Low-Dimensional Architectures in Isomeric cis-PtCl2{Ph2PCH2N(Ar)CH2PPh2} Complexes Using Regioselective-N(Aryl)-Group Manipulation.

The solid-state behaviour of two series of isomeric, phenol-substituted, aminomethylphosphines, as the free ligands and bound to PtII, have been extensively studied using single crystal X-ray crystallography. In the first library, isomeric diphosphines of the type Ph2PCH2N(Ar)CH2PPh2 [1a-e; Ar = C6H3(Me)(OH)] and, in the second library, amide-functionalised, isomeric ligands Ph2PCH2N{CH2C(O)NH(Ar)}CH2PPh2 [2a-e; Ar = C6H3(Me)(OH)], were synthesised by reaction of Ph2PCH2OH and the appropriate amine in CH3OH, and isolated as colourless solids or oils in good yield. The non-methyl, substituted diphosphines Ph2PCH2N{CH2C(O)NH(Ar)}CH2PPh2 [2f, Ar = 3-C6H4(OH); 2g, Ar = 4-C6H4(OH)] and Ph2PCH2N(Ar)CH2PPh2 [3, Ar = 3-C6H4(OH)] were also prepared for comparative purposes. Reactions of 1a-e, 2a-g, or 3 with PtCl2(η4-cod) afforded the corresponding square-planar complexes 4a-e, 5a-g, and 6 in good to high isolated yields. All new compounds were characterised using a range of spectroscopic (1H, 31P{1H}, FT-IR) and analytical techniques. Single crystal X-ray structures have been determined for 1a, 1b∙CH3OH, 2f∙CH3OH, 2g, 3, 4b∙(CH3)2SO, 4c∙CHCl3, 4d∙½Et2O, 4e∙½CHCl3∙½CH3OH, 5a∙½Et2O, 5b, 5c∙»H2O, 5d∙Et2O, and 6∙(CH3)2SO. The free phenolic group in 1b∙CH3OH, 2f∙CH3OH,2g, 4b∙(CH3)2SO, 5a∙½Et2O, 5c∙»H2O, and 6∙(CH3)2SO exhibits various intra- or intermolecular O-H∙∙∙X (X = O, N, P, Cl) hydrogen contacts leading to different packing arrangements.

Synthesis and evaluation of a pentafluorobenzamide stationary phase for HPLC separations in the reversed phase and hydrophilic interaction modes.

A pentafluorobenzamide stationary phase was synthesized by an easy method with no intermediate purification steps. Physicochemical characterization (elemental analysis, fourier transform infrared spectroscopy, 29 Si and 13 C nuclear magnetic resonance spectroscopy) confirmed the presence of pentafluorobenzamide functionalization on the surface of the silica particles. The pentafluorobenzamide stationary phase proved to be quite versatile as it can be used in two different modes in liquid chromatography: reversed phase and hydrophilic interaction liquid chromatography. Chromatographic characterizations in both modes confirmed the multiple interactions established by the new stationary phase, such as hydrogen bonding and π-π and ion-exchange interactions. The pentafluorobenzamide stationary phase was successfully employed for the separation of nucleosides and antihypertensive drugs under hydrophilic interaction liquid chromatography conditions, as well as pesticides and benzodiazepine using reversed phase conditions. The stationary phase showed significant potential when compared with commercial columns.

Coated Cotton Fabrics with Antibacterial and Anti-Inflammatory Silica Nanoparticles for Improving Wound Healing.

Herein, we report the preparation of bifunctional silica nanoparticles by covalent attachment of both an anti-inflammatory drug (ibuprofen) and an antibiotic (levofloxacin or norfloxacin) through amide groups. We also describe the coating of cotton fabrics with silica nanoparticles containing both ibuprofen and norfloxacin moieties linked by amide groups by using a one-step coating procedure under ultrasonic conditions. The functionalized nanoparticles and cotton fabrics have been characterized using spectroscopic and microscopic techniques. The functionalized nanoparticles and textiles have been treated with model proteases for the in situ release of the drugs by the amide bond enzymatic cleavage. Topical dermal applications in medical bandages are expected, which favor wound healing.

Removal of nickel and copper ions in strongly acidic conditions by in-situ formed amyloid fibrils.

