Synthesis, Characterization, Bioactivity Research Of Several Kinds Of Complexes With Antibacterial Activity

Three series of complexes which have antibacterial activity have been synthesized and characterized by elemental analysis, IR, UV, fluorescent spectra and single crystal X-ray diffraction analysis.The first series of complexes is three unprecedented compounds Zn(C7H6N2S)2(CH3COO)2(1), Ag(C7H6N2S)(NO3)(2), Cu-(Sal-Gly)-(C7H6N2S) (3). In compound 1,the Zn tom is four-coordinated by one N atom from each of two 2-aminobenzothiazole ligands and one O atom from each of two monodentate acetate anions, this ZnO2N2 coordination forms a distorted tetrahedral geometry with a local non-crystallographic C2 symmetry . The amino groups act as donors in N－H…O hydrogen bonds, two intermolecular N－H…O hydrogen bonds interconnect the molecules into a three-dimensional network. Compound 2 belongs to monoclinic crystal system. The X-ray diffraction analysis reveals that the compound is mononuclear with space group P2(1)/c, the Ag ion is two-coordinated with one O atom from NO3- and N atom from 1,3-thiazole ligand. Complex 3 is the ternary complexes of transition metal Cu with tridentate Schiff base derived from amino acid(Gly) and 2-aminobenzothiazole. The schiff base(Sal-Gly) is obtained from the reaction salicylidene and glycine. X-ray crystal stucture analysis revealed the complex 3 is a mononuclear molecule with space group Pbca. The crystal belongs to orthorhombic crystal system. The center metal Cu(II) is four-coordinated with O,N,O atoms of the tridentate Schiff base dianion, and one N atom of thethiazole . The complex 4 molecule is characterized by an axially elongated square-pyramidal. The space group of complex is P2(1)/c, the crystal belongs to monoclinic crystal system. The cell parameters are a=12.955(2), b=5.5463(10), c=11.423(2)?, β=106.288(4)°, Z=2, Dc=1.643 mg/m3, V=787.8(2)?3. The center metal Zn(II) issix-coordinated with distored octahedral geometry. Two H2O moleculars also coordinate with the metal Zn(II), strong hydrogen bonds are found in each unit between two fragments. The fluorescent properties of complex were investigated, which show that compound has stronger fluorescence than 8-hydroxyquinoline.The three series of complexes is the ternary complexes of rare earth (Nd(Ⅲ) and Sm(Ⅲ)) with 3,5-dinitrobenzonic acid and 1,10-phenanthroine(phen). Crystal structures of Complex 5,6 have been determined by single crystal X-ray diffraction. Nd(Phen)2(NO3)3(Mr =690.68) belongs to monoclinic crystal system, space group is Cc with crystal cell parameters: a=11.975(17), b=18.073(3), c=13.095(2)?, β=100.584(3)°, V= 2.6051(7)nm3, Z= 4 . The Nd(III) ion is coordinated in a distorted bicapped square-antiprism geometry and surrounded by four nitrogen atoms from two phen ligands and six oxygen atoms from three NO3- anions, respectively. Complex of Sm (Ⅲ) is binuclear molecules with space group P-1. The crystal belongs to triclinic crystal system. The stucture of complex is centrosymmetric dimmer in which each Sm(Ⅲ) atom is night-coordinated with distorted tricapped trigonal-prism(TTP) geometry by two nitrogen atoms from phen , seven oxygen atoms from carboxylic groups. The carboxylic groups in the complex 6 bond to the metal ion in the two coordinated modes, the bridged bidentate and bridged tridentate modes.