Technetium-99m-labeling and synthesis of thymidine analogs: Potential candidates for tumor imaging

The technetium-99m-labeling and synthesis of a series of thymidine analogs were studied. The target molecules were obtained by using 6-hydrazinopyridine-3-carboxylic acid (HYNIC) as a bifunctional coupling agent and using N-(2-hydroxy-1,1-bis(hydroxymethyl)ethyl)glycine (tricine) and ethylenediamine-N,N′-diacetic acid (EDDA) as coligands. The effects of different spacers between thymidine analog with HYNIC on radiochemical yield were also studied.