THE INTERACTION BETWEEN SULFATHIAZOLE AND COBALT(II): POTENTIOMETRIC STUDIES

SEBASTIÁN BELLÚ; MARCELA RIZZOTTO; NORA OKULIK; ALICIA JUBERT

QUíMICA NOVA

Año: 2007 vol. 30 p. 1136 - 1142

0100-4042

Potentiometric studies of sulfathiazole (HST) in the presence and absence of cobalt(II) were performed. Equilibrium constants forthe formation of the detected species, [Co(ST)]+ and [Co(ST)(OH)], are reported. UV-Vis spectrophotometric measurements suggestthat the coordination Co(II)-sulfathiazole might be through a N atom, which, in agreement with MO calculations, could be a thiazolicone. In spite of sulfonamides being better ligands at pH >7, [Co(ST)]+ was found at pH ≈ 3.