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• A novel molecular coordination compound and one known compound have beeen synthesized and they were obtained from V 2 O 5 and 2,6-pyridinedicarboxylic acid (H 2 DPA). • They were characterized by IR spectroscopy, manganometric titration, magnetic susceptibility, thermogravimetric and single crystal XRD analyses. • The single-crystal XRD analysis revealed that compound 1 was a molecular consist of four-nuclear coordination compound. • The results of antimicrobial activity show that they have an antimicrobial effect against the microorganisms P. aeruginosa, E. coli, S. aureus, E. faecalis, L. monocytogenes, B.subtilis, C. albicans. A novel molecular coordination compound, [ V 4 IV O 4 (DPA) 4 (OH 2) 4 ]∙2H 2 O, 1 , and known [VIVO(DPA)(OH 2) 2 ].2H 2 O compound, 2 , were obtained from V 2 O 5 and 2,6-pyridine dicarboxylic acid (H 2 DPA) reactions with water or ethyl alcohol by using hydro/solvothermal synthetic methods. 1 was fully characterized by IR spectroscopy, manganometric titration, magnetic susceptibility, thermogravimetric and single crystal XRD analyses. The single-crystal XRD analysis revealed that it was a molecular consist of four-nuclear coordination compound. DPA ligand in 1 acted chelating and bridging modes through carboxylate groups. Four V(IV) ions exhibit a distorted octahedral coordination geometry {VNO 5 }. 1 and 2 were investigated for antimicrobial activity. The results of antimicrobial activity show that they have an antimicrobial effect against the microorganisms P. aeruginosa, E. coli, S. aureus, E. faecalis, L. monocytogenes, B.subtilis, C. albicans. [ABSTRACT FROM AUTHOR]

• Up to 98 % extraction of protonated 2,5-PDCA with tri-n-octylamine. • Up to 98 % extraction of deprotonated 2,5-PDCA with Aliquat 336. • 95 % re-extraction of 2,5-PDCA from organic phase by pH swing. • Continuous extraction in liquid–liquid centrifuges with 3.6-fold concentration. • 65 % recovery of 2,4-PDCA from fermentation broth in one step. Pyridinedicarboxylic acids (PDCA) are analogues to terephthalic acid and promising molecules for the production of bio-based plastics. Previous work achieved the microbial production of PDCAs from the renewable resource lignin but an efficient and low cost method to recover PDCA from fermentation broth is still missing. Reactive extraction is commonly applied for the extraction of carboxylic acids from aqueous phase. In this study, we investigate reactive extraction of PDCA with the two extractants tri-n-octylamine (TOA) and Aliquat 336 in the diluent 1-octanol. The extraction and re-extraction were optimized with 2,5-PDCA in an aqueous solution leading to up to 98 % extraction for both extractants. Re-extraction by pH swing resulted in > 95 % re-extracted 2,5-PDCA. A scale-up in liquid–liquid centrifuges enabled continuous extraction and re-extraction in liter scale with a yield of 95 %. A concentration factor of 3.6 was achieved and the organic phase was recycled. The approach also showed transferability to the processing of complex fermentation solution. 2,4-PDCA, microbially produced in a bioprocess, could be recovered by 65 % in one single extraction and re-extraction step from biomass-free fermentation broth. [ABSTRACT FROM AUTHOR]

In the presented work the thermal, theoretical (DFT) and spectroscopic (IR, Raman, NMR) properties of alkali metal complexes with quinolinic acid (2,3-pyridinedicarboxylic acid) and dipicolinic acid (2,6-pyridinedicarboxylic acid) were studied. The IR and Raman spectra were registered and analyzed in the range of 400–4000 cm−1. 1H NMR and 13C NMR spectra of analyzed compounds have been registered and assigned. The electronic charge distribution for the studied acids and their salts with lithium, sodium and potassium was calculated. All the calculations were done in the frame of density functional theory (DFT) using 6-311++G(d,p) basis set. The thermal decomposition of the analyzed compounds was done. [ABSTRACT FROM AUTHOR]

