Synthesis and pharmacological characterisation of arctigenin analogues as antagonists of AMPA and kainate receptors.

(-)-Arctigenin and a series of new analogues have been synthesised and then tested for their potential as AMPA and kainate receptor antagonists of human homomeric GluA1 and GluK2 receptors expressed in HEK293 cells using a Ca influx assay. In general, these compounds showed antagonist activity at both receptors with greater activity evident at AMPARs. Schild analysis indicates that a spirocyclic analogue 6c acts as a non-competitive antagonist.

Filling a Niche in "Ligand Space" with Bulky, Electron-Poor Phosphorus(III) Alkoxides.

The chemistry of phosphorus(III) ligands, which are of key importance in coordination chemistry, organometallic chemistry and catalysis, is dominated by relatively electron-rich species. Many of the electron-poor P ligands that are readily available have relatively small steric profiles. As such, there is a significant gap in "ligand space" where more sterically bulky, electron-poor P ligands are needed.

Registry Assessment of Peripheral Interventional Devices (RAPID): Registry assessment of peripheral interventional devices core data elements.

Objective: The current state of evaluating patients with peripheral artery disease and more specifically of evaluating medical devices used for peripheral vascular intervention (PVI) remains challenging because of the heterogeneity of the disease process, the multiple physician specialties that perform PVI, the multitude of devices available to treat peripheral artery disease, and the lack of consensus about the best treatment approaches. Because PVI core data elements are not standardized across clinical care, clinical trials, and registries, aggregation of data across different data sources and physician specialties is currently not feasible.

Methods: Under the auspices of the U.

Registry Assessment of Peripheral Interventional Devices (RAPID) - Registry Assessment of Peripheral Interventional Devices Core Data Elements.

Background: The current state of evaluating patients with peripheral artery disease and more specifically of evaluating medical devices used for peripheral vascular intervention (PVI) remains challenging because of the heterogeneity of the disease process, the multiple physician specialties that perform PVI, the multitude of devices available to treat peripheral artery disease, and the lack of consensus about the best treatment approaches. Because PVI core data elements are not standardized across clinical care, clinical trials, and registries, aggregation of data across different data sources and physician specialties is currently not feasible.Methods and Results:Under the auspices of the U.

Structure of Amido Pyridinium Betaines: Persistent Intermolecular C-H⋅⋅⋅N Hydrogen Bonding in Solution.

A hydrogen bond of the type C-H⋅⋅⋅X (X=O or N) is known to influence the structure and function of chemical and biological systems in solution. C-H⋅⋅⋅O hydrogen bonding in solution has been extensively studied, both experimentally and computationally, whereas the equivalent thermodynamic parameters have not been enumerated experimentally for C-H⋅⋅⋅N hydrogen bonds. This is, in part, due to the lack of systems that exhibit persistent C-H⋅⋅⋅N hydrogen bonds in solution.

Halogen-bonded liquid crystals of 4-alkoxystilbazoles with molecular iodine: a very short halogen bond and unusual mesophase stability.

Complexes of molecular iodine with alkoxystilbazoles are liquid crystals with unusually high mesophase stability, predicated on an intermolecular I···I contact. Attempts to prepare analogous complexes with bromine led to an unexpected electrophilic substitution product.

cis-1,3,5-Triaminocyclohexane as a facially capping ligand for ruthenium(II).

Reaction of cis-[RuCl2(DMSO-S)3(DMSO-O)] with cis-1,3,5-triaminocyclohexane (tach) results in the formation of [RuCl(tach)(DMSO-S)2]Cl, a valuable precursor for a wide range of other tach-containing Ru complexes. Reaction of [RuCl(tach)(DMSO-S)2]Cl with the chelating nitrogen-based ligands (N-N = bipyridine, phenanthroline, and ethylenediamine) affords [Ru(N-N)(DMSO-S)2(tach)][Cl]2. A similar reaction between [RuCl(tach)(DMSO-S)]Cl with the chelating phosphorus-based ligands (P-P = dppm, dppe, dppp, dppb, dppv, and dppben) leads to the formation of [RuCl(P-P)(tach)]Cl.

Ruthenium-mediated C-H functionalization of pyridine: the role of vinylidene and pyridylidene ligands.

A combined experimental and theoretical study has demonstrated that [Ru(η(5)-C(5)H(5))(py)(2)(PPh(3))](+) is a key intermediate, and active catalyst for, the formation of 2-substituted E-styrylpyridines from pyridine and terminal alkynes HC≡CR (R = Ph, C(6)H(4)-4-CF(3)) in a 100% atom efficient manner under mild conditions. A catalyst deactivation pathway involving formation of the pyridylidene-containing complex [Ru(η(5)-C(5)H(5))(κ(3)-C(3)-C(5)H(4)NCH═CHR)(PPh(3))](+) and subsequently a 1-ruthanaindolizine complex has been identified. Mechanistic studies using (13)C- and D-labeling and DFT calculations suggest that a vinylidene-containing intermediate [Ru(η(5)-C(5)H(5))(py)(═C═CHR)(PPh(3))](+) is formed, which can then proceed to the pyridylidene-containing deactivation product or the desired product depending on the reaction conditions.

Charged behaviour from neutral ligands: synthesis and properties of N-heterocyclic pseudo-amides.

