Ruthenium complexes with triazenide ligands bearing an N-heterocyclic moiety, and their catalytic properties in the reduction of nitroarenes.

A series of ruthenium complexes of formulae [RuCl(triazenide)(-cymene)] have been synthesized using as ligand a triazenide monofunctionalized with an N-heterocyclic moiety. Nuclear magnetic resonance, high resolution mass spectrometry and X-ray diffraction were used to characterize the triazenide ligands and their complexes. In addition, these ruthenium complexes catalyzed the reduction of nitrobenzene to aniline in the presence of sodium borohydride and ethanol as solvent at room temperature.

Study of electrospun nanofibers loaded with Ru(ii) phenanthroline complexes as a potential material for use in dye-sensitized solar cells (DSSCs).

Dye-sensitized solar cells (DSSCs) are an increasingly attractive alternative energy source because of their low cost. Therefore, researchers have intensified efforts over the past decade to increase their energy conversion efficiency by employing new materials in each DSSC component. The present research focuses on synthesizing electrospun nanofibers as a potential new material as a counter electrode in DSSCs.

Bacterial Biofilm Formation Using PCL/Curcumin Electrospun Fibers and Its Potential Use for Biotechnological Applications.

Electrospun nanofibers are used for many applications due to their large surface area, mechanical properties, and bioactivity. Bacterial biofilms are the cause of numerous problems in biomedical devices and in the food industry. On the other hand, these bacterial biofilms can produce interesting metabolites.

Novel Linezolid analogues with antiparasitic activity against Hymenolepis nana.

The stereoselective synthesis and anti- Hymenolepis nana activity of six Linezolid-type compounds, obtained by chemical modification of l-Alanine, are reported in this work. The synthetic strategy was to prepare diasteromeric N,N-dibenzylamino oxazolidinones 1 and 2, and coupling with 4-(4-bromophenyl)morpholine (3) to obtain N,N-dibenzylamino Linezolid analogues 4 and 5. A hydrogenolysis reaction over 4 and 5 resulted in amino-free Linezolid analogues 6 and 7, which were acetylated to reach diasteromeric Linezolid analogues 8 and 9.

Bioguided isolation of -malonyl-(+)tryptophan from the fruit of (Roxb.) Benth. that showed high activity against .

is distributed in America and Asia where is widely used in traditional medicine. This study describes the bioguided fractionation of the methanol extract (ME) obtained from the fruit that showed activity against ; assay was used to determine toxicity; and the purified compound was computationally analysed to obtain its absorption-distribution-metabolism-excretion-and-toxicity properties (ADMET). The ME and its fractions were more active than praziquantel (PZQ), and the purified compound was characterized as -malonyl-(+)tryptophan (NMT).

Anthocyanins of Pithecellobium dulce (Roxb.) Benth. Fruit Associated with High Antioxidant and α-Glucosidase Inhibitory Activities.

Red arils of Pithecellobium dulce fruit, commonly known as guamuchil, show high antioxidant (AOx) and α-glucosidase inhibitory (IαG) activities, which have been mainly associated with the content of unknown anthocyanins. In this study, the AOx (i.e.

Synthesis, crystal structure, DFT studies and photophysical properties of a copper(I)-triphenylphosphane complex based on trans-(±)-2,4,5-tris(pyridin-2-yl)-2-imidazoline.

The possibility of using less expensive and nontoxic metals, such as copper, as substitutes for more expensive heavy metals in the synthesis of new transition-metal complexes to be used as sensitizers in dye-sensitized solar cells (DSSCs) has stimulated research in this field. The novel photoluminescent copper(I) complex bis(triphenylphosphane-κP)[trans-(±)-2,4,5-tris(pyridin-2-yl)-2-imidazoline-κN,N]copper(I) hexafluorophosphate, [Cu(CHN)(CHP)]PF, has been successfully synthesized and characterized by IR and H NMR spectroscopy, as well as by single-crystal X-ray diffraction and thermogravimetric analysis. The complex showed interesting photophysical properties, which were studied experimentally in solution and in the solid state by UV-Vis and fluorescence spectroscopy.

Evolution of iridium-based molecular catalysts during water oxidation with ceric ammonium nitrate.

Organometallic iridium complexes have been reported as water oxidation catalysts (WOCs) in the presence of ceric ammonium nitrate (CAN). One challenge for all WOCs regardless of the metal used is stability. Here we provide evidence for extensive modification of many Ir-based WOCs even after exposure to only 5 or 15 equiv of Ce(IV) (whereas typically 100-10000 equiv are employed during WOC testing).

Imidazol-2-yl complexes of Cp*Ir as bifunctional ambident reactants.

Loss of chloride ion from imidazol-2-yl complex 4a activates the H-H bond of dihydrogen or the C-H bond of acetylene, forming an Ir(III) N-heterocyclic carbene (NHC) complex (3b or 9). Deprotonation of Ir(III) hydride 4b gives one new species, formulated as Ir(I) carbene complex 5. Protonation or alkylation of 5 occurs at the metal, returning the Ir(III) core of 6a,b.

Finding the proton in a key intermediate of anti-Markovnikov alkyne hydration by a bifunctional catalyst.

The secondary structure of a bifunctional catalyst positions a crucial reactive proton in the final intermediate of anti-Markovnikov alkyne hydration to give an aldehyde. NMR coupling and isotopic labeling studies elucidate the location of this proton and its involvement in hydrogen bonding.

Hydrogen-bond acceptance of bifunctional ligands in an alkyne-metal pi complex.

Experiment and theory have been used to study reactive alkyne pi complexes, intermediates in anti-Markovnikov alkyne hydration by CpRu bis(phosphine) catalysts with heterocyclic substituents. Each heterocycle accepts a hydrogen bond from an acetylene C-H, as revealed by NMR coupling constants between alkyne 13C and 1H nuclei as well as between alkyne 13C and pyridine 15N (2hJCN). Moreover, further alkyne transformations occur at temperatures from 50 to 90 degrees C below what is needed to convert a control compound without the heterocycles.