Deciphering Electrocatalytic Hydrogen Production in Water Through a Bioinspired Water-Stable Copper(II) Complex Adorned with (NS)-Donor Sites.

Electrocatalytic hydrogen production stands as a pivotal cornerstone in ushering the revolutionary era of the hydrogen economy. With a keen focus on emulating the significance of hydrogenase-like active sites in sustainable H generation, a meticulously designed and water-stable copper(II) complex, [Cl-Cu-L]ClO, featuring the N,S-type ligand, L (2,2'-((butane-2,3-diylbis(sulfanediyl))bis(methylene))dipyridine), has been crafted and assessed for its prowess in electrocatalytic H production in water, leveraging acetic acid as a proton source. The molecular catalyst, adopting a square pyramidal coordination geometry, undergoes -Cl substitution by HO during electrochemical conditions yielding [HO-Cu-L] as the true catalyst, showcases outstanding activity in electrochemical proton reduction in acidic water, achieving an impressive rate of 241.

Upgrading of nitrate to hydrazine through cascading electrocatalytic ammonia production with controllable N-N coupling.

Nitrogen oxides (NO) play important roles in the nitrogen cycle system and serve as renewable nitrogen sources for the synthesis of value-added chemicals driven by clean electricity. However, it is challenging to achieve selective conversion of NO to multi-nitrogen products (e.g.

Asymmetric Synthesis of Benzofuranones with a C3 Quaternary Center via an Addition/Cyclization Cascade Using Noncovalent N-Heterocyclic Carbene Catalysis.

An asymmetric addition/cyclization cascade of amidoesters and iminoquinones is developed using noncovalent N-heterocyclic carbene (NHC) catalysis. The process enables access to various functionalized benzofuranones with an all-carbon quaternary stereocenter with high yields and ee values. The reaction displays a broad substrate scope.

Histidine-bridged cyclic peptide natural products: isolation, biosynthesis and synthetic studies.

The histidine bridge is a rare and often overlooked structural motif in macrocyclic peptide natural products, yet there are several examples in nature of cyclic peptides bearing this moiety that exhibit potent biological activity. These interesting compounds have been the focus of several studies reporting their isolation, biosynthesis and chemical synthesis over the last four decades. This review summarises the findings on the structure, biological activity and, where possible, proposed biosynthesis and progress towards the synthesis of histidine-bridged cyclic peptides.

Structural Effect of N-7 Alkylation in 6-Chloropurine on Cu (II) Binding: Effect of Anions and Magnetic Studies.

This study investigates the anion-directed assembly of discrete copper (II) complexes. The ligands of choice are two N7-alkyl-purine-based neutral ligands. These ligands facilitate the exclusive coordination through the N3 and N9 positions, preventing polymeric chain formation.

DFT mechanistic insights into the formation of the metal-dioxygen complex [Co(12-TMC)O] using HO as an [O] unit source.

The reaction of [M(L)] with HO as an [O] unit source and NEt as a base is a widely used biomimetic transition metal-peroxo and -superoxo complex [M(L)O] synthesis method, but the mechanism and accurate stoichiometry of the synthesis remain elusive. In this study, we performed DFT calculations to deeply understand the mechanism, using the synthesis of the cobalt-peroxo complex [Co(12-TMC)O] (12-TMC = (1,4,7,10-tetramethyl-1,4,7,10-tetraazacyclododecane)) from the reaction of [Co(12-TMC)] and HO in the presence of NEt as an example. The study found that cobalt-peroxo complex formation proceeds three stages: (Stage I) the conversion of [Co(12-TMC)] and HO to [Co(12-TMC)OH] and OOH˙ radical, (Stage II) the coordination of OOH˙ to [Co(12-TMC)] to give [Co(12-TMC)OOH], followed by deprotonation with NEt, affording [Co(12-TMC)O], and (Stage III) the transformation of [Co(12-TMC)OH] which is generated in Stage I to [Co(12-TMC)O].

Synthesis, Structural Characterization and Catalytic Application of Ferrocenyl Based Bis(pyrazolyl) Palladium Complexes.

Here we report, synthesis of ferrocenyl based bis(pyrazolyl) palladium complexes. The catalytic utility of the complexes in the cross-coupling of triarylbismuthanes and aryl bromides was evaluated. Our ferrocenyl based palladium complex showed wide substrate scope for both triarylbismuthanes and aryl bromides.

