Facile syntheses for (5Z,9Z)-5,9-hexadecadienoic acid, (5Z,9Z)-5,9-nonadecadienoic acid, and (5Z,9Z)-5,9-eicosadienoic acid through a common synthetic route.
The delta 5,9 fatty acids (5Z,9Z)-5,9-hexadecadienoic acid, (5Z,9Z)-5,9-nonadecadienoic acid, and (5Z,9Z)-5,9-eicosadienoic acid were synthesized for the first time in four steps (9-12% overall yield) starting from commercially available 2-(2-bromoethyl)-1,3-dioxolane. The synthetic approach provided enough material to corroborate the structure and stereochemistry of (5Z,9Z)-5,9-nonadecadienoic acid which was recently identified in the flowers of Malvaviscus arboreus (Malvaceae). The novel phospholipids 1-hexadecanoyl-2-[(5Z,9Z)-5,9-eicosadienoyl]-sn-glycer o-3-phosphocholine and 1-octadecanoyl-2-[(5Z,9Z)-5,9-eicosadienoyl]-sn- glycero-3-phosphocholine were also synthesized from commercially available L-alpha-phosphatidylcholine (egg yolk) and characterized by positive ion electrospray mass spectrometry. These are the first examples of unsymmetrical phospholipids with saturated fatty acids at the sn-1 position and delta 5,9 fatty acids at the sn-2 position.
Carballeira
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NM
Department of Chemistry, University of Puerto Rico, San Juan, Puerto Rico. ncarball@upracd.upr.clu.edu
Emiliano
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Guzmán
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D000818:Animals; D005231:Fatty Acids, Unsaturated / Q000138:chemical synthesis* / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry; D009682:Magnetic Resonance Spectroscopy; D019660:Malvaceae / Q000737:chemistry; D011161:Porifera / Q000737:chemistry; D013237:Stereoisomerism
C404169:5,9-eicosadienoic acid; C404168:5,9-nonadecadienoic acid; D005231:Fatty Acids, Unsaturated; C049916:5,9-hexadecadienoic acid