The metal(II) ion complexes of a pentadentate macrocycle 1, namely 3,12-dioxa-6,9,18-triazabicyclo[12.3.1]octadeca-1(18),14,16-triene-2,13-dione are synthesized. This macrocycle is prepared from the reaction of dipotassium salt of 2,6-pyridinedicarboxylic acid with ethylenediamine and 1,2-dibromoethane. The reaction of 1 (L) in methanol with MCl2.xH2O gave complexes with the general formula [M(L)Cl2] (where M= Ni(II) 2, Cu(II) 3 and Zn(II) 4, respectively). The analysis of IR, 1H- and 13C-NMR spectral data of all complexes propose that 1 is bonded to metal(II) ions through a nitrogen atom of pyridine ring, two nitrogen atoms of amine groups and two oxygen atoms of ester moieties. The thermal analysis indicated that there are no water molecules of hydration or coordinated in the structure of the complexes. Among these complexes, the Cu(II) 3 complex demonstrated good antibacterial and antifungal activities. The molecular geometry, AIM atomic charge and frontier molecular orbitals of the compounds are investigated theoretically using DFT method. Based on the theoretical data of these complexes represented, a bipyramidal pentagonal arrangement can be envisaged in such a way that the N3O2 pentadentate donor sites form the planar pentagonal base of the bipyramid and the two Cl atoms occupy the vertexes.

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A novel lanthanide complex [La(2,5-PA)(2,5-HPA)(H2O)2]n · nH2O (I) (2,5-H2PA = 2,5-pyridinedicarboxylic acid) was synthesized by a hydrothermal reaction and structurally characterized by singlecrystal X-ray diffraction (СIF file CCDC no. 1570808). Complex I is characteristic of a two-dimensional (2D) layered structure with the La3+ ion coordinating with seven oxygen atoms and two nitrogen atoms to yield a slightly distorted monocapped square antiprism. The [La(2,5-PA)(2,5-HPA)(H2O)2]n layers and lattice water molecules interlink together through hydrogen bonding interactions to give a three-dimensional (3D) supramolecular framework. Photoluminescence measurements under room temperature with solidstate samples show that it displays an emission in the green region of the light spectrum. Solid-state UV-Vis spectrum conducted with solid-state samples reveals the existence of a wide optical band gap of 3.57 eV. [ABSTRACT FROM AUTHOR]

Treatment of [RuCl2(PPh3)3] with equimolar amounts of 2,4-pyridinedicarboxylic acid (2,4-dipicH2) in the presence of Et3N afforded a tetranuclear complex [Ru( μ-2,4-dipic)(PPh3)2]4 ( 1) as red crystals. The crystal and molecular structure of [Ru( μ-2,4-dipic)(PPh3)2]4·CHCl3·8H2O ( 1·CHCl3·8H2O) was determined by single-crystal X-ray diffraction. Each ruthenium center in 1 is six-coordinated with two phosphorus atoms from triphenylphosphine ligands, one nitrogen atom from a pyridyl moiety and three oxygen atoms from two 2,4-dipic2- ligands. 2,4-Pyridinedicarboxylate dianions (2,4-dipic2-) act as bridging ligands to form the stable tetranuclear metallamacrocyclic compound. The electrochemical properties of 1 were also investigated. [ABSTRACT FROM AUTHOR]

An organic–inorganic hybrid supramolecular complex, (H3O)4[(CoC14H12N2O10)1.5(SiW12O40)]·2H2O, is constructed by tungstosilicate anion and 2,3-pyridinedicarboxylic acid cobalt coordination complex via intermolecular forces. Crystal data of the title complex: trigonal system,P-3c1space group,a = 20.363(3) Å,b = 20.363(3) Å,c = 27.685(5) Å,? = 90 °,? = 90 °,? = 90 °,V = 9942(3) Å3,Z = 4,Rint = 0.0383,R2 = 0.1645, GOOF = 1.083. The complex has been hydrothermally synthesized and characterized by Infrared spectra, TG-DTA, fluorescence, cyclic voltammetry, and single-crystal X-ray diffraction. The complex exhibits good catalytic activity for elimination of methanol in the gas phase, when the initial concentration of methanol is 2.76 g m?3, and flow rate is 10 mL min?1at 140 °C, the elimination rate of methanol is 82.6% over 0.2 g of complex. Catalytic performance [ABSTRACT FROM AUTHOR]

