Preparation of tetrazine-containing [2 + 1] complexes of 99m Tc and in vivo targeting using bioorthogonal inverse electron demand Diels–Alder chemistry

The aim of this work was to synthesize and evaluate [2 + 1] ^99mTc(i) polypyridine complexes containing tetrazines, which along with the corresponding Re(i) complexes, represent a new class of isostructural nuclear and turn-on luminescent probes that can be derivatized and targeted using bioorthogonal chemistry. To this end, [2 + 1] complexes of ^99mTc(i) of the type [^99mTc(CO)₃(N^N)(L)] (N^N = bathophenanthroline disulfonate (BPS) or …