15658-60-3Relevant academic research and scientific papers
Investigations into the synthesis and fluorescence properties of Eu(III), Tb(III), Sm(III) and Gd(III) complexes of a novel bis-β-diketone-type ligand
Luo, Yi-Ming,Chen, Zhe,Tang, Rui-Ren,Xiao, Lin-Xiang,Peng, Hong-Jian
, p. 513 - 516 (2008)
A novel bis-β-diketon ligand, 1,1′-(2,6-bispyridyl)bis-3-phenyl-1,3-propane-dione (L), was designed and synthesized and its complexes with Eu(III), Tb(III), Sm(III) and Gd(III) ions were successfully prepared. The ligand and the corresponding metal comple
A highly sensitive pyridine-dicarbohydrazide based chemosensor for colorimetric recognition of Cu2+, AMP2-, F- and AcO- ions
Kumar, Rakesh,Jain, Harshita,Gahlyan, Parveen,Joshi, Ankita,Ramachandran
, p. 8567 - 8576 (2018)
A new pyridine-dicarbohydrazide based colorimetric chemosensor L1 is designed and synthesized for the detection of anions and cations. The chemosensor allows the 'naked-eye' recognition of toxic cation Cu2+ and biologically relevant anions AMP2-, F- and AcO- in DMSO/H2O (8/2, v/v) solution with a fast response time (～5 s). The selectivity, sensitivity and binding stoichiometry of L1 for the aforementioned ions are investigated using colorimetric, UV-Vis spectroscopic and 1H NMR studies. The binding mode is analyzed by UV-Vis and 1H NMR studies, which are supported by density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations. The optimized geometries indicate that the carbohydrazide moiety provides the binding site for the cation and anions. The HOMO-LUMO energy gap for the complex of AMP2- with L1 is least among all the complexes, possibly due to the charge-transfer effect. The detection limits of L1 for Cu2+ and AMP2- were determined to be 0.12 μM and 0.08 μM, respectively. Furthermore, the potential application of the sensor for the detection of fluoride ion in commercially available toothpaste was demonstrated successfully.
In search for mononuclear helical lanthanide building blocks with predetermined properties: Lanthanide complexes with diethyl pyridine-2,6-dicarboxylate
Renaud, Fabien,Piguet, Claude,Bernardinelli, Gerald,Buenzli, Jean-Claude G.,Hopfgartner, Gerard
, p. 1660 - 1667 (1997)
The ligand diethyl pyridine-2,6-dicarboxylate (L5) reacts with Ln(III) in acetonitrile to successively give the complexes [Ln(L5)'1]3+ (Ln = La to Lu, i =1-3). Spectroscopic investigations (ES-MS, UV/Vis, NMR) show that the 1:3 complexes [Ln(L5)3]3+ have poor stability in solution and exist as a mixture of rapidly interconverting conformers. Variable-temperature NMR data show that the helical P? M interconversion and dynamic on-off equilibria of the ester side arms both control the observed average structure in solution. Contrary to similar lanthanide building blocks possessing benzimidazole or carboxamide side arms, [Eu(L5)3]3+ has a sizable quantum yield in anhydrous acetonitrile; this has been attributed to an improved ligand → Eu(III) energy transfer resulting from a good energetic match between the ligand- and metal-centered excited states. Pure 1:3 complexes cannot be isolated in the solid state, but crystalline 1:2 complexes [Ln(L5)2](TfO)3 · nH2O have been prepared. The X-ray crystal structure of [Eu(L5)2(TfO)2(OH2)]TfO (1) reveals two meridionally tricoordinated ligands L5, but the long Eu-O(ester) bonds imply only weak interactions between the carbonyl groups of the ester side arms and Eu(III), providing a limited protection of the metallic site. The photophysical studies show that nonacoordinate Eu(III) in 1 binds an additional water molecule to give a decacoordinate complex in the solid state, thus confirming the accessibility of the metallic site for further complexation.
Pyridine-imide oligomers
Li, Xiao,Zhan, Chuanlang,Wang, Yaobing,Yao, Jiannian
, p. 2444 - 2446 (2008)
Pyridine-imide oligomers created by incorporating imide and pyridine units alternatively in sequence were successfully synthesized and found to form highly compact and stable helical conformations contributed by intramolecular H-bonds between the imide and both adjacent pyridines, and by the structural characteristics of the imide units. The Royal Society of Chemistry.
