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- 2002 (2)
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- Fatty acids (2) (entfernen)
Technetium- and Rhenium-Labelled Fatty Acids as Model Compounds for Myocardial Metabolism Imaging
(2002)
In an attempt to develop new technetium-based radiopharmaceuticals for the non-invasive diagnosis of oxidative myocardial metabolism, rhenium model compounds according to the 3+1' mixed ligand approach as well as the organometallic tricarbonyl-design were synthesized. The geometrical impact of different chelates on the integrity of the fatty acid head structure was determined by single crystal X-ray analyses. To evaluate the diagnostic potential of the analogous Technetium-99m compounds, fatty acid complexes of the 3+1' mixed ligand type were prepared on n.c.a.-level and studied in the isolated constant-flow-perfused guinea pig heart model; compared to established [123I]Iodine-labelled fatty acid radiotracers, the tested Technetium-99m derivatives showed a specific, however significantly lower myocardial extraction rate.
In an attempt to develop new technetium-based radiopharmaceuticals for the noninvasive diagnosis of myocardial metabolism, we have synthesized three examples of novel metal-containing fatty acid derivatives according to the 3+1 mixed-ligand and the Schiff base/tricarbonyl design. The chelates contain the metal core in the oxidation states +5 and +1, respectively, and are attached to the end-position of a fatty acid chain. The complex formation was accomplished by ligand-exchange reactions with three different rhenium precursors, whereas the inactive rhenium metal was utilized as a surrogate of the technetium radionuclide. The molecular structures of the fatty acid complexes 7, 10 and 14 were determined by single-crystal X-ray diffraction analyses and impressively show a general problem in technetium tracer research, namely the significant structural alterations of bioactive molecules by coordination even to small metal chelates.