New azomethine Schiff base amino acid ligands derived from the condensation reaction of 3–
methoxysalicylaldehyde (MS) or 4-diethylaminosalicylaldehyde (DS) with some of α-amino acids (L-phenylalanine (Phe),
L-histidine (His), DL-tryptophan (Trp)) and their Fe(II) complexes were prepared. Structures of the synthesized Fe(II)
complexes were determined on the basis of elemental analysis, infrared, ultraviolet-visible spectra, thermal analysis and
cyclic voltammetry (CV) as well as conductivity, magnetic susceptibility measurements. Moreover, the particle size
distribution of the prepared complexes was determined by using transmittance electron microscope (TEM). The
experimental results show that the investigated Fe(II) complexes contain hydrated water molecules (expect DSPFe
complex) and coordinated water molecules (only in MSHFe complex), The kinetic and thermal parameters were determined
from the thermal data using Coast and Redfern method,. The results suggest that MS or DS amino acid Schiff bases behave
as monobasic tridentate ONO ligands and coordinate to Fe(II) in octahedral geometry according to the general formula
[Fe(HL)2].nH2O. But in the case of MSHFe complex, MSH ligand acts as tetradentate ((NH4
+
)[Fe(HL)(H2O)SO4]
-
.2H2O).The conductivity values between 43.30-5.66 Ω-1 mol-1
cm-2
in DMF suggest the presence of non-electrolyte species,
except MSHFe complex is electrolyte species (60.3 Ω-1 mol-1
cm-2
). Moreover, the antimicrobial evaluation of the prepared
Schiff base amino acid ligands and their Fe(II) complexes was examined against three types of bacteria such as B. subtilis
(+ve), E. coli (-ve) and M. luteus (+ve) and three types of fungi such as A. niger, C. glabrata and S. cerevisiae. The results
of these studies signalizing that the metal chelates exhibit a stronger antimicrobial efficiency than their corresponding
ligands. Moreover, the interaction of the prepared Fe(II) complexes with (CT-DNA) by using spectral studies, viscosity
measurements and agarose gel electrophoresis was investigated. Furthermore, antioxidant activities of the synthesized
complexes were examined by using the ABTS assay and showed that the prepared complexes have a good antioxidant
activity.