Mild and efficient 64Cu labeling of perhydro-1, 4-diazepine derivatives for potential use with large peptides, proteins and antibodies

Abstract DATA (6-Amino-1,4-diazapine-triacetate) and AAZTA (6-Amino-1,4-diazapine-tetracetate) chelators represent a novel approach representing hybrid-chelates: possessing significant cyclic and acyclic character. It is believed that flexibility of the acyclic part facilitates rapid complexation, whilst the preorganized cyclic part minimizes the energy barrier to complexation and inhibits decomplexation processes. So far, these chelators have been used exclusively with 44Sc and 68Ga only. Recent results with natCu predict high stabilities for Cu-AAZTA, yet no radioactive labeling of AAZTA or DATA with 64Cu or any additional radioactive isotope has been reported. We present the one pot synt…

Synthesis and labeling of a squaric acid containing PSMA-inhibitor coupled to AAZTA5 for versatile labeling with 44Sc, 64Cu, 68Ga and 177Lu