N-Salicylideneamino acidato Complexes of Divalent Transition Metal Ions from the Cysteine

The divalent transition metal ions [Mn, Co, Ni, Cu and Cd] complexes with Schiff base derived from the reaction of Salicylaldehyde with D, L-Cysteine have been prepared and investigated by using different techniques; such as; elemental analysis, molar conductance measurements, infrared electronic and mass spectra. The elemental analysis data exhibit the formation of 1:1 [M: L] ratio. The molar conductances of the solid complexes indicate that they are of non-electrolytic nature. The infrared spectral data exhibit the coordination sites of the free Schiff base towards the metal ions under investigation. The electronic spectral data of the Schiff base and its complexes display the existence of d-d*, n-d* (C = N) transitions and an octahedral structure for all prepared complexes. The mass spectral data reveal the possible fragmentations in the Schiff base. The free ligand (Schiff base) and their complexes have been tested for their antibacterial activities against several human pathogenic bacteria (some of which were resistant to commercially used antibacterial). The results showed a great activity of Co(Il) complex against Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa. In contrast, no activities were recorded against Staphylococcus aureus. However; Cu(II) complex showed a great effect against Escherichia coli and Pseudomonas aeruginosa. No effect of other compounds tested observed against all bacteria used.