Synthesis and Biological Study of Some Transition Metal Ions Complexes of Schiff-Mannich Base Derived from 2-Amino-5- Mercpto-1,3,4 Thiadiazole

The Schiff-Mannich base was derived from 1,3,4 thiadazole prepared by combining of 2-amino-5-mercapto-1,3,4 thiadazole and 4-N,N-dimethyl benzaldehyde with indol. The result compound was 5-((1 H-ind ol -1-yl) methylthio)-N-(4-(dimethylamino)benzylidene)-,1,3,4-thiadiazol-2-amine(L), coordinated with six metal ion Co(II), Ni(II), Cu(II), Pd(II), Pt(IV), and Au(III). The ligand (L) has been characterized by using the following techniques, C.H.N.S, FT-IR, UV-ViS, 1H-NMR, and 13C-NMR. In addition, the measurement of (atomic absorption spectra, magentic susceptibility, and molar conductivity) was used when diagnosing the complexes. The experimental results showed that the ligands coordinated as tri-dentate with metal ions. The antibacterial and antifungal activity of all complexes were studied against Staphylococcus aureus and Bacillus subtilis as a model of gram-positive, as well as E-coli and Klebsiella pneumoniae as a gram-negative at a concentration of 0.02 M. Likewise, the effectiveness of the prepared compounds was determined in inhibiting selected types of bacteria and fungi. The results showed that the prepared metal complexes and ligand are more effective than the standard drug in bacteria and fungi. The metal to ligands ratio was determined by the molar ratio method and showed the metal interaction with the ligand proportion (1:1). Also, the compounds prepared were studied in gas phase by using the hyper-chem8.0.7 program. Through this program, the heat of formation, binding energy, HOMO and LUMO, and the electrostatic potential in addition to the infrared vibration of the ligand were calculated.