Synthesis, Crystal Structure And Bioactivity Research Of Three Series Of Complexes With Antibacterial Activity

Three series of complexes that 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 two unprecedented one-dimension chain metal-organic coordination polymers Zn(H-SSA)(Phen)(H2O)2 andCu(H-SSA)(Phen)(H2O)2.The X-ray diffraction analysis reveals that the two compounds are isostructure. The 5-sulfosalicylic acid ligand has lost two protons at the sulfo-group and carboxylic group. The Zn(II) and Cu(II) ions are six-coordinated,and distorted octahedral geometry,which are surrounded by two N atoms from Phen,two oxygen from two water molecules,one oxygen from -SOa group and one oxygen from carboxylic group of the other H-SSA. The two compounds are unprecedented one-dimensional linear chain formed by a repeating mononuclear structural unit which is bridged by H-SSA. The fluorescent intensity of two compounds is much stronger than that of SSA at the maximum emission wavelength 400nm,which may be assigned to 7i-7i electron transfer of ligands. The antibacterial activity test shows that the two compounds strongly inhibit the growth of Streptococcus haemolyticus,Straphyloccus aureus and Escherichia coli,but their solubility is little in water.The second series of complexes is the ternary complexes of rare earth(Eu(III) and Nd(III)) with 2,4-dichlorophenoxy acetic acid(2,4-D) and l,10-phenanthroine(phen). The X-ray diffraction analysis reveals that the complex of Eu(lII) is binuclear molecules with space group P2(1)/n. The crystalloids belongs to monoclinic. The stucture of [Eu(2,4-D)2(phen)2J2-2(ClO4) is centrosymmetric dimmer in which each Eu(III) atom is 9 coordinated by four nitrogen atoms from two phen ,five oxygen atoms from four carboxylic groups. The carboxylic groups in the complex bond to the metal ion in the two coordinated modes ,the bridged bidentate and bridged tridentate modes. The stucture of [Nd(C8H5O3Cl2)3(C2H5O)]2 is centrosymmetric dimmer in which each Nd(III)atom is 7 coordinated by six oxygen atoms from five carboxylic groups,one oxygen from ethanol. The antibacterial activity test shows that the two compounds strongly inhibit the growth of two kind of fungus .The third serie of complexes is the ternary complexes of transition metal(Cu(II) andNi(II))with tridentate Schiff base of amino acid(Gly) and Imidazole(Im). The schiff base(N-salicylidene-glycine) is obtained from the reaction salicylidene and glycine. X-ray crystal stucture analysis revealed the complex [Cu(Sal-Gly)(Im)](1) is a ternary complex . The metal atom Cu(II) has a square-planar coordination with O,N,O atoms of the tridentate Schiff base dianion ,one N atom of the imidazole and the weakly coordinating carboxylic O3 atom of an adjacent complex molecule is located on the apical site.In this way,the Cu(II)complexes are bridged to dimers. The complex molecule is characterized by an axially elongated square-pyramidal. The complex is mononuclear molecules with space group P2(1)/c.The crystalloids belongs to monoclinic. The space group of complex Ni(Sal-Gly)(H2O)2 is P2(1)/c. The crystalloids belongs to monoclinic. The center metal Ni(II) is six-coordinated . The antibacterial activity test shows that the two compounds inhibit the growth of two kind of fungus,but effect is not very good ,their solubility is little in water too.The antibacterial activity test to the above-mentioned complexes shows that the antibacterial activity improved generally after the metal ion coordinated with ligands which are worth further researching and spreading have fungistatic ability .Meanwhile we also obtained the crystal of La(C12H8N2)2(CH3COO)2(H2O)2,X-ray crystal stucture analysis revealed that it is mononuclear molecule with space group PI. The crystalloids belone to triclinic. The cell parameters are a=11.250(4)A,b=13.364(4)A,c=16.327(5)A,a=l03.042(6) ,(3=90.327(6),y=99.567(6) ,Z=2,Dc=1.603 mg/m3,V=2355.8(12)A3...