Effect of 3-methyl-branching on the myocardial retention of radioiodinated 19-iodo-18-nonadecenoic acid analogues

Abstract The effect of methyl-branching at the 3(β-)-position on myocardial uptake and retention of fatty acids where radioiodide has been stabilized as a terminal trans-(E)-vinyl iodide has been evaluated in fasted rats. The syntheses of two new dimethyl-branched fatty acids, 17-iodo-3,3-dimethylheptadecanoic acid (14) and (E)-19-iodo-3,3-dimethyl-18-nonadecenoic acid (19), are described. Tissue distribution studies in fasted rats with [ 125 I]-19 showed significant heart uptake (2 min, 4.56% dose/g), and prolonged retention (60 min 4.10% dose-g). These results suggest that [ 123 I]-19 is a good candidate for further studies of regional myocardial fatty acid uptake patterns by SPECT.