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

Eurobic9, 2-6 September, 2008, Wrocław, Poland
P185. Coordination Ability of Hydroxamic Acid Analogues Towards
Biometal Ions
M. Sowińska a , J. Gałęzowska a , I. Fritsky b , J. Świątek-Kozłowska a
a
Department of Inorganic Chemistry, Wrocław Medical University, Szewska 38, 50139, Wrocław, Poland,
malgorzata.sowinska@chnorg.am.wroc.pl
b
Department of Chemistry, National Taras Shevchenko University, , 01033, Kiev, Ukraine
The trials with metal chelators for neurodegenerative diseases treatment prompted renewed interest in assessing
whether their therapeutic action is related to the coordination of neurotoxic trace metals, such as Cu(II), Fe(III)
and Zn(II).
Neurodegenerative disorders are characterized by the evidence implicating the central role of these metals.
Numerous studies have established the roles of redox-active transition metals in the pathogenesis of
neurodegenerative diseases [1, 2]. Iron, copper, zinc and other metals are usually found in essential normal
biological processes and are also involved in enzymatic activities. However, in appropriate accumulation of
excessive metal deposits can also be cytotoxic. Evidences of alteration in metal ions metabolism have been
reported in various diseases like Alzheimer's, Wilson, Menkes, Prion, Pick, Huntington disease, epilepsy and
other pathological events. Thus, metal ions play a important role in neurodegenerative phenomena.
Hydroxamic acids are very effective chelators for different metal ions [3-7]. Basically, trivalent metal ions i.g.
Fe(III) or Al(III) complexation by hydroxymates takes place via the two oxygens of the hydroxamic group
through the formation of a stable 5-membered chelate ring [3].
Cyclic voltammetry offers a convenient route for the determination of ligand protonation/deprotonation
constants and also for metal-ligand complex stability constants in aqueous media. The obtained results allow us
to calculate the stability constants of the studied ligands towards the: Cu(II), Ni(II), Fe(III) and Zn(II) metal ions.
Conditional stability constants (Kc) are the key for quantifying and therefore understanding reactions that may
be relevant to biology and therapeutics of drugs. Spectroscopic and electrochemical methods were used in the
present studies.
References:
[1]. A.I.Bush, Neurobiol Aging, 23, 1031 (2002)
[2]. E.Ferrada, V.Arancibia, NeuroToxicology, 28, 445 (2007)
[3]. E.Gumienna-Kontecka, J. Chem. Soc. Dalton Trans., 4201 (2000)
[4]. E.Farkas, E.A.Enyedy, J. Inorg. Biochem., 79, 205 (2000)
[5]. H.Kurzak, H.Kozłowski, Coord. Chem. Rev., 114, 169 (1992)
[6]. A.Dobosz, N.M.Dudarenko, J. Chem. Soc. Dalton Trans., 743 (1999)
[7]. T.W. Failes, T.W.Hambley, J. Inorg. Biochem., 101, 396 (2007)
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