Enzymatically Mediated In Situ Generation of Z-Scheme BiS/BiMoO Heterojunction-Based Organic Photoelectrochemical Transistor for METTL3/METTL14 Detection.

The OPECT biosensing platform, which connects optoelectronics and biological systems, offers significant amplification and more possibilities for research in biological applications. In this work, a homogeneous organic photoelectrochemical transistor (OPECT) biosensor based on a BiS/BiMoO heterojunction was constructed to detect METTL3/METTL14 protein activity. The METTL3/METTL14 complex enzyme was used to catalyze adenine (A) on an RNA strand to mA, protecting mA-RNA from being cleaved by an toxin (MazF).

Oxygen vacancy-rich β-BiO/BiOSiO Z-Scheme heterojunction: A strategy to enhance visible light-driven photocatalytic removal of ARB and ARGs.

Oxygen vacancy-rich β-BiO/BiOSiO (BO/BOS) Z-Scheme heterojunction was prepared by hydrothermal method-assisted calcination. Under visible light, β-BiO/BiOSiO photocatalyst demonstrated superior photocatalytic efficacy in degrading antibiotics and antibiotic-resistant Escherichia coli (AR E. coli) compared to individual β-BiO and BiOSiO.

MXene-Enhanced BiS/CdInS Heterojunction Photosensitive Gate for DEHP Detection in a Signal-On OPECT Aptamer Biosensor.

Organic electrochemical transistors with signal amplification and good stability are expected to play a more important role in the detection of environmental pollutants. However, the bias voltage at the gate may have an effect on the activity of vulnerable biomolecules. In this work, a novel organic photoelectrochemical transistor (OPECT) aptamer biosensor was developed for di(2-ethylhexyl) phthalate (DEHP) detection by combining photoelectrochemical analysis with an organic electrochemical transistor, where MXene/BiS/CdInS was employed as a photoactive material, target-dependent DNA hybridization chain reaction was used as a signal amplification unit, and Ru(NH) was selected as a signal enhancement molecule.

Copper(I)-Catalyzed Nitrosylation/Annulation Cascade of Enaminones with -Butyl Nitrite: Access to 1-1,2,3-Triazole 2-Oxides.

The direct synthesis of triazole 2-oxides has posed a challenge in the field of -heterocyclic chemistry. A novel copper(I)-catalyzed nitrosylation/annulation cascade of enaminones provides a straightforward route to 1-1,2,3-triazole 2-oxides by forming new C-N, N=N, and N-N bonds using noncorrosive -butyl nitrite (TBN) as both the N and NO sources. The synthetic protocol features easily accessible starting materials, wide substrate scopes, and good tolerance toward various functional groups while avoiding use of explosive azides.

Zinc(II)-Catalyzed [2+2+1] Annulation of Internal Alkenes, Diazooxindoles, and Isocyanates to Access Spirooxindoles.

Zinc(II)-catalyzed [2+2+1] annulation of internal alkenes, diazooxindoles, and isocyanates was successfully developed for the construction of multisubstituted spirooxindoles. This multicomponent transformation involves generation of a sulfur-containing spirocyclic intermediate from the [4+1] annulation of diazooxindole to sulfonyl isocyanate, which subsequently reacts as a 1,3-dipole with the internal alkene, that is, α-oxo ketene dithioacetal, to furnish a formal [2+2+1] annulation in a one-pot manner. This synthetic protocol features a low-toxicity main group metal catalyst, readily available reagents, and ≤96% yields, offering an efficient route to multisubstituted spirooxindole derivatives.

Scalable Palladium-Catalyzed Alkoxycarbonylation of Conjugated Dienes.

The Pd(cod)Cl-catalyzed alkoxycarbonylation of conjugated dienes to β,γ-unsaturated esters was approached by both intramolecular phosphinesulfonate L and intermolecular PPh/PTSA in this study. However, the poor solubility of the Pd/L complex and the labile monodentate Pd/PPh structure restricts the system efficiency, especially for the scale-up application. By contrast, the stable and well-soluble bidentate Xantphos system allows for the quantitative formation of 3-pentenoate (96%) on a gram scale within 6 h in weakly alkaline -methylpyrrolidone (NMP), which also functions as a basic site to promote the rate-limiting alcoholysis step while reducing the dosage of ligand to a theoretical value.

Rhodium(III)-Catalyzed Triple Aryl/Alkenyl C-H Bond Activation of Aryl Enaminones to Access Naphtho[1,8-]pyrans.

Rhodium(III)-catalyzed triple C-H bond activation of aryl enaminones was achieved to access naphtho[1,8-]pyrans by oxidative annulation to internal alkynes. 1-Naphthols might be formed as the only products, depending on the steric and/or electronic environment around the aroyl moiety of the aryl enaminones or the electronic impact from the alkynes. With propargyl alcohols as the masked terminal alkynes, aryl enaminones underwent rhodium(III)- or rhodium(I)-catalyzed internal alkenyl C-H bond activation to afford functionalized but-2-ene-1,4-diones.

