Syntheses, Crystal Structures, Antimicrobial Activity and Thermal Behavior of Copper(II) Complexes Derived from 1-Naphthylacetic Acid and Diamines.

Two copper(II) complexes, [CuL2(EA)] (1) and [Cu2L4(PA)2]·2H2O (2·2H2O), where L is 1-naphthylacetate, EA is N,N-diethylethane-1,2-diamine, PA is propane-1,3-diamine, have been prepared and characterized. Structures of the complexes have been characterized by single-cyrstal X-ray diffraction. Complex 1 is a mononuclear copper(II) compound, with the Cu atoms coordinated in square planar geometry. Complex 2·2H2O is a centrosymmetric dinuclear copper(II) compound, with the Cu atoms coordinated in square pyramidal geometry. Single crystals of the complexes are stabilized by hydrogen bonds. The effects of the compounds on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans, as well as thermal behavior of the complexes were studied.

Synthesis, crystal structure, and properties of a double-helical zinc(II) coordination polymer with Ozagrel drug.

By the reaction of Zn(OAc)(2)·2H(2)O with Ozagrel, (E)-3-(4-((1H-imidazol-1-yl)methyl)phenyl)acrylic acid (Himpaa), a novel coordination polymer [Zn(impaa)(2)](n)(1) was synthesized and was characterized by IR, elemental analysis, single-crystal X-ray diffraction analysis, photoluminescence spectroscopy, and thermogravimetric and differential thermal analysis. The four-coordinate Zn(II) ions are linked into 1D double-helical chain by the deprotonated impaa(-), which is extended into a 3D supramolecular structure through intermolecular C-H···O hydrogen bonds.

(Imidazole-κN){N-[1-(2-oxidophenyl)ethylidene]-l-valinato-κO,N,O'}copper(II).

In each of the two independent mol-ecules in the asymmetric unit of the title compound, [Cu(C(13)H(15)NO(3))(C(3)H(4)N(2))], the Cu(II) atom is four-coordinated by two O atoms and the N atom of the tridentate Schiff base ligand and one N atom from the imidazole ligand in a distorted square-planar geometry. In the crystal structure, mol-ecules are linked by inter-molecular N-H⋯O hydrogen bonds.

[The reaction mechanism of metolachlor and S-isomer with urease].

The binding of metolachlor and S-Isomer to urease in aqueous solution was studied using UV difference spectrum and fluorescence spectrum. According to the results of the UV difference spectrum curve, the UV difference adsorption deltaA changed rapidly when herbicide concentration increased from 0.0 to 1.6 micromol x L(-1) x UV difference spectra were red-shifted and absorb-peaks became lower. It was shown that herbicide can quench the urease fluorescence mainly through a static quenching procedure. The binding constant K and the number of binding site n were calculated according to the fluorescence quenching results. For metolachlor, K = 1.49 x 10(3) L x mol(-1) and n was 0.84; for S-isomer, K=2.22 x 10(3) L x mol(-1) and n was 0.89.

Adsorption and correlation with their thermodynamic properties of triazine herbicides on soils.

Adsorption of atrazine, prometryne and prometon was determined on six soils with different physical and chemical properties. The adsorption isotherms of three herbicides could well fit Freundlich equation. On all of six soils, adsorption of herbicides increased in the order: atrazine approximately = prometon < prometryne. This order is quite the same to the calculation result of by means of excess thermodynamic properties of triazine. The Freundlich adsorption constants, Kf, showed to have good correlation with organic matter (OM%) of soils for each of these herbicides, suggesting that OM is the main factor, which dominates in the adsorption process of these triazine herbicides.

Adsorption of chloroacetanilide herbicides on soil and its components. III. Influence of clay acidity, humic acid coating and herbicide structure on acetanilide herbicide adsorption on homoionic clays.

Adsorption of chloroacetanilide herbicides on homoionic montmorillonite, soil humic acid, and their mixtures was studied by coupling batch equilibration and FT-IR analysis. Adsorption isotherms of acetochlor, alachlor, metolachlor and propachlor on Ca(2+)-, Mg(2+)-, Al(3+)- and Fe(3+)-saturated clays were well described by the Freundlich equation. Regardless of the type of exchange cations, Kf decreased in the order of metolachlor > acetolachlor > alachlor > propachlor on the same clay. FT-IR spectra showed that the carbonyl group of the herbicide molecule was involved in binding, probably via H-bond with water molecules in the clay interlayer. The type and position of substitutions around the carbonyl group may have affected the electronegativity of oxygen, thus influencing the relative adsorption of these herbicides. For the same herbicide, adsorption on clay increased in the order of Mg2+ < Ca2+ < Al3+ < or = Fe3+ which coincided with the increasing acidity of homoionic clays. Acidity of cations may have affected the protonation of water, and thus the strength of H-bond between the clay water and herbicide. Complexation of clay and humic acid resulted in less adsorption than that expected from independent adsorption by the individual constituents. The effect varied with herbicides, but the greatest decrease in adsorption occurred at a 60:40 clay-to-humic acid ratio for all the herbicides. Causes for the decreased adsorption need to be characterized to better understand adsorption mechanisms and predict adsorption from soil compositions.