Vibrational Spectra of Three Maltolato Complexes with Interesting Pharmacological Properties

BARAN, ENRIQUE JOSÉ; PARAJÓN-COSTA, B.S.

Punta del Este

Congreso; XII. International Symposium on Metal Ions in Biology and Medicine; 2013

UDELAR y otros/Uruguay

VIBRATIONAL SPECTRA OF THREE MALTOLATO COMPLEXES WITH INTERESTING PHARMACOLOGICAL PROPERTIES   Enrique J. Baran & Beatriz S. Parajón-Costa   Centro de Química Inorgánica (CEQUINOR, CONICET/UNLP), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C. Correo 962, 1900-La Plata, Argentina. (E-mail: baran@quimica.unlp.edu.ar)        Maltol, 3-hydroxy-3-methyl-4-pyrone is one of several hydroxypyrones long known for high bioavailability and favourable toxicity profiles. It has a high affinity for different metal cations and is, therefore, an excellent choice for the formulation of therapeutic and/or diagnostic metallopharmaceuticals 1.      We have prepared three metallic complexes of this ligand, namely with VO2+, Zn(II), and Ga(III) respectively. The first two show insulino mimetic activity 1-3 and the other one is a very promising antitumoral drug 4.      The FTIR and Raman spectra of polycrystalline samples of the three complexes were recorded and briefly discussed on the basis of their crystal structures and by comparison with the spectroscopic behavior of free maltol and of other, previously investigated, maltolato complexes. ___________________________     1 Thompson, K.H.; Barta, Ch.A.; Orvig, Ch. Metal complexes of maltol and       close analogues in medicinal inorganic chemistry. Chem Soc Rev; 2006;       35; 545-556.    2  Thompson, K.H.; Orvig, Ch. Vanadium: in diabetes: 100 years from phase        to phase I. J Inorg Biochem; 2006; 100; 1925-1935.    3  Yoshikawa, Y., Ueda, E., Kawabe, K., Miyake, H., Sakurai, H., Kojima, Y.        New insulin-mimetic zinc(II) complexes; bis-maltolato zinc(II) and bis-2-        hydroxypyridine-N-oxido zinc(II) with Zn(O4) coordination mode. Chem Lett;        2000; 874-875.    4  Jakupec, M.A., Keppler, B.K. Gallium in cancer treatment. Curr Top Med        Chem; 2004; 4; 1575-1583.