Hydroxamamide as a chelating moiety for the preparation of 99mTc radiopharmaceuticals—II. The 99mTc complexes of hydroxamanide derivatives

Abstract

In a search for a basic ligand structure to coordinate with the radiometal technetium (Tc), three different hydroxamamide derivatives, benzohydroxamamide, p-toluhydroxamamide and 4-pyridylhydroxamamide were synthesized. Radiolabeling was carried out easily using the stannous tartrate method and high yields or complexes with 99mTc at room temperature over a wide pH range were obtained. The 99mTc-complexes formed with each ligand showed good stability and their organ distribution, blood clearance and urinary excretion in mice were screened. The presence of the substituted group showed little effect on the in vitro or in vivo stability of these 99mTc complexes.Thus, the hydroxamamide-based ligand may be a useful new chelating moiety for designing 99mTc radiopharmaceuticals.