Synthesis of a technetium-99m labeled tricyclic ganciclovir analog for non-invasive reporter gene expression imaging

A potential radiopharmaceutical and HSV1-TK substrate, 3-((1,3-dihydroxypropan-2-yloxy)-methyl)-6-(4-(3-((2-mercaptoethyl)(2-(2-mercaptoethyl-amino)-ethyl)amino)propoxy)phenyl)-3H-imidazopurin-9(5H)-one-oxo-technetium(V), was synthesized via a converging approach and its chemical structure was comparatively characterized with a non-radioactive analog. The final radiochemical purity and yield were 97 and 73%, respectively.