Fatty acid derivatives labelled

Several F-labeled fatty acid derivatives have been successfully prepared and evaluated as potential FAO assessing tracers [19-24]. Methyl-branched-chain (w- F-fluorofatty acids, such as 3-methyl-(3-MFHA) and 5-methyl-17-[ F]fluoro-heptadecanoic acid (5-MFHA), have been reported [23]. In a comparative study, it was found that rw-[ F]fluoropalmitic acid (FPA) exhibits the highest myocardial uptake, followed by 5-MFHA and 3-MFHA. FPA possesses the fastest myocardial washout rate, and 3-MFHA the slowest. In lipid analysis studies, 5-MFHA... 

Membrane and lipid General lipid and cell Lipid and fatty acid derivatives of Fluorescence labeled lipids and fatty 45... 

In contrast to radioiododeiodination, exchange of bromine with radioiodine on aromatic systems is feasible for no-carrier-added syntheses. This method was, e.g., used to label fatty acid derivatives. Thus, 13-(4-[ I]iodophenyl)-3-(p-phenylene)tridecanoic acid ([ 1]PH1PA 3-10) was prepared from the 4-bromophenyl derivative in a benzoic acid melt at an exchange temperature of200°C (Liefhold and Eisenhut 1986). However, the method is laborious because two evaporation steps are needed before exchange can take place. 

Fig. 3. Synthesis of labelled p-keto and p-hydroxy C28 fatty acid derivatives (5) and (6)...

The FT n.m.r. spectrum at 15.08 MHz of C-enriched methyl palmi-toleate (50), which was isolated from the lipid fraction, was recorded on 1.2 mg in CHCI3 solution. The spectrum showed enhanced signal intensities for the eight alternate carbon atoms (C-2, C-4, C-6, C-8, C-10, C-12, C-14, and C-16). This is the expected labelling pattern for the fatty acid derived from CH3C02Na. Mass spectrometry of the C-enriched ester indicated a 32% enrichment for the eight alternate sites. 

Macrolide aggregation pheromones produced by male cucujid beetles are derived from fatty acids. Feeding experiments with labeled oleic, linoleic, and palmitic acids indicate incorporation into the macrolide pheromone component [ 117 ]. The biosynthesis of another group of beetle pheromones, the lactones, involves fatty acid biosynthetic pathways. Japonilure and buibuilactone biosynthesized by the female scarab, Anomalajaponica, involves A9 desaturation of 16 and 18 carbon fatty acids to produce Z9-16 CoA and Z9-18 CoA,hydroxylation at carbon 8 followed by two rounds of limited chain shortening and cyclization to the lactone [118]. The hydroxylation step appears to be stereospecific [118]. 

Oxidation is a cyclical pathway which removes a C2 (acetyl) unit form the fatty acyl-CoA on each cycle. The designation [3 derives from the traditional system of labelling atoms within fatty acid molecules where the carbon attached to the carboxyl group is a and the methyl carbon is always CO (omega) ... 

The carbon chain of prostacyclin is derived from acetate by way of a C20 fatty acid. Trace a continuous chain of 20 carbons beginning with the carboxyl group. Even-numbered carbons are labeled with 14C when prostacyclin is biosynthesized from 14CH3C02H. 

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