Aldehydic lipid peroxidation products derived from linoleic acid.
Lipid peroxidation (LPO) processes observed in diseases connected with inflammation involve mainly linoleic acid. Its primary LPO products, 9-hydroperoxy-10,12-octadecadienoic acid (9-HPODE) and 13-hydroperoxy-9,11-octadecadienoic acid (13-HPODE), decompose in multistep degradation reactions. These reactions were investigated in model studies: decomposition of either 9-HPODE or 13-HPODE by Fe(2+) catalyzed air oxidation generates (with the exception of corresponding hydroxy and oxo derivatives) identical products in often nearly equal amounts, pointing to a common intermediate. Pairs of carbonyl compounds were recognized by reacting the oxidation mixtures with pentafluorobenzylhydroxylamine. Even if a pure lipid hydroperoxide is subjected to decomposition a great variety of products is generated, since primary products suffer further transformations. Therefore pure primarily decomposition products of HPODEs were exposed to stirring in air with or without addition of iron ions. Thus we observed that primary products containing the structural element R-CH=CH-CH=CH-CH=O add water and then they are cleaved by retroaldol reactions. 2,4-Decadienal is degraded in the absence of iron ions to 2-butenal, hexanal and 5-oxodecanal. Small amounts of buten-1,4-dial were also detected. Addition of m-chloroperbenzoic acid transforms 2,4-decadienal to 4-hydroxy-2-nonenal. 4,5-Epoxy-2-decenal, synthetically available by treatment of 2,4-decadienal with dimethyldioxirane, is hydrolyzed to 4,5-dihydroxy-2-decenal.
Spiteller
P
P
Lehrstuhl Organische Chemie I, Universität Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany.
Kern
W
W
Reiner
J
J
Spiteller
G
G
D000388:Air; D000447:Aldehydes / Q000032:analysis* / Q000138:chemical synthesis; D001161:Arteriosclerosis / Q000378:metabolism; D002413:Cations, Divalent; D002851:Chromatography, High Pressure Liquid; D004852:Epoxy Compounds / Q000032:analysis* / Q000138:chemical synthesis; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D006898:Hydroxylamines; D007501:Iron; D019787:Linoleic Acid / Q000737:chemistry* / Q000378:metabolism; D008041:Linoleic Acids / Q000737:chemistry; D015227:Lipid Peroxidation; D008054:Lipid Peroxides / Q000737:chemistry; D008084:Lipoxygenase / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D015394:Molecular Structure; D010084:Oxidation-Reduction; D005466:Fluorocarbons
D000447:Aldehydes; D002413:Cations, Divalent; D004852:Epoxy Compounds; D006898:Hydroxylamines; D007501:Iron; D019787:Linoleic Acid; D008041:Linoleic Acids; D008054:Lipid Peroxides; D008084:Lipoxygenase; C096140:4,5-epoxy-2-decenal; C038649:13-hydroperoxy-9,11-octadecadienoic acid; C057349:2,4-decadienal; C010277:Florox Reagent; D005466:Fluorocarbons; C049606:9-hydroperoxy-11,12-octadecadienoic acid