Synthesis, Structural Synthesis, Structural Synthesis, Structural Synthesis, Structural Biological Studies Biological StudiesBiological Studies Biological Studies and and and and theoretical treatment of new chelating ligand with theoretical treatment

A new ligand have been prepared in this work, which was chosen to synthesis a new set of transition metal complexes [Mn(ІІ),Co (II), Ni (II),Cu(ІІ),Zn(ІІ),Hg (II),Cd (II),Pd(ІІ), Cr(ІІІ) and Rh (IІI)]. The new ligand (Potassium (Benzothiozole-2-dithiocarbamato hydrzide)) was isolated and characterized by appropriate physical measurements, vibrational and uv- vis spectroscopy.This dithiocarbamate derivative (L) has been used as ligand to prepare a number of new complexes with the selected metal ions, [Cr(ІІІ),Mn(ІІ),Co (II), Ni (II),Cu(ІІ),Zn(ІІ),Hg (II),Cd (II),Pd(ІІ) and Rh (IІI)].These complexes were studied and aracterized using FT.IR, UV-Vis Spectroscopy, molar conductivity, magnetic susceptibility melting points and atomic absorption measurements. It concluded that {[CrL].3EtOH,{[CuL2(H2O)2].H2O and [NiL2(H2O)].4EtOH} have octahedral geometries ,{[RhL22]Cl  and [PdLCl].1.5EtOH} have square planergeometries and {[CoL(H2O)Cl].3EtOH, {[ZnL].6EtOH,[MnL2].1.5EtOH and [CdLNO3].3EtOH ,[HgL2].XHO} have atetrahedral geometry. Different bonding and structural behavior were revealed through the study of the coordination chemistry of the metal complexes of the new ligand.2The nature of bonding between the metal ion and the donar atoms of the ligand were demonstrated through the calculated of Racah parameter and the other ligand field parameters, which were calculated using the suitable Tanaba-Sugano diagrams.A theoretical treatment of the formation of complex in the gas phase was studied; this was done using the hyperchem-6 program for the Molecular mechanics and semi- empirical calculations. The heat of formation (∆H˚f) and binding energy (∆E) for the free ligand and its metal complexes were calculated by (PM3 and ZINDO/1) methods, at 298˚K. Furthermore, the electrostatic potential of the free ligand was calculated to investigate the reactive sites of the molecule. PM3 was used to evaluate the vibrational spectra of the free ligand (L), and these obtained frequencies agreed well with those values experimentally found,in addition, the calculation helped to assign unambiguously the most diagnostic bands.b The antibacterial activity for the starting material, the ligand and its metal complexes were studied against two selected microorganisms (Staphylococcus aureus) and (Pseudomonas aeruginosa), using (10 mM) and (5mM) concentration in nutrient agar medium.The results were showed a great enhancement of activity of some
complexes relative to that of their respective ligand. These were attributed to the synergetic effect between the metal ion and the ligand, in addition to the differences in the structural varieties.