H-1-C-13 HMBC NMR experiments as a structural and analytical tool for the characterization of elusive trans/cis hydroperoxide isomers from oxidized unsaturated fatty acids in solution

摘要

The radical-dependent oxidation of unsaturated fatty acids is a fundamental reaction in lipid chemistry, biochemistry, and technology. We report herein the first successful application of H-1-C-13 HMBC NMR experiment for the identification and quantification of complex and minor (3.9% to 0.85%) components of cis and trans primary hydroperoxide isomers of oxidized oleate and linoleate methyl esters in solution, without the need of laborious isolation of the individual components.