Deprotonation of the 1-isopropyl-3-(phenylamino)pyridin-1-ium iodide gives the corresponding neutral betaine, which is formalised as a pyridinium-amido ligand when coordinated to a metal. Spectroscopic, structural and theoretical methods have been used to investigate the metal-ligand bonding, ligand dynamics and electron distribution. Collectively, the data show that the ligand can be characterised as a pseudo-amide and is a strong donor akin to alkyl phosphines and N-heterocyclic carbenes.

Selective photochemistry at stereogenic metal and ligand centers of cis-[Ru(diphosphine)2(H)2]: preparative, NMR, solid state, and laser flash studies.

Three ruthenium complexes Λ-[cis-Ru((R,R)-Me-BPE)(2)(H)(2)] Λ-R,R-Ru1H(2), Δ-[cis-Ru((S,S)-Me-DuPHOS)(2)(H)(2)] Δ-S,S-Ru2H(2), and Λ-[cis-Ru((R,R)-Me-DuPHOS)(2)(H)(2)] Λ-R,R-Ru2H(2) (1 = (Me-BPE)(2), 2 = (Me-DuPHOS)(2)) were characterized by multinuclear NMR and CD spectroscopy in solution and by X-ray crystallography. The chiral ligands allow the full control of stereochemistry and enable mechanistic studies not otherwise available. Oxidative addition of E-H bonds (E = H, B, Si, C) was studied by steady state and laser flash photolysis in the presence of substrates.

β-Carboline (norharman).

The structure of β-carboline, also called norharman (systematic name: 9H-pyrido[3,4-b]indole), C(11)H(8)N(2), has been determined at 110 K. Norharman is prevalent in the environment and the human body and is of wide biological interest. The structure exhibits intermolecular N-H···N hydrogen bonding, which results in a one-dimensional herringbone motif.

Tetra-μ2-acetato-diacetatodi-μ3-hydroxido-tetrakis[piperidinecopper(II)] dihydrate.

The title complex, [Cu(4)(C(2)H(3)O(2))(6)(OH)(2)(C(5)H(11)N)(4)]·2H(2)O, possesses an unusual inversion-symmetric tetranuclear copper framework, with each Cu(II) atom displaying a square-pyramidal geometry and one additional long Cu···O contact. The four piperidine ligands are terminal, one at each Cu(II) atom, and the two hydroxide ligands are triply bridging. The six acetate ligands exhibit two distinct coordination modes, namely as two monodentate acetates and four bridging acetates that bridge the two inequivalent copper centres.

Pd-catalysed regioselective C-H functionalisation of 2-pyrones.

A new synthetic methodology for the catalytic C-H functionalisation of 2-pyrones is described which proceeds regioselectively at the C3 position, mirroring the observed regioselectivity in 6π-electrocyclisation/oxidative aromatisation reactions of related compounds. Insight into the reaction mechanism is provided, with support for a neutral palladium(II) pathway. Cationic palladium(II) complexes possessing 2-pyrones are unstable and readily undergo Pd(II)→P transfer at ambient temperature resulting in phosphonium salt formation (and Pd(0)L(n) species).

Synthesis, coordination chemistry and bonding of strong N-donor ligands incorporating the 1H-pyridin-(2E)-ylidene (PYE) motif.

A range of N-donor ligands based on the 1H-pyridin-(2E)-ylidene (PYE) motif have been prepared, including achiral and chiral examples. The ligands incorporate one to three PYE groups that coordinate to a metal through the exocyclic nitrogen atom of each PYE moiety, and the resulting metal complexes have been characterised by methods including single-crystal X-ray diffraction and NMR spectroscopy to examine metal-ligand bonding and ligand dynamics. Upon coordination of a PYE ligand to a proton or metal-complex fragment, the solid-state structures, NMR spectroscopy and DFT studies indicate that charge redistribution occurs within the PYE heterocyclic ring to give a contribution from a pyridinium-amido-type resonance structure.

Ion-tagged pi-acidic alkene ligands promote Pd-catalysed allyl-aryl couplings in an ionic liquid.

Ionic pi-acidic alkene ligands based on chalcone and benzylidene acetone frameworks have been "doped" into ionic liquids to provide functional reaction media for Pd-catalysed cross-couplings of a cyclohexenyl carbonate with aryl siloxanes that allow simple product isolation, free from Pd (<50 ppm) and ligand contamination.

Diversity and design of metal-based carbon monoxide-releasing molecules (CO-RMs) in aqueous systems: revealing the essential trends.

The CO-releasing ability of a diverse library of primary metal carbonyl complexes has been assessed using a deoxymyoglobin-carbonmonoxymyglobin assay. A wide spectrum of rates for the CO-release process was observed in aqueous systems. For octahedral d(6) complexes, the rate was found to decrease in the sequence FeI(2)(CO)(4) > [NEt(4)][V(CO)(6)] > MnBr(CO)(5) > Cr(CO)(6) implying that CO-release is not controlled by the metal-carbon bond strengths.

Pd(0)/Cu(I)-mediated direct arylation of 2'-deoxyadenosines: mechanistic role of Cu(I) and reactivity comparisons with related purine nucleosides.

Pd/Cu-mediated direct arylation of 2'-deoxyadenosine with various aryl iodides provides 8-arylated 2'-deoxyadenosine derivatives in good yields. Following significant reaction optimization, it has been determined that a substoichiometric quantity of piperidine (secondary amine) in combination with cesium carbonate is necessary for effective direct arylation. The general synthetic protocol allows lower temperature direct arylations, which minimizes deglycosylation.