Tunable Construction of Multisubstituted 1,3-Dienes and Allenes a 1,4-Palladium Migration/Carbene Insertion Cascade.

Efficient palladium-catalyzed vinylic C-H alkenylation and allenylation of -disubstituted ethylenes with -tosylhydrazones of aryl alkyl and diaryl ketones were achieved to access trisubstituted 1,3-dienes and tetrasubstituted allenes, respectively. An aryl to vinyl 1,4-palladium migration/carbene insertion/β-hydride elimination sequence proceeded to switch the chemo- and regioselectivities to give structurally diverse products. Use of 2-FCHOH additive enables enhancement of the reaction efficiency through accelerating the key 1,4-palladium migration process.

Recent advances in transition-metal-catalyzed carbene insertion to C-H bonds.

C-H functionalization has been emerging as a powerful method to establish carbon-carbon and carbon-heteroatom bonds. Many efforts have been devoted to transition-metal-catalyzed direct transformations of C-H bonds. Metal carbenes generated from transition-metal compounds and diazo or its equivalents are usually applied as the transient reactive intermediates to furnish a catalytic cycle for new C-C and C-X bond formation.

Copper-Catalyzed [4 + 1] Annulation of Enaminothiones with Indoline-Based Diazo Compounds.

A concise synthetic route to spiroindoline-fused -heterocycles was developed through copper-catalyzed [4 + 1] annulation using enaminothiones as donor-acceptor synthons. Both 3-diazoindolin-2-imines and 3-diazooxindoles were amenable to work as effective C1 building blocks. The reaction proceeds a copper-catalyzed cascade process involving the generation of copper(I) carbene and C-S/C-C bond formation.

Palladium-Catalyzed Fluoroalkylation via C(sp)-S Bond Cleavage of Vinylsulfonium Salts.

An interrupted Pummerer/palladium-catalyzed fluoro-alkylation strategy was developed for alkenyl C-H fluoroalkylthiolation. Palladium-catalyzed ring-opening fluoroalkylation via aliphatic C-S bond cleavage of the vinylsulfonium salts efficiently afforded fluoroalkylthiolated alkene derivatives from readily available alkene substrates and CsF. The protocol features broad substrate scopes and good functional group tolerance under an air atmosphere.

Visible-Light-Driven, Palladium-Catalyzed Heck Reaction of Internal Vinyl Bromides with Styrenes.

Functionalized 1,3-dienes were efficiently accessed from visible-light-driven, palladium-catalyzed Heck reaction of ,-functionalized internal vinyl bromides with styrenes under mild conditions. This Heck reaction showcased tolerance of a wide array of functional groups, afforded the target products in moderate to excellent yields through a radical reaction pathway. The resultant diene products could be further transformed to highly functionalized trisubstituted furan derivatives.

Cobalt-Catalyzed Chemoselective Transfer Hydrogenative Cyclization Cascade of Enone-Tethered Aldehydes.

The ligand-free Co-catalyzed chemoselective reductive cyclization cascade of enone-tethered aldehydes with -PrOH as the environmentally benign hydrogen surrogate is developed by this study. Mechanistic studies disclosed that such a protocol is initiated by an -enone-assisted Co(I)-catalyzed reduction of the aldehyde functionality with -PrOH. Meanwhile, the selectivity from the Michael-Aldol cycloreduction cascade to the oxa-Michael cascade is feasible and readily adjusted by the addition of steric Lewis bases, such as TEMPO and DABCO, delivering substituted 1-indenes and dihydroisobenzofurans, respectively.

Exposure to short-chain chlorinated paraffins inhibited PPARα-mediated fatty acid oxidation and stimulated aerobic glycolysis in vitro in human cells.

Short-chain chlorinated paraffins (SCCPs) could disrupt fatty acid metabolism in male rat liver through activating rat PPARα signaling. However, whether this mode of action can translate to humans remained largely unclear. In this study, based on luciferase assays, C-CPs (56.

Photoinduced, Copper-Catalyzed Three-Component Annulation of -Dialkylthio Enynes.

Photoinduced, copper-catalyzed three-component radical annulation of -dialkylthio enynes, cyclobutanone oxime esters, and boronic acids was achieved, forming highly functionalized aryl thienyl sulfides with both good chemo- and diastereoselectivities. The reaction proceeds through a domino sequence involving cyanoalkyl radical-mediated intramolecular annulation of -dialkylthio enyne, alkenyl radical-promoted C(sp)-S bond cleavage, and sulfur-centered radical-trapped Cu(II)-facilitated C-S cross-coupling. The protocol features simultaneous establishment of cyanoalkyl, cyclopentanone, and thiophene moieties and a thioether C-S bond in one pot with broad substrate scopes and versatile functional group tolerance under mild conditions.

Transition-metal mediated carbon-sulfur bond activation and transformations: an update.

