1118-67-8Relevant articles and documents
Metal-Anion Coordination and Linker-Anion Hydrogen Bonding in the Construction of Metal-Organic Frameworks from Bipyrazole
Zhang, Erpan,Jia, Qizhang,Zhang, Jun,Ji, Zhenguo
, p. 191 - 195 (2016)
Two new two-dimensional frameworks based on packing of square grids, Cu(Me4bpz)2(NO3)2 (1) and Zn(Me4bpz)(SO4) (2) (Me4bpz=3,3′,5,5′-tetramethyl-4,4′-bipyrazole), have been synthesized by mild solvothermal method. In addition to the major metal-organic linker coordination, they allow us to study how the metal-inorganic anion coordination and organic linker-inorganic anion hydrogen bonding affect the resulting structures during the framework assembly. Two new MOFs based on bipyrazole were synthesized, and they provide examples of metal-anion coordination and linker-anion hydrogen bonding during the framework assembly.
Bioinspired models for an unusual 3-histidine motif of diketone dioxygenase enzyme
Ramasubramanian, Ramamoorthy,Anandababu, Karunanithi,M?sch-Zanetti, Nadia C.,Belaj, Ferdinand,Mayilmurugan, Ramasamy
, p. 14326 - 14336 (2019)
Bioinspired models for contrasting the electronic nature of neutral tris-histidine with the anionic 2-histidine-1-carboxylate facial motif and their subsequent impact on catalysis are reported. Herewith, iron(ii) complexes [Fe(L)(CH3CN)3](SO3CF3)21-3 of tris(2-pyridyl)-based ligands (L) have been synthesized and characterized as accurate structural models for the neutral 3-histidine triad of the enzyme diketone dioxygenase (DKDO). The molecular structure of one of the complexes exhibits octahedral coordination geometry and Fe-N11py bond lengths [1.952(4) to 1.959(4) ?] close to the Fe-NHis bond distances (1.98 ?) of the 3-His triad in the resting state of the enzyme, as obtained by EXAFS studies. The diketonate substrate-adduct complexes [Fe(L)(acacR)](SO3CF3) (R = Me, Ph) of 1-3 have been obtained using Na(acacR) in acetonitrile. The Fe2+/3+ redox potentials of the complexes (1.05 to 1.2 V vs. Fc/Fc+) and their substrate adducts (1.02 to 1.19 V vs. Fc/Fc+) appeared at almost the same redox barrier. All diketonate adducts exhibit two Fe(ii) → acac MLCT bands around 338 to 348 and 430 to 490 nm. Exposure of these adducts to O2 results in the decay of both MLCT bands with a rate of (kO2) 5.37 to 9.41 × 10-3 M-1 s-1. The kO2 values were concomitantly accelerated 20 to 50 fold by the addition of H+ (acetic acid), which nicely models the rate enhancement in the enzyme kinetics by the glutamate residue (Glu98). The oxygenation of the phenyl-substituted adducts yielded benzoin and benzoic acid (40% to 71%) as cleavage products in the presence of H+ ions. Isotope-labeling experiments using 18O2 showed 47% incorporation of 18O in benzoic acid, which reveals that the oxygen originates from dioxygen. Thus, the present model complexes exhibit very similar chemical surroundings to the active site of DKDO and mimic its functions elegantly. On the basis of these results, the C-C bond cleavage reaction mechanism is discussed.
Synthesis and characterization of Pd(II) antitumor complex, DFT calculation and DNA/BSA binding insight through the combined experimental and theoretical aspects
Feizi-Dehnayebi, Mehran,Dehghanian, Effat,Mansouri-Torshizi, Hassan
, (2021)
A novel palladium(II) complex, [Pd(bpy)(acac)]NO3 (where bpy and acac are 2,2′-bipyridine and acetylacetonato), has been synthesized and fully characterized through 1H NMR, UV-Vis and FT-IR spectra, conductivity measurement and elemental analysis. Geometry optimization using DFT calculation demonstrated that a square-planar geometry is built around Pd(II) atom. The MEP and FMO analysis were also applied. Partition coefficient evaluation was conducted to determine the lipophilicity of the compound which follows the order complex > cisplatin. The antitumor activity of the complex has been evaluated on K562 cancer cells by MTT method, which exhibited an appropriate activity in compare to cisplatin. The interaction of [Pd(bpy)(acac)]NO3 towards biomolecules (CT-DNA and BSA) was investigated through in-detail fluorescence, UV–Vis and other techniques. The findings of fluorescence titration demonstrated that the Pd(II) complex binds to CT-DNA via hydrophobic and with BSA through van der Waals forces and hydrogen bond. UV–Vis experiment revealed a reduction in the absorption spectra of biomolecules in presence of the complex. The binding affinity was further endorsed for CT-DNA utilizing viscosity measurement and gel electrophoresis and for BSA via CD spectroscopy and FRET calculation. In addition, molecular docking supports the findings of experiments and indicates that the Pd(II) complex appears to be situated at DNA intercalation position and BSA Sudlow's site I. All results have shown that this compound may be a useful potential antitumor candidate for further medical purposes.
West,Riley
, p. 295,298,300 (1957)
Oxidative Mechanochemistry: Direct, Room-Temperature, Solvent-Free Conversion of Palladium and Gold Metals into Soluble Salts and Coordination Complexes
Do, Jean-Louis,Tan, Davin,Fri??i?, Tomislav
supporting information, p. 2667 - 2671 (2018/02/06)
Noble metals are valued, critical elements whose chemical activation or recycling is challenging, and traditionally requires high temperatures, strong acids or bases, or aggressive complexation agents. By using elementary palladium and gold, demonstrated here is the use of mechanochemistry for noble-metal activation and recycling by mild, clean, solvent-free, and room-temperature chemistry. The process leads to direct, efficient, one-pot conversion of the metals, including spent catalysts, into either simple water-soluble salts or metal–organic catalysts.