Previously we have developed a method, which uses two criteria, 'time to flower opening' and 'vase life', for characterizing flower opening profiles in cut spray-type flowers of carnation. These two criteria were used to evaluate the activities of flower preservatives, which accelerate flower bud opening, resulting in shortening the time to flower opening, and delay senescence, resulting in extension of vase life. In the present study, we developed the third criterion 'gross flower opening' which characterizes the ability of flower buds to open. Using this criterion the activity of analogs of pyridinedicarboxylic acids was successfully evaluated in addition to the previously-reported evaluation of their activity of acceleration of flower bud opening and extension of vase life. [ABSTRACT FROM AUTHOR]

Four new 3d-4f heterometallic coordination polymers [CuEu(2,5-pydc)(HO)]·4(HO) ( 1), [ZnEu(2,5-pydc)(HO)]·3(HO) ( 2), and [CoLn(2,6-pydc)(HO)]·4(HO) (Ln = Eu, 3; Dy, 4) (Hpydc = pyridinedicarboxylic acid) have been synthesized and characterized. All of these compounds have extended 3D coordination frameworks containing supramolecular 1D channels, in which lattice water molecules are located. Hydrogen bonds stabilize the 3D frameworks. Additionally, a study of their fluorescence properties has indicated that compounds 1 and 2 show the characteristic transitions of Eu. Weak antiferromagnetic interactions are observed in compound 3. [ABSTRACT FROM AUTHOR]

Abstract: A 3D uranium-pyridinedicarboxylate, compound (1) [UO2(C7H3NO4)], represents the final member of a series of materials incorporating a series of 2,n-pyridinedicarboxylic (pydc) acids (n=3,4,5,6). The resulting crystal structure [FW=419.13, monoclinic, P2 1 /n, a =9.0096(3) Å, b =8.1371(2) Å, c =11.6954(4) Å, V =852.45 Å3, Z=4] was determined by single crystal X-ray diffraction and fluorescent properties were investigated. Additionally, the complete series of uranium-2,n-pydc materials was examined on a basis of fluorescent behaviors and architectural similarities. [Copyright &y& Elsevier]

Abstract: A series of new triorganotin(IV) pyridinedicarboxylates [(C2H5)3NH][(Me3Sn)3(2,6-pdc)2(H2O)2] (1), [(C2H5)3NH][(Ph3Sn)3(2,6-pdc)2(H2O)2] (2), [(C2H5)3NH]{[(PhCH2)3Sn]3(2,6-pdc)2(H2O)2} (3), [Me3Sn(3,5-pdc)] n (4), [Ph3Sn(3,5-pdc)] n (5), [(PhCH2)3Sn(3,5-pdc)] n (6), [(Me3Sn)2(2,5-pdc)] n (7), [(Ph3Sn)2(2,5-pdc)] n (8) and {[(PhCH2)3Sn]2(2,5-pdc)} n (9) were synthesized by the reaction of trimethyltin(IV), triphenyltin(IV) or tribenzyltin(IV) chloride with 2,6(3,5 or 2,5)-H2pdc (pdc=pyridinedicarboxylate) when triethylamine was added. Complexes 1–9 have been characterized by elemental, IR, 1H, 13C and 119Sn NMR analyses. Among them complexes 1, 5 and 7 have also been characterized by X-ray crystallographic diffraction analyses. Complex 1 has a trinuclear structure and forms a 2D supramolecular structure due to the coordinated water molecules via hydrogen bonds to the pendant O atoms of the carboxyl groups and the N atoms derived of the pyridine ring. Complex 5 forms a 1D polymeric chain by the intermolecular Sn⋯N (N atom derived of pyridine ring) interactions. Complex 7 has a network structure where 2,5-pyridinedicarboxylate acts as a tetradentate ligand coordinated to trimethyltin(IV) ions. [Copyright &y& Elsevier]