Carbon-sulfur bond cross-coupling has become more and more attractive as an alternative protocol to establish carbon-carbon and carbon-heteroatom bonds. Diverse transformations through transition-metal-catalyzed C-S bond activation and cleavage have recently been developed. This review summarizes the advances in transition-metal-catalyzed cross-coupling via carbon-sulfur bond activation and cleavage since late 2012 as an update of the critical review on the same topic published in early 2013 (Chem.

Copper(II)-Mediated Intramolecular Cyclopropanation of Ketene ,-Acetals (X = S, O, N) under Mild Conditions.

CuBr-mediated intramolecular oxidative cyclopropanation of α-oxo ketene ,-acetals was efficiently achieved to afford 2-thioalkyl-3-azabicyclo-[3.1.0]hexenes under mild conditions.

ZnCl -Catalyzed [4+1] Annulation of Alkylthio-Substituted Enaminones and Enaminothiones with Sulfur Ylides.

Concise construction of furan and thiophene units has played an important role in the synthesis of potentially bioactive compounds and functional materials. Herein, an efficient Lewis acid ZnCl catalyzed [4+1] annulation of alkylthio-substituted enaminones is reported, that is, α-oxo ketene N,S-acetals with sulfur ylides to afford 2-acyl-3-aminofuran derivatives. In a similar fashion, [4+1] annulation of the corresponding enaminothiones, that is, α-thioxo ketene N,S-acetals, with sulfur ylides efficiently proceeded to give multisubstituted 3-aminothiophenes.

Copper-Catalyzed Annulative Coupling of S,S-Disubstituted Enones with Diazo Compounds to Access Highly Functionalized Thiophene Derivatives.

An efficient protocol toward fully substituted thiophenes and thieno[2,3-]thiophenes has been developed through CuCl-catalyzed annulative coupling of S,S-disubstituted enones with diazo compounds under mild conditions. Tetrasubstituted thiophenes and thieno[2,3-]thiophenes were efficiently accessed by variation of the feed ratio of the reactants in good to excellent yields, respectively. The synthetic methodology has demonstrated the potential for the construction of diverse thiophene derivatives.

Copper(II)-Catalyzed C-H Nitrogenation/Annulation Cascade of Ketene ,-Acetals with Aryldiazonium Salts: A Direct Access to -Substituted Triazole and Triazine Derivatives.

Direct synthesis of -substituted triazole and triazine derivatives has been a challenge in -heterocyclic chemistry. Under copper(II) catalysis ketene ,-acetals, that is, alkylthio-substituted enaminones, efficiently reacted with aryldiazonium salts to allow the regioselective generation of functionally diverse -substituted 1,2,3-triazoles and 2,3-dihydro-1,2,4-triazines. The oxidant and base-dependent reaction yielded the five- and six-membered -heterocyclic products, respectively.

Rhodium(III)-Catalyzed Annulative Coupling of Sulfoxonium Ylides and Allenoates: An Arene C-H Activation/Cyclopropanation Cascade.

Rhodium(III)-catalyzed annulative coupling of sulfoxonium ylides with allenoates was achieved, forming highly functionalized cyclopropanes with a quaternary carbon center by means of the sulfoxonium ylide functionality as a traceless bifunctional directing group and C4 synthon via an arene C-H activation and cyclopropanation cascade. The protocol features simultaneous formation of three new C-C bonds in one pot with excellent diastereoselectivity. The resultant cyclopropanation products could be further transformed to diverse synthetically useful compounds.

Short-chain chlorinated paraffins (SCCPs) disrupt hepatic fatty acid metabolism in liver of male rat via interacting with peroxisome proliferator-activated receptor α (PPARα).

Short-chain chlorinated paraffins (SCCPs) are frequently detected in environmental matrices and human tissues. It was hypothesized that SCCPs might interact with the peroxisome proliferator-activated receptor α (PPARα). In the present study, an in vitro, dual-luciferase reporter gene assay and in silico molecular docking analysis were employed together to study the interactions between SCCPs congeners and PPARα.

Rhodium(III)-Catalyzed Annulation of Acetophenone O-Acetyl Oximes with Allenoates through Arene C-H Activation: An Access to Isoquinolines.

Rhodium(III)-catalyzed annulation of acetophenone O-acetyl oximes with allenoates was achieved, affording isoquinolines in good to excellent yields with high regioselectivities under redox-neutral conditions. Allenoates acted as the C2 synthons in the annulation reaction. The present synthetic methodology features good functional group tolerance and avoids metal salts as the external oxidants.

Copper-Catalyzed Radical C-C Bond Cleavage and [4+1] Annulation Cascade of Cycloketone Oxime Esters with Enaminothiones.

Carbon-carbon bond formation is among the most important reactions in organic synthesis. Reconstruction of a carbon-carbon bond through ring-opening C-C bond cleavage of a strained carbocycle usually occurs via a thermodynamically preferable pathway. However, carbon-carbon bond formation through thermodynamically less favorable C-C bond cleavage has seldom been documented.