ISBN: 978-83-60043-10-3 - eurobic9

Eurobic9, 2-6 September, 2008, Wrocław, Poland
O12. Comparative Structural, Spectral, and Acid Inertness Studies of
Copper(II) Adamanzane Coordination Compounds:
Effect of pH and Chloride Ions
K. Jensen a, b , P.W. Thulstrup a , I. Søtofte c , M. Jensen b and M.J. Bjerrum a
a Bioinorganic Chemistry, Department of Natural Sciences, Faculty of Life Sciences, University of Copenhagen.
Thorvaldsensvej 40, 1871 Fredriksberg C. Denmark. (krje@life.ku.dk)
b Hevesy Laboratory, Radiation Research Department, Risø DTU, National Laboratory for Sustainable Energy.
Technical University of Denmark. Frederiksborgvej 399, 4000 Roskilde. Denmark.
e-mail: Kristian.jensen@risoe.dtu.dk
c Department of Chemistry, Technical University of Denmark. Kemitorvet 207, 2800 Kgs. Lyngby. Denmark
An increased interest for the use of positron emission tomography (PET and PET/CT) scanners for “molecular”
imaging has become more common at the hospitals along with the medical cyclotrons. Various copper isotopes
have favorable decay properties for the use in both imaging and targeted radiotherapy.
With copper radioisotopes there is a need for novel chelators which can form kinetically and thermodynamically
stable coordination compounds, in order to avoid untimely dissociation of the radiolabelled compound. Thus, the
stability of the copper compounds is of considerable importance in ligand design aimed at in vivo delivery of
copper-radioisotopes.
Adamanzanes [1] are a class of bicyclic tetraaza ligands, which are well-suited for this type of application.
Adamanzane ligands were designed to form highly stable coordination compounds with Cu(II), among others
metals.
We have compared adamanzanes (A and B) and adamanzanes functionalized with carboxymethyl groups (C and
D). The latter should be able to engage in six-coordination of the metal-ion, and furthermore neutralize the
dicationic charge of Cu(II). We have applied cyclic voltammetry, UV-VIS and FT-IR spectroscopy in the study
of the stability, particularly with regards to reduction, chloride ion concentration and inertness towards acidic
decomposition in order to mimic in vivo conditions. Analyses are compared to solid state structures obtained via
x-ray crystallography.
A: [3 5 ]adz, B: [Cu([3 5 ]adz)Br] + C: (N’-CH2COOH)2[3 5 ]adz and D: [Cu((N’-CH2COO)2[3 5 ]adz)]
References:
[1]: Springborg J. Adamanzanes - Bi- and Tricyclic Tetraamines and Their Coordination Compounds. Dalton
Transactions 2003;(9):1653-1665.
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