Epoxyoxoene fatty esters: key intermediates for the synthesis of long-chain pyrrole and furan fatty esters

Article abstract of DOI:10.1016/0009-3084(95)02449-S

The reaction of epoxyoxoene fatty esters, methyl (Z)-9,10-epoxy-13-oxo-(E)-11-octadecenoate (1) and methyl (Z)-12,13-epoxy-9-oxo-(E)-10-octadecenoate (2), with glycine methyl ester in the presence of a basic resin was studied to establish if these compounds might be useful intermediates in the preparation of long-chain pyrrole fatty esters.Production of C18 pyrrole fatty esters and fragmentation products with the pyrrole ring were isolated and identified in the reaction.In addition, furanoid derivatives with analogous structures were also detected and identified.Formation of these last compounds was induced by the basic resin and the same compounds were also produced in a reaction mixture incubated in the absence of the amino acid.The results found in this study show that epoxyoxoene fatty esters 1 and 2 may be used in the preparation of both long-chain pyrrole and furan fatty acids.Although their existence in nature is as yet unclear, the mass spectra results obtained in this study provide the basis for detection and identification of this type of long-chain pyrrole and furan fatty acids by gas chromatography coupled with mass spectrometry.Keywords: Long-chain pyrrole fatty esters; Long-chain furanoid fatty acids; Carbonyl-amine reactions; Oxidized lipids/amino acids reactions; Lipid peroxidation products; Non-enzymatic browning reactions