Highly sensitive and selective "naked eye" sensing of Cu(ii) by a novel amido-imine based receptor: A spectrophotometric and DFT study with practical application
Bhattacharyya, Arghyadeep,Ghosh, Soumen,Guchhait, Nikhil
, p. 28194 - 28199 (2016)
We report the synthesis of a novel compound (E)-bis-N′-((1H-pyrrol-2-yl)methylene)-pyridine-2,6-carbohydrazide and its sensing ability to detect copper(ii) ion in aqueous medium by a sharp color change from yellow to brown, the sensing limit being 4.0 × 10-9 M. Theoretical modeling of the compound and its copper complex was performed. Practical utility was explored by successful paper strip response.
Picolinic acid based acyclic bifunctional chelating agent and its methionine conjugate as potential SPECT imaging agents: Syntheses and preclinical evaluation
Kadiyala, K. Ganesh,Tyagi, Tulika,Kakkar, Dipti,Chadha, Nidhi,Chuttani, Krishna,Roy, Bal Gangadhar,Thirumal, Meganathan,Mishra, Anil K.,Datta, Anupama
, p. 33963 - 33973 (2015)
Bifunctional chelate, 6,6′-(2-aminoethylazanediyl)bis(methylene)dipicolinic acid (H2pentapa-en-NH2), has been synthesized and labeled with 99mTc with a specific activity of 135-140 MBq μmol-1 in >95% yield. The in vitro stability of the labeled chelate in both PBS and human serum shows only -1 uptake in other organs. The target specificity of the chelate towards tumor was introduced by conjugating two molecules of methionine. The conjugated probe H2pentapa-en-met2 was synthesized in >85% yield and labeled with 99mTc in 96.2% radiochemical yield with a specific activity of 110-125 MBq μmol-1. The conjugate probe exhibited high serum stability (>94% at 24 h). The in vivo blood kinetic studies of radiocomplexes of H2pentapa-en-NH2 and its methionine conjugated derivative exhibited fast clearance with t1/2(F) = 32 ± 0.14 min, t1/2(S) = 4 h 20 min ± 0.21 min and t1/2(F) = 27 ± 0.3 min, t1/2(S) = 4 h 01 min ± 0.11 min, respectively. In vivo scintigraphy and ex vivo biodistribution studies in EAT tumor bearing mice demonstrated a high retention of H2pentapa-en-met2 at the site of the tumor with tumor to muscle ratio of 6.52 at 1 h, indicating the high specificity of 99mTc-pentapa-en-met2 toward tumors.
2,6-Bis(5-(2,2-dimethylpropyl)-1H-pyrazol-3-yl)pyridine as a ligand for efficient actinide(III)/lanthanide(III) separation
Bremer, Antje,Ruff, Christian M.,Girnt, Denise,Muellich, Udo,Rothe, Joerg,Roesky, Peter W.,Panak, Petra J.,Karpov, Alexei,Mueller, Thomas J. J.,Denecke, Melissa A.,Geist, Andreas
, p. 5199 - 5207 (2012)
The N-donor complexing ligand 2,6-bis(5-(2,2-dimethylpropyl)-1H-pyrazol-3- yl)pyridine (C5-BPP) was synthesized and screened as an extracting agent selective for trivalent actinide cations over lanthanides. C5-BPP extracts Am(III) from up to 1 mol/L HNO3 with a separation factor over Eu(III) of approximately 100. Due to its good performance as an extracting agent, the complexation of trivalent actinides and lanthanides with C5-BPP was studied. The solid-state compounds [Ln(C5-BPP)(NO3)3(DMF)] (Ln = Sm(III), Eu(III)) were synthesized, fully characterized, and compared to the solution structure of the Am(III) 1:1 complex [Am(C5-BPP)(NO3) 3]. The high stability constant of log β3 = 14.8 ± 0.4 determined for the Cm(III) 1:3 complex is in line with C5-BPP's high distribution ratios for Am(III) observed in extraction experiments.
