Synthesis of N-Succinimidyl-5-(Tributylstannyl)-3-Pyridinecarboxylate(SPC) and Its Iodination

In order to alleviate the in vivo deiodination of radioiodine-labeled biomolecules, a novel precursor, N-succinimidyl-5-(tributylstannyl)-3-pyridinecarboxylate(SPC),is synthesized in an oxygen and waterfree argon atmosphere.After optimization of the synthetic experimental conditions the SPC yield reaches 45％. The product is characterized by ¹H NMR and MS. N-succinimidyl-5-iodo-3-pyridinecarboxylate(SIPC ) is also synthesized as a standard reference material. ¹²⁵I labeled SPC is prepared with a labeling rate better than 80% and radiochemical purity higher than 97% after HPLC purification. The radiochemical purity remains over 92% after 24h storage at 4℃.