Tetra-μ-aqua-octaaqua­bis(μ-4-chloro­pyridine-2,6-dicarboxyl­ato)bis­(4-chloro­pyridine-2,6-dicarboxyl­ato)tri­cobalt(II)disodium(I) bis­[triaqua­bis(4-chloro­pyridine-2,6-dicarboxyl­ato)cobalt(II)] hexa­hydrate

The title compound, [Co3Na2(C7H2ClNO4)4(H2O)12][Co(C7H2ClNO4)(H2O)3]2·6H2O, consists of a centrosymmetric dimer of [CoII(dipicCl)2]2− complex dianions [dipicCl is 4-chloro­pyridine-2,6-dicarboxyl­ate] bridged by an [Na2CoII(H2O)12]4+ tetra­cationic cluster, two independent [Co(dipicCl)(H2O)3] complexes, and six water mol­ecules of crystallization. The metals are all six-coordinate with distorted octahedral geometries. The [CoII(dipicCl)(H2O)3] complexes are neutral, with one tridentate ligand and three water molecules. The [CoII(dipicCl)2]2− complexes each have two tridentate ligands. The [Na2CoII(H2O)12]4+ cluster has a central CoII ion which is coordinated to six water molecules and lies on a crystallographic inversion center. Four of the water molecules bridge to two sodium ions, each of which have three other water molecules coordinated along with an O atom from the [CoII(dipicCl)2]2− complex. In the crystal structure, the various units are linked by O—H⋯O hydrogen bonds, forming a three-dimensional network. Two water molecules are disordered equally over two positions

CCDC 706305: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.,Related Article: V.H.Rambaran, S.Balof, L.Moody, D.VanDerveer, A.A.Holden|2009|CrystEngComm|11|580|doi:10.1039/b822030

A New and Efficient Synthetic Route for the Synthesis of 3,6-Dimethylpyrazine-2,5-Dicarboxylic Acid Hydrate: Molecular Structure and Unique Supramolecular Interactions

The regioselective oxidation of 2,3,5,6,-tetramethyl pyrazine by selenium dioxide and silver nitrate resulted in the production of, 3,6-dimethylpyrazine-2,5-dicarboxylic acid hydrate in high yields. Its crystal structure, which is reported for the very first time, consists of a unique infinite three-dimensional lattice of hydrogen-bonded acid and water molecules

Tetra-\u3ci\u3eμ\u3c/i\u3e-aqua-octaaquabis(\u3ci\u3eμ\u3c/i\u3e-4-chloropyridine-2,6-dicarboxylato(bis(4-chloro-pyridine-2,6-dicarboxylato)tricobalt(II)-disodium(I) Bis[triaquabis(4-chloro-pyridine-2,6-dicarboxylato)cobalt(II)] Hexahydrate

The title compound, [Co3Na2(C72ClNO4)4(H2O)12][Co(C7H2ClNO4(H2O)3]2·6H2O, consists of a centrosymmetric dimer of [CoII(dipicCl)2]2- complex dianions [dipicCl is 4-chloro­pyridine-2,6-dicarboxyl­ate] bridged by an [Na2CoII(H2O)12]4+ tetra­cationic cluster, two independent [Co(dipicCl)(H2O)3] complexes, and six water mol­ecules of crystallization. The metals are all six-coordinate with distorted octahedral geometries. The [CoII(dipicCl)(H2O)3] complexes are neutral, with one tridentate ligand and three water molecules. The [CoII(dipicCl)2]2- complexes each have two tridentate ligands. The [Na2CoII(H2O)12]4+ cluster has a central CoII ion which is coordinated to six water molecules and lies on a crystallographic inversion center. Four of the water molecules bridge to two sodium ions, each of which have three other water molecules coordinated along with an O atom from the [CoII(dipicCl)2]2- complex. In the crystal structure, the various units are linked by O-H···O hydrogen bonds, forming a three-dimensional network. Two water molecules are disordered equally over two positions

Expanding Opportunities for Functional Surfaces: New Self-Degreasing Laminates

A properly designed and formulated lipolytic enzyme additive into laminates provides a self-degreasing material that can be prepared using conventional, established production equipment. Laminates were prepared by first infusing a resin formulation into kraft paper and then conditioning the resin in a forced air oven. Manual pressing of samples between aluminum panels was carried out at commercially-acceptable pressures and temperatures. The activity of the enzyme was then determined by following the hydrolysis of the oil-analog p-nitrophenyl acetate using a colorimetric method. Initial results indicated that the enzyme retained complete activity in the resin alone up to 105°C for two hours. When properly conditioned, the lipolytic enzyme not only remained catalytically active after being pressed under manufacturing conditions, but also remained stable in pressed composites stored at room temperature

