SPECTROSCOPIC STUDIES OF METHIMAZOLE REACTIVITY IN
AQUEOUS SOLUTIONS
D. Cvijanović*, V. Damjanović, J. Lovrić, I. Picek, B. Foretić
Department of Chemistry and Biochemistry, School of Medicine, University of Zagreb, Zagreb, Croatia
*danijela.cvijanovic@mef.hr
The reactions and coordination ability of S, N-containing heterocyclic ligands such
as methimazole (MMI=2-mercapto-1-methylimidazole, Fig. 1) have been of
considerable interest both from structural point of view and pharmacological importance
of MMI (1, 2). This study has been undertaken to investigate the mode of coordination
of MMI to the pentacyanoferrate(II) moiety, [Fe(CN)5]3-, known as a selective probe for
binding one specific group of ambidentate ligands to iron(II).
Figure 1. The tautomers of methiamazole.
Predominance of reactive tautomeric MMI isomer in aqueous solutions (pH 2-11)
is determined and the stability of the formed complexes is discussed and correlated with
the iron-ligand bond type and the electronic properties of the ligand. The experimental
data were obtained by means of NMR and UV/Vis spectroscopy.
1. H. T. Flakus, A. Miros, P. G. Jones, Spectrochim. Acta Part A 58 225 (2002).
2. L. B. Kumbhare, U. Singh, B. G. Singh, A. Wadawale, G. Kedarnath, S. S. Zade, K. I.
Priyadarsini, V. K. Jain, Inorg. Chim. Acta (2011) in press.