Copper(II) cyclam-based complexes for radiopharmaceutical applications: Synthesis and structural analysis

Abstract

Two molecular structures of the copper(ii) complex, Cu(H 2 TETA), have been determined by X-ray crystallography. The Jahn-Teller distortion differs between the two structures; occurring either along the axis of the pendant acetate arms or across the macrocyclic ring. An analysis of deposited data from over one hundred copper(ii) cyclam X-ray structures in the Cambridge Structural Database (CSD) reveals that Jahn-Teller distortion across the ring is highly unusual for such compounds in the solid state. Novel chelators based on the piperazino/side-bridged cyclam have been prepared and copper(ii) complexes formed. The single crystal X-ray structures of two copper(ii) complexes, with either an ester or acid N-pendant arm, have been determined and in both cases the pendant arm is bound to the metal centre. © The Royal Society of Chemistry.