Synthesis, purification, and in vitro stability of At-211- and I-125-labeled amidobisphosphonates

A method is described for preparing At-211- and radioiodinated amidobisphos phonates. The active esters N-succinimidyl 3-(tri-methylstannyl) benzoate ( ATE) and N-succinimidyl 5-(tri-methylstannyl)-3-pyridinecarboxylate (SPC) w ere used as precursors. The isolated and purified radiolabeled intermediate s were coupled to 3-amino-1-hydroxypropylidene-1,1-bisphosphonate (APB) in high yields ranging from 60% to 97%. The lipophilicity of the compounds was found to depend on the nature of the labeled template and the halogen. Hig h in vitro stability in mouse, fetal calf, and human serum was documented b y high performance liquid chromatography. NUCL MED BIOL 26;4:397-403, 1999. (C) 1999 Elsevier Science Inc. All rights reserved.