Conjugated Polymer-Based Photo-Crosslinker for Efficient Photo-Patterning of Polymer Semiconductors.

Photo-patterning of polymer semiconductors using photo-crosslinkers has shown potential for organic circuit fabrication via solution processing techniques. However, the performance of patterning, including resolution (R), UV light exposure dose, sensitivity (S), and contrast (γ), remains unsatisfactory. In this study, a novel conjugated polymer based photo-crosslinker (PN3, Figure 1a) is reported for the first time, which entails phenyl-substituted azide groups in its side chains.

Pyrazole based palladacycles for the synthesis of β-aminoketones by redox coupling of allyl alcohols and anilines.

Herein, we report the synthesis of β-aminoketones by oxidative coupling of allyl alcohols at room temperature using a pyrazole based palladacycle and BINOL-phosphoric acid system. This method avoids the use of any base, external oxidant, and additive. The reaction of -anisidine and 1-penten-3-ol under the optimized conditions using isolated palladacycle-BINOL-phosphoric acid produced the desired product in 24 h, which suggests that the active species involved in this reaction is the palladacycle-BINOL-phosphoric acid.

Analysis of forensic polymer samples using double shot pyrolysis gas chromatography - Mass spectrometry.

Polymers are present in many different products, such as paints, plastics, and rubbers, which are routinely encountered in forensic casework. Comparison of such samples involves an initial visual examination followed by comparison of the chemical compositions of the exhibits. Techniques such as Fourier transform infrared spectroscopy (FTIR) and pyrolysis gas chromatography - mass spectrometry (PyGC-MS) have been reported for determining the chemical compositions of polymers in forensic samples.

Optical force and torque in near-field excitation of C3H6: A first-principles study using RT-TDDFT.

Optical trapping is an effective tool for manipulating micrometer-sized particles, although its application to nanometer-sized particles remains difficult. The field of optical trapping has advanced significantly, incorporating more advanced techniques such as plasmonic structures. However, single-molecule trapping remains a challenge.

Cu(II) Coordination Polymers for the Selective Oxidation of Biomass-Derived Veratryl Alcohol in Green Solvents: A Sustainable Catalytic Approach.

Four air-stable one-dimensional copper(II) coordination polymers (-) with azide linkers were synthesized using tridentate NNS and NNN ligands. Single-crystal X-ray diffraction (XRD) analysis confirmed the molecular structures of , , and . In the presence of TEMPO, all four coordination polymers demonstrated effective catalytic activity for the selective aerobic oxidation of veratryl alcohol, a biomass model compound, under base-free conditions.

Application of bacterial-derived long cellulose nanofiber to suspension culture of mammalian cells as a shear protectant.

Nanofibrillated bacterial cellulose (NFBC) is a bio-compatible long-fiber nanocellulose produced by cellulose-synthesizing bacteria. It forms an entangled network structure in the suspension state, thereby imparting greater viscosity than conventional media additives. In this study, we examined its application as a shear protectant in the suspension culture of mammalian cells to mitigate hydrodynamic stress imposed on the cells.

Ru Prussian blue analogue-derived Ru nanoparticles composited with a trace amount of Pt as an efficacious electrocatalyst for the hydrogen evolution reaction.

In this work, we designed a straightforward and highly reproducible synthetic methodology to prepare Ru-Pt composites. We report a significant improvement in the electrocatalytic performance upon compositing Ru with a very trace amount of Pt. In particular, Ru nanoparticles were derived from a Ru-Prussian blue analogue (Ru PBA) and composited with (0.

Efficient one-step synthesis of diarylacetic acids by electrochemical direct carboxylation of diarylmethanol compounds in DMSO.

An efficient one-step synthesis of diarylacetic acids was successfully performed by electrochemical direct carboxylation of diarylmethanol compounds in DMSO. Constant-current electrolysis of diarylmethanol species in DMSO using a one-compartment cell equipped with a Pt cathode and a Mg anode in the presence of carbon dioxide induced reductive C(sp)-O bond cleavage at the benzylic position in diarylmethanol compounds and subsequent fixation of carbon dioxide to produce diarylacetic acids in good yield. This protocol provides a novel and simple approach to diarylacetic acids from diarylmethanol species and carbon dioxide without transformation of the hydroxy group into appropriate leaving groups, such as halides and esters including carbonates.

