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Abstract: A new multifunctionalized phosphoric acid, (2-(diphosphonomethylamino)nicotinic acid, Py(COOH)(NHCH(PO3H2)2), H5 L 1), has been employed as ligand for the construction of new metal phosphonates. By reacting it with different metal chlorides under hydrothermal condition, three new transition metal phosphonates, namely, [Co2(HL 1)(H2O)5][H2O]3 (1), Zn(H3 L 1) (2) and [Cd(H3 L 1)(H2O)2][H2O] (3) were successfully obtained. The single-crystal structure measurements indicated that the coordination mode of ligand H5 L 1 is metal-dependant and results in different structures. For compound 1, it features 2D layered structure. Whereas compounds 2 and 3 have 1D chain structures. Under the excitation of 250nm light, both compounds 2 and 3 show intraligand and ligand to metal charge transfer (LMCT) emission bands at about 415 and 420nm, respectively. Magnetic study shows that compound 1 displays antiferromagnetic behavior. [Copyright &y& Elsevier]

Abstract: Hydrothermal reactions of different lanthanide(III) salts with an amino-diphosphonate ligand (H4L=C6H5CH2N(CH2PO3H2)2) led to two series of lanthanide phosphonates, namely, Ln(H2L)(H3L) (Ln=La, 1; Pr, 2; Nd, 3; Sm, 4; Eu, 5; Gd, 6; Tb, 7). Compounds 1–5 feature a one-dimensional (1D) chain structure in which dimers of two edge-sharing LnO8 polyhedra are interconnected by bridging phosphonate groups, such 1D arrays are further interlinked via strong hydrogen bonds between non-coordinated phosphonate oxygen atoms into a two-dimensional (2D) layer with the phenyl groups of the ligands orientated toward the interlayer space. Compounds 6 and 7 also show a different 1D array in which the LnO6 octahedra are bridged by phosphonate groups via corner-sharing, such chains are also further interlinked by hydrogen bonds into a 2D supramolecular layer. Compounds 5 and 7 emit red and green light with a lifetime of 2.1 and 3.7ms, respectively. [Copyright &y& Elsevier]

As primary polymer material in industrial products, bisphenol A (BPA) has become one of the most productive chemicals. Excluding its endocrine-disrupting property, BPA can also produce excessive reactive oxygen species (ROS). Nevertheless, the underlying toxic mechanisms of BPA-induced oxidative damages to plants are still unknown. In this work, glutathione S-transferase Phi8 was used as biomarker to evaluate the hazardous oxidative effects of BPA at the molecular level. Firstly, the intrinsic fluorescence of AtGSTF8 was statically quenched along with complex formation and structural and conformational changes, which led to the loosening and unfolding of the framework of AtGSTF8 as well as the increase of hydrophilicity around Trp residues. Then a single binding site was predicted for AtGSTF8 towards BPA and the complex formation was predominantly driven by hydrophobic interactions owing to the positive ΔH and ΔS. Besides, the predicted binding site of BPA was close to the H-site of AtGSTF8 which was surrounded by several hydrophobic amino acids based on the molecular docking results. The activity of glutathione S-transferase was declined and the plant growth was destroyed upon complex formation. The investigation of the binding mechanism of BPA with AtGSTF8 at molecular level would provide experimental assessments on toxicological effects of BPA on plants. [Display omitted] • The interaction mechanism of BPA with AtGSTF8 was investigated for the first time. • BPA exhibits the evident effects on the structure and function of AtGSTF8. • This study evaluates the toxicity of BPA and forecast the related effects on plants. [ABSTRACT FROM AUTHOR]

The adverse effects of tetracycline (TC), chlortetracycline (CTC) and oxytetracyline (OTC) residues on human health and ecosystem have attracted much attention. Herein, two novel luminescent phosphonate metal-organic frameworks based on Zn and Cd were prepared by hydrothermal method, named MOF-1 (2[Zn 2 ‧L·(H 2 O) 2 ]) and MOF-2 (2[Cd(H 2 L)‧(H 2 O) 2 ]), respectively. Two MOFs can specifically recognize three antibiotics and quench the fluorescence by the internal filter effect (IFE). In addition, in the presence of ions and other antibiotics, the MOFs still showed good selectivity and strong anti-interference performance. It is worth noting that the detection limits of MOF-2 for TC, CTC and OTC are 4.9, 1.21 and 2.17 ​nM respectively. These excellent sensing properties, together with easy preparation, good stability and feasibility, makes MOFs have high potential to detect tetracycline antibiotics in aqueous solution. [Display omitted] • Two MOFs sensors based on phosphonate ligand were prepared by hydrothermal method. • Two MOFs sensors have a wide response range and low LOD. • Two MOFs sensors has excellent anti-interference ability. [ABSTRACT FROM AUTHOR]

Four rare earth carboxylates, namely [Y(L) (DMF) (H 2 O)]·H 2 O (1), Y(L) (H 2 O) (2), La(L) (DMF) (3) and La(L) (H 2 O) (4), have been hydro/solvothermally synthesized from 2-(6-carboxypyridin-2-yl)terephthalic acid (H 3 L) and systematically characterized using IR, EA, single-crystal and powder X-ray diffraction, luminescence methods. The structural characterizations reveal that the crystal structures of rare earth carboxylates can be effectively altered by judicious alteration of the synthesis conditions. These complexes are very stable and display intense intraligand emissions. Four rare earth carboxylates with interesting crystal structures have been synthesized from a rigid polydentate carboxylate ligand containing pyridine group and systematically characterized. Image 1 [ABSTRACT FROM AUTHOR]