Marine fatty acids

The third family of prostaglandins, based on the marine fatty acid precursor eicosapentaenoic acid, was synthesized with the help of a number of new methods designed for the introduction of the doubly unsaturated omega chain. 

The unsaturation in marine fatty acids is generally on the middle-carbons of the 16 to 22 carbon chains, that is, on C-9, 12, 15, and so on. Cross-linking leaves the carboxyl end relatively unhindered and free. Three predictable consequences of this are ... 

RECENT DEVELOPMENTS IN THE TOTAL SYNTHESIS OF BIO ACTIVE MARINE FATTY ACIDS... 

Marine fatty acids continue to occupy a central role in modem marine natural products research because of the unusual array of structural motifs constantly being discovered. Most novel fatty acids were identified in marine invertebrates or marine microorganisms. Although excellent reviews of the syntheses of terrestrial fatty acids are published frequently and several outstanding reviews about the chemistry of fatty acids have appeared recently [1], there has been no review of the synthetic methodology used in the preparation of marine fatty acids. Therefore, this review presents a compilation of what has been published recently regarding the synthesis of unusual marine fatty acids, some of... 

Partial syntheses have been preferred because the desired trimethylated marine fatty acids can be related to similar isoprenoid natural products that could be used as starting materials for the syntheses. 

The 7-methyl-6-hexadecenoic acid is a ubiquitous marine fatty acid first reported from whale oils by both Pascal and Ackman, and Sano [23-24]. However, most recently both Z and E stereoisomers have been identified... 

Recent developments in the total synthesis of bioactive marine fatty acids 63... 

Ackman, R.G., Jangaard, P.M., Hoyle, R.J., and Brockerhoff, H. 1964. Origin of marine fatty acids. Analysis of the fatty acids produced by the diatom Skeletonema costatum. J. Fish Res. Bd. Can. 21, 747-756. 

An experimental study reported a CLA level of 1.6 mg/g fat in the liver and 0.6 mg/g fat in the muscle of juvenile yellow perch, even though CLA was absent in then-diet (59). However, Ackman (60) could not detect any CLA in farmed carp, tilapia, and rockfish. It is interesting to note that Chin et al. (10) did not detect the cis-9, trans-11-isomer in CLA from any of their marine samples. Ackman (60), an authority on marine lipids, points out that during chromatographic analysis, the marine fatty acids 18 4n-3 and 18 4n-l elute in the region that CLA isomers occupy. Thus the CLA values recorded for marine products may be due to these 18 4 fatty acids and not CLA itself. With increasing reliance on aquaculture worldwide, the future may see some CLA in marine products if ruminant-derived ingredients are used in their feed. 

Woods, R.K., Thien, F.C.K., and Abramson, M.J., Dietary marine fatty acids (fish oil) for asthma in adults and children, in The Cochrane Library, Issue 2, Update Software, Oxford, United Kingdom, 2003. 

Carballeira, N.M., Emiliano, A Hernandez-Alonso, N., and Gonzalez, F.A. (1998) Facile total synthesis and antimicrobial activity of the marine fatty acids (Z)-2-metho3gr-5-hexadecenoic add and (Z)-2-methoxy-6-hexadecenoic acid. J. Nat. Prod., 61,1543-1546. 

Carballeira, N.M. and Miranda, C. (2003) The first total synthesis of the marine fatty acid ( )-9-methoxypentadecanoic acid a synthetic route towards mid-chain methoxylated fatty acids. Chem. Phys. Lipids, 124, 63-67. 

Carballeira, N.M., Montano, N., Balaiia-Fouce, R., and Fernandez Prada, C. (2009) First total synthesis and antiprotozoal activity of Z-17-mefhyl-13-octadecenoic add, a new marine fatty acid from the sponge Polymastia penicillus. Chem. Phys. Lipids, 161, 38-43. 

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