Achieving over 90% Faradaic Efficiency in Cyclohexanone Oxime Electrosynthesis Using the Cu-Mo Dual-Site Catalyst.

Coupling with the nitrate electroreduction reaction (NitRR), the electrosynthesis of cyclohexanone oxime (CHO, the vital feedstock in the nylon-6 industry) from cyclohexanone provides a promising alternative to the traditional energy consumption process. However, it still suffers from low efficiency because selective production of *NHOH intermediate from NitRR under large current densities is challenging. We here report a CuMoO/nitrogen-doped carbon (NC) electrocatalyst with high-density Cu-Mo dual sites for NitRR to selectively produce and stabilize *NHOH, with the subsequent cyclohexanone oximation achieving the highest CHO Faradaic efficiency of 94.

Liraglutide innovations: a comprehensive review of patents (2014-2024).

Type-2 diabetes mellitus (T2DM) is a complicated long-term disorder associated with metabolism that is identified by insulin resistance, imbalance in glucose regulation and reduced secretion of insulin. GLP-1(Glucagon-like peptide-1) is an incretin mimetic that has excellent effects on the regulation of blood glucose levels and also the management of disorders associated with vital organs. GLP-1 agonist is an effective class of drug for the treatment of type-2 diabetes mellitus and associated complications.

High-loading ficin@AuNPs on polymer-UiO-66 surface with enhanced peroxidase-mimetic catalytic activity for colourimetric detection of dopamine.

Recently, MOFs@AuNPs composites-based catalysts via anchoring of AuNPs onto metal-organic-frameworks (MOFs) have attracted great attention. However, the influence of the AuNPs loading amounts on the catalytic activity of MOFs@AuNPs composites remains largely unexplored. Here, ficin (Fic) protected AuNPs (Fic@AuNPs) anchored onto the surface of UiO-66-NH (UiO) modified with poly(2-vinyl-4,4-dimethyl-2-oxazolidine) (PV) were designed and constructed.

Molecular Photoswitching Unlocks Glucose Oxidase for Synergistically Reinforcing Fenton Reactions for Antitumor Chemodynamic Therapy.

We have developed a new type of nanoparticles with potent antitumor activity photoactivatable via the combination of molecular photoswitching of spiropyran (SP) and enzymatic reaction of glucose oxidase (GOx). As two key processes involved therein, Fe(III)-to-Fe(II) photoreduction in Fe(III) metal-organic frameworks (MOFs) brings about the release of free Fe/Fe while the photoswitching of SP to merocyanine (MC) unlocks the enzymatic activity of GOx that was pre-passivated by SP. The release of free Fe boosts its hydrolysis and therefore enables the acidification of microenvironment, which is further reinforced by one of the products of the GOx-mediated glucose oxidation reaction, gluconic acid (GlcA).

Regioselective Electrochemical Construction of C-C Linkage at C5-C5' Position of 2-Oxindoles via an Intermolecular Anodic Dehydrogenative Coupling.

Applying electricity as a reagent in synthetic organic chemistry has attracted particular attention from synthetic chemists worldwide as an environmentally benign and cost-effective technique. Herein, we report the construction of the C-C linkage at the C5-C5' position of 2-oxindole utilizing electricity as the traceless oxidant in an anodic dehydrogenative homo-coupling process. A variety of 3,3-disubstituted-2-oxindoles were subjected to dimerization, achieving yields of up to 70 % through controlled potential electrolysis at an applied potential of 1.

Y-Shaped Acceptor-π-Donor-π-Acceptor Configured Anthraquinone-Tethered Phenothiazine Molecular Scaffold for High-Performance Organic Pseudocapacitors.

For the first time acceptor-π-donor-π-acceptor (A-π-D-π-A) based Y-type organic electrode material have been designed and successfully utilized in supercapacitor (SC) application. This Y-type molecular architecture coined as AQ-Im-PTZ-Im-AQ based on anthraquinone (AQ) (A)-imidazole (Im) (π)-phenothiazine (PTZ) (D)-imidazole (Im) (π)-anthraquinone (AQ) (A) in combination with graphite foil (GF). As-fabricated PTZ-Im-AQ/GF and AQ-Im-PTZ-Im-AQ/GF electrode have shown the good energy storage properties in three-electrode supercapacitor system.