Abstract: Two novel lanthanide coordination polymers [Sm(Hdipic)(dipic)(H2O)2·4H2O] n (1) (H2dipic=2,6-pyridinedicarboxylic acid) and [Dy(Hdinic)(dinic)(phen)(H2O)·H2O] n (2) (H2dinic=2,5-pyridinedicarboxylic acid) have been synthesized under hydrothermal condition and characterized by single-crystal X-ray diffraction. The results reveal that both of them form a chain-like one-dimensional structure. The photophysical properties for the two complexes have been also reported. Complex 1 shows the characteristic luminescence of central Sm3+ while complex 2 exhibits the particular emission ascribed H2dinic ligands, which suggest the different energy transfer process takes place. [Copyright &y& Elsevier]

On-column complexation of metal ions with 2,6-pyridinedicarboxylate (2,6-PDC) to form anionic complexes enabled their separation by capillary zone electrophoresis with direct UV detection at 214 nm. Nine metal ions, Cu2+, Zn2+, Ni2+, Cd2+, Mn2+, Pb2+, Fe3+, Al3+ and Ca2+, were determined in less than 7 min using10 mM 2,6-PDC solution containing 0.75 mM tetradecyltrimethylammonium bromide at pH 4.0. Satisfactory working ranges (20–300 μM), detection limits (3–10 μM) and good repeatability of the peak areas (RSD 2.1–4.2%, n=5) were obtained using hydrodynamic injection (30 s). The proposed method was used successfully for the determination of Mn2+, Fe3+, Al3+ and Ca2+ in groundwaters. [ABSTRACT FROM AUTHOR]

Three novel lanthanide upconverting materials [LN(2,5-HPA)(2,5-PA)] n (LN ​= ​Sm, 1 ; Dy, 2 ; Ho, 3 ; 2,5-H 2 PA ​= ​2,5-pyridinedicarboxylic acid) have been synthesized through hydrothermal reactions and structurally characterized by single crystal X-ray diffraction technique. These materials are crystallographically isostructural and are characteristic of three-dimensional (3-D) frameworks. The photoluminescence measurements with solid-state samples reveal that compounds 1 – 3 exhibit upconversion photoluminescence emissions in red, yellow and green region, respectively. The photoluminescence emission bands could be assigned to the characteristic emission of the 4 f electrons intrashell transition of the 4 G 5/2 ​→ ​6 H 7/2 , 4 G 5/2 ​→ ​6 H 9/2 of the Sm3+ ions in 1 , 4 F 9/2 ​→ ​6 H 17/2 , 4 F 9/2 ​→ ​6 H 15/2 , 4 F 9/2 ​→ ​6 H 13/2 of the Dy3+ ions in 2 , and 5 G 6 → 5 I 8 , 5 S 2 → 5 I 8 of the Ho3+ ions in 3. An energy transfer mechanism is explained by the energy level diagrams of the lanthanide ions and the 2,5-H 2 PA ligand. Solid-state UV/Vis diffuse reflectance spectra reveal that they are potential wide optical band gap semiconductors with the band gaps being of 3.73, 3.56 and 3.45 ​eV for 1 – 3 , respectively. TG curves reveal that all of them are very thermal stable with the onset temperature being of 219 ​°C–322 ​°C. The photoluminescence quantum yields of compounds 1 – 3 were determined to be 14.1%, 18.3% and 19.6%, respectively. Three novel lanthanide upconverting materials were reported. They feature thermally stable 3-D frameworks. They exhibit upconversion photoluminescence emissions and remarkable CIE chromaticity coordinates. Energy transfer mechanism is explained. Their optical band gaps are 3.73, 3.56 and 3.45 ​eV. Image 1 • It reports three thermally stable lanthanide upconverting materials. • The emission bands result from the characteristic emissions of the lanthanide ions. • They have remarkable CIE chromaticity coordinates. • Energy transfer mechanism is explained by the energy level diagram. • They have wide optical band gaps. [ABSTRACT FROM AUTHOR]