiani) resulted in the isolation of two natural pyrethrin esters, pyrethrin I (PI) and pyrethrin II (PII) as the major constituents. These esters elicited inhibition of the multiple drug resistant (MDR) Mycobacterium tuberculosis. The high-field (1)H and (13)C nuclear magnetic resonance (NMR) chemical shifts of PI and PII were unequivocally assigned using modern two-dimensional (2D) proton-detected heteronuclear multiple-quantum coherence (HMQC) and heteronuclear multiple-bond correlation (HMBC) experiments. The conformations of both esters were deduced from (1)H-(1)H vicinal coupling constants and confirmed by 2D nuclear Overhauser effect spectroscopy (NOESY). Computer molecular modeling (MM) studies revealed that PI and PII molecules adopt a "love-seat" conformation in chloroform (CDCl(3)) solution.

摘要

对肯尼亚除虫菊花（白花除虫菊）的有机提取物进行生物测定导向的分级分离，结果分离出两种天然除虫菊酯，即除虫菊酯I（PI）和除虫菊酯II（PII）作为主要成分。这些酯对多重耐药结核分枝杆菌有抑制作用。利用现代二维（2D）质子检测异核多量子相干（HMQC）和异核多键相关（HMBC）实验明确指定了PI和PII的高场（1）H和（13）C核磁共振（NMR）化学位移。两种酯的构象由（1）H-（1）H邻位偶合常数推导得出，并通过二维核Overhauser效应光谱（NOESY）得到证实。计算机分子建模（MM）研究表明，PI和PII分子在氯仿（CDCl3）溶液中呈“情侣座”构象。