A new neutral bidentate schiff base mixed ligand metal ions complexes of the composition, [ML 1 L] (NO 3) 2 where M=Co(II), Ni(II), Cu(II), Zn(II) and Cd (II) L 1 =(4-nitro benzylidene)-urea amine, L=L a ,L b ligands derived from thiosemicarbazone and 4-chlorobenzaldehyde or 4bromobenzaldehyde were synthesis and characterized by elemental analysis, magnetic susceptibility, molar conductivity, FT-IR, UV-Vis, and 1 HNMR spectral studies .The conductivity measurements of cobalt(II), nickel (II),and copper (II) complexes were suggested to have a tetrahedral geometry, but Zn(II) and Cd (II) complexes were suggested to has square planner. The structural geometries of compounds were also suggested in gas phase by theoretical treatments, using Hyper chem-6 program for the molecular mechanics and semi-empirical calculations, an addition heat of formation (∆H f •) and binding energy (∆E b) for the free ligands and it's metal complexes were calculated by using PM3 method .PM3 was used to evaluate the vibration spectra of Schiff bases and compare the theoretically calculated wave numbers with experimental values ,the theoretically obtained frequencies agreed calculation helped to assign unambiguously the most diagnostic bands. The antimicrobial activities of the metal chelats against the bacteria, Escherichia coli and Staphylococcus aureus were studied.

Mannich bases derivatives of Benzimidazole were prepared from condensation reaction of 2mercaptobenzimidazole with formaldeyhed once with mropholine and another with pyrazinamide to prepare L 1 and L 2 respectively, coordinated with three metal ions of Pd(II), Pt(IV) and Au(III). The structures of these compounds were confirmed by metal and elemental analyses, UV-Vis and FT-IR spectroscopy, magnetic susceptibility, conductivity measurement at room temperature, 1 HNMR and 13 CNMR. Experimental results showed that the ligands (L 1 &L 2 ) coordinated as bi-dentate and tridentate with metal ions respectively. Cytotoxicity of Mannich bases and their metal complexes were examined against mice cell line RAW 264.7 using MTT method .Each cell line was injected by following doses (400,200,100 and 50) µg/ml of prepared compounds by using mice cell as a negative control and cis-platin as a positive control. The ligands and Pd(II), Pt(IV), Au(III) complexes showed good activity at various concentrations especially Pd(II) complexes of both complexes.

Biological activities of Cu (II), Pt (IV), Zn (II) and V (IV) metal complexes with 1, 3, 4 -thiadiazole derivatives towards pathogenic bacteria (Staph. aureus, Bacillus cereus, Pseudomonas aerogenosa and Escherichia coli) and the fungus Candida albicans were studied. The investigation was conducted using plate agar method. Sulfadiazine was used as standard drug in this study. The results were referred to that the biological activities of the studied compounds are more effective than sulfadiazine. The minimum effective dose of the studied compounds against of the named bacteria was 50µg/ml, while the minimum effective dose of sulfadiazine was 100µg/ml. Moreover, Candida albicans was affected by all the studied compounds at 50µg/ml, but there is no significant effect of sulfadiazine toward Candida albicans even at the highest dose, 200µg/ml.

New metal ions complexes of tridentate ligand (1-((dicyclohexylamino) methyl)-3-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrzol-4-ylimino) indolin-2-one) have been synthesized and characterized by chemical-physical analysis. The ligand acts as a tridentate for the complexation reaction with all metal ions. The new complexes, possessing the general formula [M(L)Cl]Cl where M=[Ni(II), Cu(II), Zn(II), Pd(II), Cd(II), Pt(IV) and Hg(II) ] ,show tetrahedral geometry. All complexes ,except Pd(II) complex which has a square planar geometry and Pt(IV) which show an octahedral geometry. The geometry of the prepared compounds has been proposed in another method theoretically by using one of the calculation molecular programs (Hyper chem.-6) program. Besides the comparison between the experimental results with the theoretical ones, show that the experimental results are so close to the theoretical counterpart.