Synthesis, Characterization and Antimicrobial Studies of Transition Metal Complexes of Schiff
Base derived from Salicylaldehyde and L-Tyrosine Amino Acid

Eugene-Osoikhia, T. T*., Akinpelu, I. O and Odiaka, T. I.
Department of Chemistry, University of Ibadan, Ibadan, Nigeria

*Corresponding Author: kemitunmise@yahoo.co.uk;Tel: +2348030487007

Abstract

Tridentate Schiff base Salicylidene-tyrosine (H2L) of biological importance obtained from
salicyaldehyde and L-tyrosine and their Mn(II), Fe(II), Co.(II), Cu(II) and Ni(II)
complexes have been synthesised in 1:1 stochiometric ratio and characterised on the basis
of their solubility, metal analysis, infrared, UV-Visible and magnetic measurements. The
synthesised complexes have different shades of colour and decomposed at a temperature
above 360oC. Salicylidene-tyrosine behaved as a tridentate ligand coordinating to the
metals through the azomethine nitrogen atom, the oxygen atom of hydroxyl group of
COOH and the phenolic oxygen to give an octahedral geometry. The electronic spectra
were consistent with the proposed octahedral geometry around the metal ions. The metal
complexes were screened for their antimicrobial activities against Staphylococcus aureus
(ATCC 12600), Escherichia.coli (ATCC 8739), Pseudomonas aeruginosa (ATCC 10145),
Bacillus subtilis (ATCC 39090), Salmonella typhi (ATCC 6539), Klebsiella pneumonia
(ATCC 35657), Candida albicans (ATCC 10231), Penicillium notatum (ATCC 20269),
Rhizopus stolonifer (ATCC 14037) and Aspergillus niger (ATCC 16888). The copper
complex [Cu(L)(H2O)3].H2O exhibited the highest activity in all the organisms tested It is
active against all microorganisms tested at virtually all concentration