Kinetic Inertness and Electrochemical Behavior of Copper(II) Tetraazamacrocyclic Complexes: Possible Implications for in Vivo Stability

• Published in: European Journal of Inorganic Chemistry Vol. 2005; no. 23; pp. 4829 - 4833
• Main Authors: Woodin, Katrina S., Heroux, Katie J., Boswell, C. Andrew, Wong, Edward H., Weisman, Gary R., Niu, Weijun, Tomellini, Sterling A., Anderson, Carolyn J., Zakharov, Lev N., Rheingold, Arnold L.
• Format: Book Review Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01.12.2005; WILEY‐VCH Verlag; Wiley
• Subjects: Chemistry; Chemistry, Inorganic & Nuclear; Copper; Macrocyclic ligands; N ligands; Physical Sciences; Science & Technology; copper; N ligands; macrocyclic ligands; DISSOCIATION; METAL-COMPLEXES
• ISSN: 1434-1948; 1099-0682
• DOI: 10.1002/ejic.200500579

The kinetic inertness of copper(II) complexes of several carboxymethyl‐armed cyclams and cyclens in 5 M HCl have been determined confirming that the complex derived from cross‐bridged cyclam (Cu‐CB‐TE2A) is by far the most resistant to acid decomplexation. FT‐IR studies in D2O solution revealed its unique resistance to full carboxylate protonation and its retention of coordination by both pendant arms even in 1 M DCl. The X‐ray structure of its monoprotonated form, [Cu‐CB‐TE2AH]+, also established full coordination by both COO– and COOH pendant arms in the solid state. Cyclic voltammograms of four carboxymethyl pendant‐armed cyclam and cyclen complexes in aqueous solution were obtained with only Cu‐CB‐TE2A displaying a quasi‐reversible CuII/CuI reduction wave. These indicators correlate with the superior in vivo behavior of this complex and its bifunctional conjugate. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)