2-氨基苯并噻唑和苯氧乙酸衍生物的铜配合物:配位模式和抗菌性能

摘要

以苯氧乙酸(Hpa)、对硝基苯氧乙酸(Hpnpa)和对甲基苯氧乙酸(Hpmpa)为原料,分别与2-氨基苯并噻唑(aben)和乙酸铜反应,合成了3种铜配合物[Cu(pa)2(aben)2] (1),[Cu2(pnpa)4(aben)2] (2)和[Cu(pmpa)2(aben)2]· [Cu2(pmpa)4(aben)2] (3),并通过元素分析、红外光谱和单晶X-射线衍射对其结构进行了表征.结果表明,3种配合物具有不同的配位模式,配合物1的中心Cu(Ⅱ)分别与2个羧基氧原子和2个噻唑环上的氮原子配位;配合物2的2个Cu(Ⅱ)则分别都与来自4个不同配体的羧基氧原子和1个噻唑环上的氮原子配位,从而在分子中形成了2个近乎垂直的八元环;配合物3为混配型化合物,1个Cu(Ⅱ)的配位数为4,另外2个Cu(Ⅱ)的配位数为5,参与配位的配体原子分别与配合物1和2相同.最低抑菌浓度的测定结果表明,3种配合物对真菌都表现出良好的抑制作用,且由于苯氧乙酸配体中取代基种类的不同,而使得配合物的抗菌效果出现明显的不同.%Three ternary complexes,namely [Cu(pa)2(aben)2] (1,pa=phenoxyacetic acid anion,aben=2-amino benzothiazole),[Cu2(pnpa)4(aben)2] (2,pnpa=p-nitrylphenoxyacetic acid anion) and [Cu(pmpa)2(aben)2]·[Cu2(pmpa)4(aben)2] (3,pmpa=p-methylphenoxyacetic acid anion),were synthesized by the reaction of copper acetate,2-amino benzothiazole and corresponding phenoxyacetic acid derivatives.Elemental analysis,IR spectra and X-ray single-crystal diffraction were used to determine the compositions and crystal structures.Studies reveal that the copper(Ⅱ) ion in complex 1 is four-coordinated with two carboxyl oxygen atoms of the two pa ligands and two nitrogen atoms from thiazole rings of the two aben ligands.In binuclear complex 2,each central copper(Ⅱ) ion is five-coordinated with four carboxyl oxygen atoms from four pnpa ligands and one nitrogen atom from thiazole ring of one aben ligand,but the two carboxyl oxygen atoms of every pnpa ligand take part in the coordination with different copper(Ⅱ) ions,which result in the formation of two eight-numbered rings in a unit cell.In trinuclear complex 3,there are four-coordinated and five-coordinated copper(Ⅱ) ions as described in the complex 1 and 2.Structure analysis shows that there are intermolecular and intramolecular hydrogen bondings between aminonitrogen atoms and carboxyl oxygen atoms (or even ether oxygen atoms in complex 3).Results of antimicrobial tests show that three copper complexes exhibit significant antifungal activities (MIC 1～10 μg ·mL-1) that are better than that of their original free ligands,and there are some differences in their antifungal properties,which are caused by the orienting substituted groups in the phenoxyacetic acid ligands.CCDC:831015,1; 831017,2;831016,3.