The complexes of ML 2 were synthesized where M= Co(II), Ni(II) and Cu(II) and L= 2-Butyl thioquinazoline 4 (3H)-semicarbazone (BTQS). The ligand have been synthesized by condensation of thioquinazoline-4(3H)-one with semicarbazide hydrochlande characterized by molar mass, elemental analysis, Infrared spectra, electronic spectra, magnetic susceptibility and molar conductance measurements. The ligand BTQS acts as neutral bidentate chelating agent and coordinated to metal ions through azomethine nitrogen and carbonyl oxygen of semicarbazone moiety. The remaining Coordination centres are satisfied by anions such as Cl

Prevention of disease by the development of active treatments that control illness with minimum side effect to the human being has become the vital goal of modern health care. The use of antibiotics in medicine has resulted in an increasing number of resistant strains of microorganism, through mutation and gene transfer. Medical research has proved through extensive evidence that most of the diseases are mainly . On the basis of molar conductance data complexes are proposed non-electrolytic in nature. On the basis of physicochemical and spectroscopic studies, the structure of the Co(II), Ni(II) and Cu(II) complexes was proposed octahedral in nature. All the synthesized ligand and complexes have been screened for antimicrobial activity.

INTRODUCTIONSchiff bases have the ability to act as coordinating ligands and the polynuclear complexes derived from Schiff bases find variety of applications in analytical and biological systems [1][2][3][4][5][6][7][8][9][10][11][12] . Schiff base complexes of transition metals are of great interest and have extensively been studied over past few decades [13][14][15][16] ABSTRACTIn the present paper, a series of complex of the type [MLX 2 ] where M = Co(II), Ni(II) and Cu(II), L = 6-methyl-2-phenyl-4H-chromen 4-thisemicarbazone (MPCT) have been synthesized. Their structure were confirmed by means of IR, electronic spectra, elemental analysis and molar conductance, coupled with magnetic susceptibility measurements. All the compounds were assayed for antibacterial activities against one gram positive bacterial strain Bacillus subtilis and one gram negative bacterial strain Eschericpia coli, using disc diffusion technique. It was observed on comparison with reference to antibiotic and fungicides. The complexes were found to be more effective than ligands. Schiff base coordination compounds, the present work was undertaken to study the complexes of Co(II), Ni(II) and Cu(II) ions with bioactive ligands. In the present paper, we report a series of new Co(II), Ni(II) and Cu(II) complexes of Schiff base 6-methyl-2-phenyl-4H-chromen-4-thiosemicarbazone. The complexes have general molecular formula [MLX 2 ]; where M = Co(II), Ni(II) and Cu(II); L = 6-methyl-2-phenyl-4H-chromen-4-thiosemicarbazone (MPCT) and X = Cl -, Br -, I -and NO 3 -.

Coordination compounds play a vital role in several fields Schiff base plays a central role in the field of coordination chemistry due to their biocidal activities including anticancer, antifungal, herbicidal and antibacterial. The high reactivity specificity and a number of Schiff bases in industry, medicine & agriculture are used in catalytic reaction and as biological models for understanding biomolecules. Schiff base compounds that are ABSTRACT A series of complexes having the formulae [M(MTQS) z X z ], where M = Co(II), Ni(II) and Cu(II), MTQS = 2-methyl thioquinazoline -4 (3H) semicarbazone, X = Cl -, Br -, I or NO 3 the ligand as well as metal complexes have been characterized by elemental analysis, magnetic susceptibility, molar conductance, electronic spectra and infrared spectra. On the basis of these studies the complexes of Co(II) and Ni(II) are reported to be octahedral geometry whereas Cu(II) complexes are imposed to be distorted octahedral in geometry. The complexes exhibit enhanced antifungal activity as compared to parent ligand.

Metal complexes of Schiff bases have played a significant role in the area of coordination compounds. The ligational behaviour of Schiff base towards the central metal ions provide versatility and extra stability of compound making a greater choice of flexibility.The chelating ability of analytical and biocidal application of Schiff bases have attracted remarkable attention [1][2][3][4][5][6] . In continuation of these series of investigation [7][8][9][10][11][12][13][14][15][16] -. The geometry of the complexes have been elucidated in the light of molar mass, elemental analysis, IR, electronic Spectra, molar conductance and magnetic susceptibility. The measured molar conductance value indicates that the complexes are non-electrolytic in nature. The above observation indicates that Schiff bases EHPQH behave as bidentate ligand and coordination proposes through azomethine N and oxygen atom of alcoholic group of ligand. The remaining coordination sites are satisfied by negative ion such as Ci -, Br -, I -and NB -. The geometry of the Co(II) and Ni(II) were proposed to be octahedral in geometry whereas Cu(II) complexes were proposed to be distorted octahedral. The Schiff bases and its complexes have been evaluated for their antibacterial activity. The complexes show enhanced antibacterial activity than ligand.