Title
NMR and molecular mechanics study of pyrethrins I and II
Document Type
Article
Publication Date
8-1-1999
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 1H and 13C 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 1H-1H 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 (CDC13) solution.
Publication Source (Journal or Book title)
Journal of Agricultural and Food Chemistry
First Page
3402
Last Page
3410
Recommended Citation
Rugutt, J., Henry, C., Franzblau, S., & Warner, I. (1999). NMR and molecular mechanics study of pyrethrins I and II. Journal of Agricultural and Food Chemistry, 47 (8), 3402-3410. https://doi.org/10.1021/jf980660b