Gallium Fluoride Complexes with Acyclic Bispicolinic Ligands as Potential New Fluorine-18 Labelled Imaging Agents

Abstract

The positron-emitting radionuclide, fluorine-18, is used to radiolabel molecules to develop tracers for diagnostic imaging with positron-emission tomography. There is growing interest in the potential of using strong coordinate bonds between electropositive Ga(III) and electronegative fluoride (≈ 557 kJ/mol) to provide new methods of incorporating fluorine-18 into molecules. The potential of gallium(III) complexes with acyclic pentadentate bispicolinic acid containing ligands (H2L1–3) to form ternary complexes with fluoride, [GaL1–3F] was investigated with a view to developing new methods for fluorine-18 radiolabelling. A solid-phase peptide synthesis approach was used to produce a bispicoli..