The research investigated a novel strategy that can synchronously remove Ni2+ and Cu2+ by synthesizing amyloid fibrils under harsh conditions. The adsorption capacity of Ni2+ and Cu2+ increased by 18.5% and 34.1% respectively in the in-situ scenario as compared to that Ni2+ and Cu2+ were introduced after amyloid fibrils preparation, meantime, it avoids the generation of acidic waste liquid in the process of preparing amyloid fibrils. The adsorption behaviors of Ni2+ and Cu2+ can be well described by the pseudo-second-order kinetic model and Langmuir isotherm. The functional groups of amide, hydroxyl, and carboxyl played determining roles in the adsorption process. Moreover, when the amyloid fibrils were prepared in the presence of Ni2+ and Cu2+, i.e., the in-situ adsorption scenario, metal ions tended to occupy the functional sites, inhibit protein aggregation, and affect long amyloid fibrils synthesis accordingly. Metal ion-binding site prediction server was used to predict the binding sites of metal ions towards the protein sequence within amyloid fibrils, and the metal ion was observed to preferentially bind to a particular residue such as glutamic acid, cysteine, and serine. The amyloid fibrils be potentially valuable for the removal of heavy metals in strongly acidic wastewater such as acidic mining drainage.

Improving Electrochemical Performance and Safety of Lithium-Sulfur Batteries by a "Bulletproof Vest".

In the field of high-density energy storage, lithium-sulfur (Li-S) batteries have attracted more and more attention because of their high specific capacity and affordable cost. However, their actual implementation is hindered by the dissolution of polysulfides and severe safety concerns caused by flammable electrolytes. Herein, we report the preparation of an interlayer that can effectively suppress polysulfide shuttling and increase the working temperature range. In this work, polyamide nanofibers (ANFs) are used as the substrate material to prepare the Ni(OH)2@ANFs-Ni (NAFN) film that works as the interlayer on the "outside" of the cathode in situ. The experimental results show that Li-S batteries containing NAFN as the interlayer can achieve excellent outstanding stability in a long cycle life. After 800 cycles at 1 C, the capacity remains at 482 mA h/g, with a decay rate of 0.047%. At high temperature (60 °C), after 500 cycles at 1 C, its capacity is 622 mA h/g with a decay rate of 0.079%. Therefore, the flexible design of the NAFN interlayer provides the growth of high-performance Li-S batteries with novel insights. The ultrathin, microporous structure of the interlayer tightly wraps the cathode material, just like the addition of a "bulletproof vest" inside the Li-S batteries. The plentiful amide functional groups of the "bulletproof vest" enable the strong complexation reaction with polysulfides to suppress the polysulfides' shuttling effect and ensure a facile Li+ transfer. At the same time, the nickel hydroxide is able to accelerate the redox kinetics via reaction with polysulfides to produce the intermediate thiosulfate groups. Also, the ANFs as the heat-resistant material ensure the stability of the batteries at high temperatures.

Fluorescence quenching, structural and unfolding studies of a purified cysteine protease, ZCPG from Zingiber montanum rhizome.

A first attempt was made to study the fluorescence quenching, structure and unfolding nature of the purified Zingiber montanum (J.Koenig) Link ex A.Dietr. cysteine protease glycoprotein (ZCPG). ATR-IR spectra showed the presences of amide groups along with carbohydrate stretch indicating the glycoprotein nature. UV-vis spectra determined the presences of peptide groups and aromatic sidechains of tyrosine, tryptophan and phenylalanine. Far UV-Circular Dichroism spectrum revealed that the secondary structure consists of 47.6% α-helix, 14.1% ß-sheet, 16.1% ß-turn, and 22.2% random coil. CD signals revealed pronounced structural stability until 70°C followed by a significant variation in the secondary structure content in the transition temperature between 80-90°C. ZCPG retained most of its secondary structure in the pH range of 3.0-10.0. The extrinsic study shows that at pH 2.0, ZCPG revealed characteristics of a molten globule-like state exhibiting strong ANS binding. The effect of GdnHCl on ZCPG evaluated by far-CD emission maximum and fluorescence emission revealed that the unfolding was incomplete determining the stability of the protein. The microenvironment of the tryptophan residues indicated the presence of relatively exposed single tryptophan residue (per monomer) with positively charged side chains.

Crystal structure of N,N'-(1,2-phenyl-ene)bis-(2-chloro-acetamide).

In the title compound, C10H10Cl2N2O2, the secondary amide groups are differently twisted relative to the benzene ring, with dihedral angles between the respective planes of 21.03 (2) and 81.22 (2)°. In the crystal, the mol-ecules are connected by N-H⋯O and C-H⋯O hydrogen bonds, forming a two-dimensional polymeric network parallel to (001). One of the amide carbonyl O atoms accepts two H atoms in N-H⋯O and C-H⋯O inter-actions, forming an R 2 (2)(6) ring motif.