Bridging the Gap between in Vitro and in Vivo Imaging: Isostructural Re and 99mTc Complexes for Correlating Fluorescence and Radioimaging Studies

A bifunctional ligand that is capable of forming Re and 99mTc complexes as complementary fluorescent and radioactive probes was developed. The tridentate bis(quinoline) amine ligand, which is referred to as the SAACQ system, was prepared in a single step from Fmoc protected lysine in high yield. Reaction of the SAACQ ligand with [Re(CO)3Br3]2- resulted in the formation of the SAACQ-(Re(CO)3)+complex which exhibits favorable fluorescence …