Metal ion complexes of Sr(ll), Cd(ll), Pb(ll), Zn(ll) with substituted pyrazoles, isoxazoles and their antimicrobial activities

The stability constant of some metal ions like Sr(II), Cd(II), Pb(II) and Zn(II) complexes with substituted 1-Carboxamido-3-(2-hydroxy-5-methylphenyl)-5-phenylpyrazole (ligand 1) and 3-(2-hydroxy-5-methylphenyl)-5-phenylisoxazole (ligand 2) have been investigated by pH metric technic at 1 x 10-3 M ionic strength and at 30 ± 0.10 C in 70% alcohol (methanol) water mixture. The Data obtained were used to compare and evaluate the values of proton-ligand stability constant (pK) and metal-ligand stability constant(log k), proton-ligand and metal-ligand stability constant have been determined by Bjerrum method, it is observed that Sr(II), Cd(II), Pb(II) and Zn(II) metal ions forms 1:1 and 1:2 complexes with both ligands. The ligands and their corresponding complexes were also screened for their antimicrobial activities.