Evaluation of structure effects on the pharmacological behaviour of radioiodinated phenylpentadecanoic acids

For studying the pharmacokinetic behaviour of fatty acids with different chemical structures four 123I-labelled compounds, i.e. the ortho and para 123I-isomers of 15-phenyl-pentadecanoic acid (IPPA) and 3-methyl-15-phenylpentadecanoic acid, were prepared and the organ distribution was determined in mice. The results showed a significant decrease of the maximal heart uptake for the two ortho compounds. The hypothesis of blocked metabolism due to β-methylation was not confirmed. Both β-methylated compounds showed a biexponential elimination from the heart. (Author)