Synthesis of Allenes by Catalytic Coupling of Propargyl Carbonates with Aryl Iodides in the Presence of Diboron Species

Bimetallic copper-/palladium-catalyzed multicomponent reaction of propargyl carbonates, aryl iodides, and diboron species was studied. This procedure can be used for synthesis of di-, tri-, and tetra-substituted allenes. Using diboronic acid, the reaction is supposed to proceed via allenylboronic acid intermediate

Synthesis of Indolizines via Palladium Catalyzed Annulation of Propargyl Carbonates and 2‑(Pyridin-2-yl)acetonitrile Derivatives

A Pd-catalyzed regioselective annulation reaction of propargyl carbonates and 2-(pyridine-2-yl) acetonitrile derivatives has been accomplished, which provides a straightforward and efficient access to polysubstituted indolizines. The choice of the phosphine ligand is crucial to the high regio-selectivity of the reaction

Synthesis of Indolizines via Palladium Catalyzed Annulation of Propargyl Carbonates and 2‑(Pyridin-2-yl)acetonitrile Derivatives

A Pd-catalyzed regioselective annulation reaction of propargyl carbonates and 2-(pyridine-2-yl) acetonitrile derivatives has been accomplished, which provides a straightforward and efficient access to polysubstituted indolizines. The choice of the phosphine ligand is crucial to the high regio-selectivity of the reaction

Synthesis of Polysubstituted Furans via Copper-Mediated Annulation of Alkyl Ketones with α,β-Unsaturated Carboxylic Acids

A novel copper-mediated annulation of alkyl ketones with α,β-unsaturated carboxylic acids has been accomplished. This reaction provides a facile and regio-defined method for the synthesis of 2,3,5-trisubstituted furans from simple chemical reagents

Synthesis of Functionalized Indolizines via Copper-Catalyzed Annulation of 2-Alkylazaarenes with α,β-Unsaturated Carboxylic Acids

A novel copper-catalyzed annulation of 2-alkylazaarenes with <b>α,β</b>-unsaturated carboxylic acids has been accomplished. This reaction featuring C–H olefination and decarboxylative amination processes provides a concise access to C-2 arylated indolizines from simple and readily available starting materials

Palladium-Catalyzed Direct C-3 Alkynylation of Indolizines with (2,2-Dibromovinyl)arenes

<div><p></p><p>The direct C-3 alkynylation of indolizines with (2,2-dibromovinyl)arenes in the presence of palladium catalyst has been developed. This novel protocol showed wide substrate scope with respect to both indolizines and dibromoalkenes. Also this method was characterized with high efficiency and good functional group tolerance.</p> </div

Pd-Catalyzed Arylation/Oxidation of Benzylic C–H Bond

A palladium-catalyzed benzylic C–H arylation/oxidation reaction leading to diaryl ketones has been accomplished. The indispensable role of the bidentate system is disclosed for this sequential process. This chemistry offers a direct new access to a range of diarylketones

Finite element analysis of sagittal angles of unicompartmental knee arthroplasty

BackgroundUnicompartmental knee arthroplasty is an effective treatment for knee osteoarthritis, but it has the risk of failure, and the installation position of the prosthesis is one of the factors affecting the failure. There are few biomechanical studies on the installation angle of unicompartmental knee prosthesis.MethodsConstructed a finite element model of a normal human knee joint, and the validity of the model was verified by stress and front anterior methods. The mobile-bearing unicompartmental knee arthroplasty femoral prosthesis was placed at 3° intervals from 0° sagittal plane to 15° flexion, and − 2° and 17°were established, and observing the biomechanical changes of components.FindingsMaximum peak stresses occurred at a sagittal mounting angle of −2° for the insert and the contralateral meniscus, with the tibia showing a maximum at 17° sagittal and the tibial prosthesis stress maximum occurring at 6° sagittal. As the sagittal plane angle of the femoral prosthesis increases and the osteotomy distance extends posteriorly, more bone is amputated during the osteotomy. The ratio of the distance from the tip of the anterior intramedullary nail to the anterior end of the osteotomy to the total anteroposterior length of the sagittal osteotomy ranged from 43.2% to 44.6%.InterpretationIn this paper, the more appropriate sagittal mounting position for the femoral prosthesis is between 9 and 12°, based on the amount of osteotomy and the peak stress of each component in a standing position.</p

Tea Polyphenol Epigallocatechin Gallate Protects Against Nonalcoholic Fatty Liver Disease and Associated Endotoxemia in Rats via Modulating Gut Microbiota Dysbiosis and Alleviating Intestinal Barrier Dysfunction and Related Inflammation

Nonalcoholic fatty liver disease (NAFLD) is characterized by fat accumulation and inflammation. Epigallocatechin gallate (EGCG) has been proven to be effective against NAFLD, but its hepatoprotective mechanisms based on the “gut microbiota-barrier-liver axis” are still not fully understood. Herein, the results demonstrated that EGCG effectively ameliorated NAFLD phenotypes and metabolic disorders in rats fed a high-fat diet (HFD), and inhibited intestinal barrier dysfunction and inflammation, which is also supported in the experiment of Caco-2 cells. Moreover, EGCG could restore gut microbiota diversity and composition, particularly promoting beneficial microbes, including short-chain fatty acids (SCFAs) producers, such as Lactobacillus, and suppressing Gram-negative bacteria, such as Desulfovibrio. The microbial modulation raised SCFA levels, decreased lipopolysaccharide levels, inhibited the TLR4/NF-κB pathway, and strengthened intestinal barrier function via Nrf2 pathway activation, thereby alleviating liver steatosis and inflammation. Spearman’s correlation analysis showed that 24 key OTUs, negatively or positively associated with NAFLD and metabolic disorders, were also reshaped by EGCG. Our results suggested that a combinative improvement of EGCG on gut microbiota dysbiosis, intestinal barrier dysfunction, and inflammation might be a potential therapeutic target for NAFLD