Stability of Cu(II) and Zn(II) Complexes with Pyridinecarbohydrazones of Pyridoxal-5-phosphate in Aqueous Solution

Abstract

Composition of coordination compounds formed by copper(II) or zinc(II) ions and pyridine-2-, -3-, and -4-carbohydrazones of pyridoxal-5-phosphate in aqueous solution at 298.2 K, рН 7.4, I 0.25 has been studied by means of spectrophotometry. Conditional constants of the complexes stability have been determined. Cu(II) ions formed more stable ML₂ coordination compounds in comparison with Zn(II), zinc(II) ions are efficiently bound to the derivative of picolinic acid hydrazide to form the ML complex.