A new series of Mn(II), Fe(II), Co(II), Cu(II) and Zn(II) mixed ligands-metal
complexes derived from salicylic acid (SA) and 1,10-phenanthroline (PHEN) have been
synthesized and characterized by spectroscopic studies. The coordination of the two ligands
towards central metal ions has been proposed in the light of elemental analysis, IR, UV–vis
spectroscopic studies. The results of the physical and spectroscopic data confirmed that the
ligands are chelating agents. In 1, 10-phenanthroline, coordination occurred through the two
pyridinic nitrogen groups, while in the salicylic acid coordination occurred through the oxygen
of the hydroxyl and the carboxylic groups. All the complexes synthesized were of octahedral
geometry.Antimicrobial activity of the mixed ligands metal complexes and the free ligands were
carried out against the bacterial
Escherichia coli
,
staphylococcus aureus
,
klebsiella pneumonia
,
pseudomonas aeruginosa
and the fungi
candida
spp. The mixed ligands metal complexes
showed higher activities when compared to the free ligands of salicylic acid but were less active
than the free 1,10-phenanthroline ligand. The complexes of Cu (II) showed the highest
antimicrobial activity while the Fe(II ) complex showed the least activity against the bacterial
and fungi organisms.
