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Two water-stable Cd(II)-MOFs, [CdL 0.5 (H 2 O)] (1) and {[Cd 3 (H 2 L)(dtb) 2 (H 2 O)]·3H 2 O} n (2) [H 4 L ​= ​1,1'-(ethane-1,2-diyl)bis (1H-imidazole-4,5-dicarboxylic acid); H 2 dtb ​= ​1,4-di (1H-tetrazol-5-yl)benzene) has been hydrothermally synthesized and characterized by elemental analyses, IR, TG, and X-ray single-crystal diffraction. Complex 1 exhibits a 3D 6-connected framework based on L4− ligands μ 6 -linking [Cd 2 O 2 ] unit, and complex 2 possesses a 3D (3,8)-connected porous framework built by H 2 L2− and dtb2− ligands bridging [Cd 3 O 2 ] units. The luminescence properties were investigated, showing that 1 and 2 can display high sensitivity and selectivity for detecting Fe3+, Cr(VI) and MnO 4 − ions in aqueous solutions via luminescence quenching effects. Furthermore, possible sensing mechanism was investigated in this paper. Two water-stable luminescent Cd(II)-MOFs has been hydrothermally synthesized by using a new flexible ligand (H 4 L) containing two H 2 IDC groups. Complex 1 exhibits a 3D 6-connected framework based on L4− ligands μ 6 -linking [Cd 2 O 2 ] unit, and complex 2 possesses a 3D (3,8)-connected porous framework built by H 2 L2− and dtb2− ligands bridging [Cd 3 O 2 ] units. Luminescence sensing performances reveal that two complexes behave satisfactory recognition and detection effect toward Fe3+, Cr(VI) and MnO 4 − ions with low detection limit and high sensitivity, which may be acted as potential multi-responsive luminescence sensing materials. Furthermore, possible sensing mechanism was investigated in this paper. [Display omitted] • A new ligand containing two H 2 IDC groups was firstly employed to construct MOFs. • Two water-stable Cd(II)-MOFs have been hydrothermally synthesized. • Complexes 1 and 2 exhibited 3D porous frameworks, respectively. • Both 1 and 2 displayed potential multi-responsive luminescence sensing capabilities. [ABSTRACT FROM AUTHOR]

In this paper, a zinc(II)-based coordination polymer, Zn 2 [(C 6 H 8 (COOH) 2 ] 2 (1) [(C 6 H 8 (COOH) 2 ​= ​1,2-cyclopentanedicarboxylic acid, CPDA)], was successfully synthesized by solvothermal method. Thereafter, 1 was characterized by single crystal and powder X-ray diffraction, elemental analysis, thermogravimetric analysis and infrared spectrum techniques. In the hypoglycemic experiment, the results showed that 1 could effectively increase the glucose uptake in insulin resistance (IR)-type HepG2 cells. Besides, 1 displayed favorable antidiabetic activity in contrast to the Zinc nitrate and the CPDA ligand. The mechanism of 1 to alleviate insulin resistance might be related to the reduction of the intracellular reactive oxygen species (ROS) level and the regulation of the ROS/JNK/AKT signaling pathway. Zn 2 (CPDA) 2 alleviated the insulin resistance by reducing of the intracellular reactive oxygen species (ROS) level and the regulation of the ROS/JNK/AKT signaling pathway. [Display omitted] •A zinc-based coordination polymer, [Zn 2 (CPDA) 2 ] (1), was synthesized. • 1 was found to have high antidiabetic effect to HepG2 cells. •The antidiabetic mechanism might be related to the ROS production. [ABSTRACT FROM AUTHOR]

The three multi-dimensional coordination polymers, [Mn 2 (μ 4 -dttpa)(μ 6 -dttpa)(H 2 O) 2 ] n (1), {[Co(μ 4 -dttpa)(H 2 O) 2 ]·2H 2 O} n (2), and {[Zn 3 (μ 4 -dttpa) 2 (μ 2 -dttpa)(phen) 2 (H 2 O) 2 ]·2H 2 O} n (3) (H 2 dttpa ​= ​2,5-di(1H-1,2,4-triazol-1-yl)terephthalic acid; phen ​= ​1,10- phenanthroline), are successfully synthesized and characterized by X-ray single crystal diffraction, powder X-ray diffraction (PXRD), FT-IR spectra, elemental analysis and thermogravimetric analysis. Structurally, complex 1 is a three-dimensional structure with the 3-nodal Schläfli point symbol of {4·63·82} 2 {42·62·82}{62·84}. Complex 2 displays a two-dimensional network with a 6-connected uninodal net. With the point symbol of {4·62} 2 ·{43·63} 2 ·{44·62}{6}, complex 3 shows the two-dimensional stacking pattern. Temperature-dependent magnetic data of complexes 1 and 2 indicate antiferromagnetic behaviors between adjacent metal ions from 2 ​K to 300 ​K. Further magnetic studies show that the best fitting parameters of comple× 1 are obtained using the dinuclear Mn(II) model. From 50K to 300K, complex 2 displays antiferromagnetism over its mononuclear analogue with the zero-field splitting parameter (|D| ​= ​35.2 ​cm−1). The luminescent intensity of complex 3 is much stronger than that of free ligand (H 2 dttpa) and auxiliary ligand (phen). Moreover, the photoluminescence mechanism of complex 3 has been analyzed by theoretical calculation at ωB97XD/6–311++g(2d,p) level with DFT and TDDFT, which reveals that luminescence emission of 3 is attributed to the ligand-to-ligand charge transfer (π∗ phen -π dttpa2-). Compared with the free ligand, the enhancement of the luminescent intensity of compound 3 might occur due to the construction of Zn(II) ion, dttpa2− and phen increases the efficiency of charge transfer between LUMO and HOMO in the solid state. [Display omitted] • The luminescence mechanism of Zinc(II) compound has been elaborated by DFT and TDDFT analysis. • Summary and comparison of dttpa2− complexes in this paper and published in literature. • A new coordination mode μ 2 -(η1)-(η1) of dttpa2− in the solid state is first published. [ABSTRACT FROM AUTHOR]