Chemical C2-elongation of polyunsaturated fatty acids.
Three fatty acids were synthesized from commercially available alpha-linolenic, stearidonic and eicosapentaenoic acids by C2-elongation using a four step preparative technique. The parent fatty acid methyl esters were reduced to alcohols with LiAlH(4), converted to bromides by treatment with triphenylphosphine dibromide, coupled with a lithiated C2-elongation block--2,4,4-trimethyl-2-oxazoline--to form the corresponding 2,2-dimethyloxazolines of C2-elongated fatty acids, and finally, converted to the target polyunsaturated fatty acids by acidic alcoholysis. Yields of more than 60% were achieved on a gram scale. The resulting 11Z,14Z,17Z-eicosatrienoic, 8Z,11Z,14Z,17Z-eicosatetraenoic and 7Z,10Z,13Z,16Z,19Z-docosapentaenoic acids were obtained as colorless oils with >98% purity and could be used for biochemical investigations without additional purification. The elongated fatty acids were free of byproducts that could result from Z-E isomerization or migration of double bonds.
Kuklev
Dmitry V
DV
Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
Smith
William L
WL
D000433:1-Propanol / Q000737:chemistry; D019342:Acetic Acid / Q000737:chemistry; D000586:Amination; D005231:Fatty Acids, Unsaturated / Q000737:chemistry*; D008745:Methylation; D015394:Molecular Structure; D010080:Oxazoles / Q000138:chemical synthesis / Q000737:chemistry
D005231:Fatty Acids, Unsaturated; D010080:Oxazoles; C064210:oxazolidine; D000433:1-Propanol; D019342:Acetic Acid