CCDC 674276: Experimental Crystal Structure Determination

Related Article: L.Moody, S.Balof, S.Smith, V.H.Rambaran, D.VanDerveer, A.A.Holder|2008|Acta Crystallogr.,Sect.E:Struct.Rep.Online|64|m262|doi:10.1107/S1600536807067141,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures

Inhibition of Aβ42 Peptide Aggregation by a Binuclear Ruthenium(II)−Platinum(II) Complex: Potential for Multimetal Organometallics as Anti-amyloid Agents

Design of inhibitors for amyloid-β (Aβ) peptide aggregation has been widely investigated over the years toward developing viable therapeutic agents for Alzheimer’s disease (AD). The biggest challenge seems to be inhibiting Aβ aggregation at the early stages possibly at the monomeric level, because oligomers are known to be neurotoxic. In this regard, exploiting the metal-chelating property of Aβ to generate molecules that can overcome this impediment presents some promise. Recently, one such metal complex containing PtII ([Pt(BPS)Cl2]) was reported to effectively inhibit Aβ42 aggregation and toxicity (Barnham, et al. (2008) Proc. Natl. Acad. Sci. U.S.A.105, 6813). This complex was able bind to Aβ42 at the N-terminal part of the peptide and triggered a conformational change resulting in effective inhibition. In the current report, we have generated a mixed-binuclear metal complex containing PtII and RuII metal centers that inhibited Aβ42 aggregation at an early stage and seemed to have different modes of interaction than the previously reported PtII complex, suggesting an important role of the second metal center. This ‘proof-of-concept’ compound will help in developing more effective molecules against Aβ aggregation by modifying the two metal centers as well as their bridging ligands, which will open doors to new rationale for Aβ inhibition

CCDC 908445: Experimental Crystal Structure Determination

Related Article: Varma H. Rambaran, Travis R. Erves, Kristy Grover, Shawna Balof, LaMaryet V. Moody, Stuart E. Ramsdale, Luke A. Seymour, Don VanDerveer, Donald M. Cropek, Ralph T. Weber, Alvin A. Holder|2013|J.Chem.Cryst.|43|509|doi:10.1007/s10870-013-0437-7,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures

CCDC 908444: Experimental Crystal Structure Determination

Related Article: Varma H. Rambaran, Travis R. Erves, Kristy Grover, Shawna Balof, LaMaryet V. Moody, Stuart E. Ramsdale, Luke A. Seymour, Don VanDerveer, Donald M. Cropek, Ralph T. Weber, Alvin A. Holder|2013|J.Chem.Cryst.|43|509|doi:10.1007/s10870-013-0437-7,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures

A Comparison of the Self Assembled Frameworks of Three Cobalt(II) Coordination Compounds Bearing Dipicolinic Acid and Chelidamic Acid Ligands

A comparison of the self assembled lattice structures of unpublished coordination compound, [Co(dipic-OH)(OH2)3]·1.5H2O (I) (where dipic-OH = 4-hydroxypyridine-2,6-dicarboxylate anion) and two novel cobalt(II)-containing coordination compounds, [Co(dipic)(pyz)(OH2)]·0.25DMSO (II) (where dipic = dipicolinate anion and pyz = 2-(H-pyrazol-3-yl)-pyridine) and [Co(dipic-OH)(pyz)(OH2)]·H2O (III), have revealed remarkable distinctions in the hierarchy of their respective structures. The three dimensional (3-D) layered scaffold of compound I and the “zigzag” motifs of compounds II and III were found to have been created via unique hydrogen bonding patterns. Interestingly, compound III displayed a secondary 3-D channel framework, which was made possible by π–π stacking interactions. Spectroscopic studies yielded results that were consistent with the predicted behaviors of the various species of substituted ligands. X-ray crystallography revealed that compound I crystallized in the monoclinic space group C2/c with a = 14.734(3) Å, b = 6.8664(14) Å, c = 22.411(5) Å, α = 90°, β = 90.097(7)°, γ = 90°, V = 2267.4(8) Å3, Z = 8; compound II crystallized in the monoclinic space group P21/n with a = 11.621(3) Å, b = 12.391(3) Å, c = 12.537(4) Å, α = 90°, β = 102.148(11)°, γ = 90°, V = 1764.8(8) Å3, Z = 4; and compound III crystallized in the orthorhombic space group Pccn with a = 21.899(2) Å, b = 10.8845(11) Å, c = 15.7093(13) Å, α = 90°, β = 90°, γ = 90°, V = 3744.4(6) Å3, Z = 8