Synthesis and biological evaluation of 131I-labelled pyronaridine

I-131-Labelled pyronaridine, an antimalarial drug was synthesized and evaluated for its stability and biodistribution in rabbits. We observed that there was > 99% yield of the labelled compound as determined by HPLC and radio-TLC in our study. Dynamic imaging studies in rabbits showed that I-131-labelled pyronaridine was not concentrated in the thyroid for up to 30 min as that of (NaI)-I-131. Biodistribution studies in the blood, liver, heart, spleen, kidney and lung of rats revealed that the maximum percentage of the injected dose (%ID) and the percentage of the injected dose per gram organ weight (%ID/g) of I-131-labelled pyronaridine was found in the blood and liver when compared to the other organs even after 6 days of the drug administration. Results suggest that I-131-labelled pyronaridine can be effectively used as an imaging agent to study the metabolism and mode of a response of pyronaridine. Copyright (c) 2007 John Wiley & Sons, Ltd.