Bioconjugation of proteins with a paramagnetic NMR and fluorescent tag
Huang, Feng,Pei, Ying-Ying,Zuo, Hui-Hui,Chen, Jia-Liang,Yang, Yin,Su, Xun-Cheng
, p. 17141 - 17149 (2013)
Site-specific labeling of proteins with lanthanide ions offers great opportunities for investigating the structure, function, and dynamics of proteins by virtue of the unique properties of lanthanides. Lanthanide-tagged proteins can be studied by NMR, X-ray, fluorescence, and EPR spectroscopy. However, the rigidity of a lanthanide tag in labeling of proteins plays a key role in the determination of protein structures and interactions. Pseudocontact shift (PCS) and paramagnetic relaxation enhancement (PRE) are valuable long-range structure restraints in structural-biology NMR spectroscopy. Generation of these paramagnetic restraints generally relies on site-specific tagging of the target proteins with paramagnetic species. To avoid nonspecific interaction between the target protein and paramagnetic tag and achieve reliable paramagnetic effects, the rigidity, stability, and size of lanthanide tag is highly important in paramagnetic labeling of proteins. Here 4′-mercapto-2, 2′: 6′,2′′-terpyridine-6,6′′-dicarboxylic acid (4MTDA) is introduced as a a rigid paramagnetic and fluorescent tag which can be site-specifically attached to a protein by formation of a disulfide bond. 4MTDA can be readily immobilized by coordination of the protein side chain to the lanthanide ion. Large PCSs and RDCs were observed for 4MTDA-tagged proteins in complexes with paramagnetic lanthanide ions. At an excitation wavelength of 340 nm, the complex formed by protein-4MTDA and Tb3+ produces high fluorescence with the main emission at 545 nm. These interesting features of 4MTDA make it a very promising tag that can be exploited in NMR, fluorescence, and EPR spectroscopic studies on protein structure, interaction, and dynamics. Rigid and small: Rigidity and small size of lanthanide-binding tags are critically important in site-specific labeling of proteins with lanthanide ions. 4′-Mercapto-2,2′:6′,2′′-terpyridine-6, 6′′-dicarboxylic acid (4MTDA) provides five coordination sites for lanthanide ions and can be readily immobilized by coordination of proteins (see figure).
A molecular chain of four CoII ions stabilized by a tris-pyridyl/Bis - βdiketonate ligand
Barrios, Leoni A.,Aguila, David,Roubeau, Olivier,Murray, Keith S.,Aromi, Guillem
, p. 1130 - 1136 (2009)
The synthesis and characterization of a tris-pyridyl/bis - diketone molecule (H2L) is reported. This compound acts as a hexadentate ligand towards CoII to facilitate the assembly of a tetranuclear molecular chain of closely spaced metals with formula [Co4L 2(MeOH)8](NO3)4 (1), which exhibits a very flat [Co4L2]4+ platform, as determined by single-crystal X-ray diffraction crystallography. Complex 1 readily exchanges axial methanol ligands with water molecules. The bulk magnetization of the resulting hydrate, 1a, shows that the metals in the [Co4L 2]4+ moiety exhibit spin-orbit coupling and antiferromagnetic exchange interactions. CSIRO 2009.
Imidazole for Pyridine Substitution Leads to Enhanced Activity under Milder Conditions in Cobalt Water Oxidation Electrocatalysis
McMillion, Noah D.,Wilson, Amanda W.,Goetz, McKenna K.,Chang, Mu-Chieh,Lin, Chia-Cheng,Feng, Wei-Jie,McCrory, Charles C. L.,Anderson, John S.
, p. 1391 - 1397 (2019)
A previously reported cobalt complex featuring a tetraimidazolyl-substituted pyridine chelate is an active water oxidation electrocatalyst with moderate overpotential at pH 7. While this complex decomposes rapidly to a less-active species under electrocatalytic conditions, detailed electrochemical studies support the agency of an initial molecular catalyst. Cyclic voltammetry measurements confirm that the imidazolyl donors result in a more electron-rich Co center when compared with previous pyridine-based systems. The primary changes in electrocatalytic behavior of the present case are enhanced activity at lower pH and a marked dependence of catalytic activity on pH.
