Synthesis and preliminary biological evaluation of a technetium-99m labeled thymidine analog

The synthesis and labeling of;Tc-N;-（N’-[2-sulfanyl-ethylamino）acetyl]-2-aminoethyl-sulfanyl-1-hexanamide}thymidine (;Tc-NHT) were studied.In the presence of sodium glucoheptonate（GH） and ethylene diamine tetraacetic acid（EDTA）,;Tc-NHT was obtained by using bisaminoethanethiol（N;S;） as a bifunctional coupling agent.The radiochemical purity of the;Tc-NHT was over 95%.Biodistribution of;Tc-NHT was performed in hepatoma HepA tumor-bearing mice.At 2 h p.i.,the ratios of tumor-to-muscle,tumor-to-bone and tumor-to-blood were 4.41±0.32,2.45±0.24 and 1.51±0.18,respectively.