Flexible Bis Imidazole Ligands Research Articles

Two Mixed-ligand Coordination Polymers: Crystal Structures and Protective Effect on Ischemic Stroke by Increasing glp1r Expression.

In this study, two new mixed-ligand coordination polymers {[Co(bbi)(tdc)]·5H2O}n (1, bbi = 1,4-bis(imidazolyl)butane) and {[Cu2(bimb)(H2O)(μ3-tdc)2(DMF)2]·H2O}n (2, bimb = 4-bis(1H-imidazol-1-yl-methyl)benzene) were synthesized under the solvothermal conditions via reaction of 2,5-thiophenedicarboxylic acid (H2tdc) with the corresponding metal salts in the existence of different flexible bis-imidazole ligands (bbi for 1 and bimb for 2). The as-prepared two structures were detected via the single crystal X-ray diffraction (SXRD) and then characterized via the analysis of element, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) as well as infrared (IR) spectroscopy. Furthermore, the protective activity of the compound on the mice with ischemic stroke was evaluated. Firstly, the real time reverse transcription-polymerase chain raction (RT-PCR) was carried out to determine the effect of compounds 1 and 2 against the relative expression level of the glucagon-like peptide 1 receptors (glp1r) on the cerebrovascular endothelial cells. Next, the Morris Water Maze Experiment was also used to detect the improvement function of compounds 1 and 2 on the nice mice cognitive function.

A family of entangled coordination polymers constructed from a flexible bisimidazole ligand and versatile polycarboxylic acids: Syntheses, structures and properties

A family of entangled coordination polymers, namely, [Cd(cba)(ibpi)] (1), [Cd(sdc)(ibpi)]·H2O (2), [Cd2(bpdc)2(ibpi)2] (3), [Ni2(sdc)2(ibpi)2(H2O)2]·H2O (4), [Cd2(tdc)2(ibpi)]·H2O (5), [Cd(Hbtc)(ibpi)] (6), [Co2(tdc)2(ibpi)2·H2O]·2H2O (7) and [Cd2(cdc)2(ibpi)2]·2H2O (8). [ibpi=1-(4-(4-(1H-imidazol-1-yl)benzyloxy)phenyl)-1H-imidazole, H2cba=4,4′-carbonyldibenzoic acid, H2sdc=4,4′-sulfonyldibenzoic acid, H2bpdc=biphenyl-4,4′-dicarboxylic acid, H2cdc=1,4-cyclohexanedicarboxylic acid, H2tdc=thiophene-2,5-dicarboxyl acid, and H3btc=1,3,5-benzenetricarboxylic acid], have been synthesized and structurally characterized. Compound 1 exhibits a 2-fold parallel interpenetration of sql networks. Compound 2 presents a 3-fold parallel interpenetration of sql networks. Compound 3 features a parallel polycatenation of 3-fold interpenetrated sql networks. Compound 4 shows a unique type of inclined interpenetration of sql networks. Compound 5 displays a 3-fold interpenetration of pcu network. Compound 6 exhibits a uninodal self-catenating mab network. Compound 7 shows an 8-connected self-catenating framework of 8T10 topology with the point symbol (420·68). Compound 8 presents a unique 8-connected 8T21 self-catenating framework with the point symbol (424·64). The thermal stabilities and photochemical properties of compounds 1, 2, 3, 5, 6and8 have also been studied.

Synthesis, structure and photoluminescence of two cadmium coordination polymers with 1,3-benzenedicarboxylate and two flexible bis-imidazole ligands

Two new coordination polymers, [Cd 2(2-mBIM) 2(1,3-BDC) 2] n ( 1) and [Cd(BIM)(1,3-BDC)] n ( 2) [BIM = bis(imidazol-1-yl)-methane, 2-mBIM = bis(2-methylimidazol-1-yl)methane], were synthesized by reactions of CdCl 2 with 2-mBIM or BIM ligand in the presence of 1,3-benzenedicarboxylic acid. The polymers were then characterized by elemental analyses, IR, TGA, and X-ray diffraction. Compound 1 is a two-dimensional (2D) twofold parallel interpenetration network with a (4, 4) connected topology. Compound 2 is a 2D double-layer framework containing [Cd 2(COO) 4] subunits. The results of this study suggest that subtle changes in the ligand structure may have a great impact on the resulting architectures of the metal–organic frameworks. Solid-state luminescent spectra of compounds 1 and 2 indicate weak fluorescent emissions at ca. 389 and 302 nm, respectively.

Ag(I) coordination polymers with flexible bis-imidazole ligands: 2D interwoven structure and wavy layer network based on silver–silver interactions

Two new coordination polymers [Ag(BIM)SO 3CF 3] n ( 1) and [Ag(2-mBIM)NO 2] n ( 2) [wherein BIM = bis(imidazol-1-yl)-methane, 2-mBIM = bis(2-methylimidazol-1-yl) methane], were synthesized by the reactions of AgSO 3CF 3 with BIM and AgNO 2 with 2-mBIM, respectively. They were characterized by elemental analyses, IR, TGA and single crystal X-ray diffraction studies. Compound 1 is an example of silver coordination network with 2D fabric structure in a “one-over/one-under” fashion through weak Ag…Ag interactions. Compound 2 adopts a wavy 2D layer network constructed through the Ag…Ag interactions between each neighboring 1D zigzag chains. TGA measurements suggest that 1 and 2 are thermally quite stable, with decomposition temperatures being 355 °C and 230 °C, respectively. Solid state luminescent spectra of compounds 1 and 2 indicate weak fluorescent emissions at ca. 345 and 409 nm, respectively.