Stability constant of some Anti-Tuberculosis metal drug complexes

Abstract

The formation of Isonicotinic Acid Hydrazide and Pyrazine-2-carboxamide complexes were prepared and analyzed by determining the stoichiometry and stability constant (Spectrophotometric method).  The ionic strength used was maintained constant at 0.1 M KNO₃. The stability constants were calculated to be log 61.21 - 254 in Isonicotinic Acid Hydrazide while in Pyrazine-2-carboxamide 55.5 - 274.29.  The order of stability constant of the metal to ligand reaction follows this trend: Ni(II) > Cu(II) > Co(II) > Fe(II) > Mn(II) > Zn(II). The order of the stability constant is in agreement with the trend of Electronegativity.