An octadentate bis(semicarbazone) macrocycle: a potential chelator for lead and bismuth radiopharmaceuticals
Jaclyn L Lange, Patrick RWJ Davey, Michelle T Ma, Jonathan M White, Alfred Morgenstern, Frank Bruchertseifer, Philip J Blower, Brett M Paterson
Dalton Transactions | ROYAL SOC CHEMISTRY | Published : 2020
A variant of 1,4,7,10-tetraazacyclododecane (cyclen) bearing two semicarbazone pendant groups has been prepared. The octadentate ligand forms complexes with Bi3+ and Pb2+. X-ray crystallography showed that the neutral ligand provides an eight-coordinate environment for both metal ions and intermolecular hydrogen bond interactions have influenced the coordination environments of both complexes in the solid state. NMR spectroscopy revealed a fluxional environment for both complexes. The ligand was radiolabeled with the α-emitting radioactive isotope 213Bi3+, which is used in systemic targeted radiotherapy. The resulting complex was stable in serum for at least 90 min (two decay half-lives). Th..View full abstract
Awarded by Australian Research Council
Awarded by Cancer Research UK Career Establishment Award
Awarded by EPSRC
B. M. P. acknowledges the Australian Research Council (DE170100540), the State Government of Victoria (Victorian Postdoctoral Research Fellowship) and the facilities and scientific and technical assistance of the National Imaging Facility, a National Collaborative Research Infrastructure Strategy (NCRIS) capability, at Monash Biomedical Imaging, Monash University. M. T. M. is supported by a Cancer Research UK Career Establishment Award (C63178/A24959). M. T. M. and P. J. B. are supported by the EPSRC programme for next generation molecular imaging and therapy with radionuclides (EP/S019901/1). We thank Dr Peter Nichols for his assistance with NMR experiments. We also thank Profs. Paul S. Donnelly (The University of Melbourne), S. R. Batten and K. S. Murray (Monash University) for the use of their laboratory facilities.