6084-72-6

Upstream product

• 112-63-0 Methyl linoleate 
• 186581-53-3 diazomethane 
• 60-33-3 linoleic acid 

Relevant academic research and scientific papers

A non-canonical caleosin from Arabidopsis efficiently epoxidizes physiological unsaturated fatty acids with complete stereoselectivity

In plants, epoxygenated fatty acids (EFAs) are constituents of oil seeds as well as defence molecules and components of biopolymers (cutin, suberin). While the pleiotropic biological activities of mammalian EFAs have been well documented, there is a paucity of information on the physiological relevance of plant EFAs and their biosynthesis. Potential candidates for EFA formation are caleosin-type peroxygenases which catalyze the epoxidation of unsaturated fatty acids in the presence of hydroperoxides as co-oxidants. However, the caleosins characterized so far, which are mostly localized in seeds, are poor epoxidases. In sharp contrast, quantitative RT-PCR analysis revealed that PXG4, a class II caleosin gene, is expressed in roots, stems, leaves and flowers of Arabidopsis. Expressed in yeast, PXG4 encodes a calcium-dependent membrane-associated hemoprotein able to catalyze typical peroxygenase reactions. Moreover, we show here that purified recombinant PXG4 is an efficient fatty acid epoxygenase, catalyzing the oxidation of cis double bonds of unsaturated fatty acids. Physiological linoleic and linolenic acids proved to be the preferred substrates for PXG4; they are oxidized into the different positional isomers of the monoepoxides and into diepoxides. An important regioselectivity was observed; the C-12,13 double bond of these unsaturated fatty acids being the least favored unsaturation epoxidized by PXG4, linolenic acid preferentially yielded the 9,10-15,16-diepoxide. Remarkably, PXG4 catalyzes exclusively the formation of (R),(S)-epoxide enantiomers, which is the absolute stereochemistry of the epoxides found in planta. These findings pave the way for the study of the functional role of EFAs and caleosins in plants. 2012 The Authors Journal compilation

Epoxidation of polyunsaturated fatty acid double bonds by dioxirane reagent: Regioselectivity and lipid supramolecular organization

The use of dimethyldioxirane (DMD) as the epoxidizing agent for polyunsaturated fatty acids was investigated. With fatty acid methyl esters, this is a convenient method for avoiding acidic conditions, using different solvents, and simplifying the isolation procedures, with less contamination due to by-products. The reagent was also tested with free fatty acids in water. In this case, the supramolecular organization of fatty acids influenced the reaction outcome, and the epoxidation showed interesting regioselective features. The C=C bonds closest to the aqueous-micelle interface is the most favored for the interaction with dimethyldioxirane. The preferential epoxidation of linoleic acid (=(9Z,12Z)-octadeca-9,12-dienoic acid) to the 9,10-monoepoxy derivative was achieved, with a high yield and 65% regioselectivity. In case of arachidonic acid (=(5Z,8Z,11Z,14Z)-eicosa-5,8,11,14-tetraenoic acid) micelles, the regioselective outcome with formation of the four possible monoepoxy isomers was studied under different conditions. It resulted to be a convenient synthesis of 'cis-5,6-epoxyeicosatrienoic acid' (=3-[(2Z,5Z,8Z)-tetradeca-2,5,8- trienyl]oxiran-2-butanoic acid), whereas in reverse micelles, epoxidation mostly gave 'cis-14,15-epoxyeicosatrienoic acid (= (5Z,8Z,11Z)-13-(3-pentyloxiran-2- yl)trideca-5,8,11-trienoic acid).