Easy access to various natural keto polyunsaturated fatty acids and their corresponding racemic alcohols
1Laboratoire de Bioinorganique Structurale, Case 432, UMR CNRS 6517 Chimie, Biologie et Radicaux libres, Faculté des Sciences de St Jérôme, Marseille Cedex 20, France. gilles.iacazio@univ.u-3mrs.fr
Abstract:
Various optically active hydroxy derivatives of polyunsaturated fatty acids were easily oxidised to their corresponding keto derivatives using Dess-Martin periodinane. The reaction was run on the millimolar scale with good yields and without appreciable isomerisation of the surrounding double bonds. Reduction of these keto compounds to yield back the starting alcohols, but now as racemic mixtures, was also conducted using CeCl(3)-NaBH(4), once again without noticeable modification of the stereochemistry of the double bonds. These reactions proved the usefulness of the chemoenzymatic access to oxylipins through the use of lipoxygenases with various regiospecificity, combined with chemical transformations of the formed hydro(pero)xides.
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