Auxetic and multiferroic MP5 (M = Al, Ga): a novel 2D material with negative Possion's ratio and high anisotropic carrier mobility.

In the field of materials science, the development of multifunctional 2D materials has been a long-standing research objective. In this study, we employ first-principles calculations to predict a novel 2D material named MP5 (M = Al, Ga), which exhibits ferroelasticity, ferroelectricity, negative Poisson's ratio, and high anisotropic carrier mobility. Our investigation reveals that a single layer of MP5 displays multiferroic behavior, wherein ferroelasticity and ferroelectricity are coupled. The remarkable structural anisotropy of MP5 enables easy switching between ferroelastic and ferroelectric states, rendering it suitable for nonvolatile memory applications. Simultaneously, monolayer AlP5 (GaP5) demonstrates a negative Poisson's ratio of -0.074 (-0.058) and a carrier mobility of up to 91 720 cm2 V-1 S-1 (99 690 cm2 V-1 S-1). These exceptional properties position monolayer MP5 as a highly versatile and promising 2D material for implementation in nanomechanical and microelectromechanical devices.

Synthesis of Enantioenriched 1,2-cis Disubstituted Cycloalkanes by Convergent NiH Catalysis.

Enantioenriched multi-substituted cycloalkanes constitute an essential class of compounds in pharmaceuticals, natural products and agrochemicals. Here we report an NiH-catalyzed asymmetric migratory hydroalkylation process for the efficient and selective construction of such compounds. Through a dynamic kinetic asymmetric transformation (DYKAT), easily accessible racemic and isomeric mixtures of cycloalkenes could be directly utilized as starting materials, convergently producing thermo-dynamically disfavored chiral 1,2-cis disubstituted cycloalkanes bearing vicinal stereocenters with high levels of regio-, diastereo- and enantioselectivity. In addition, prochiral cyclic alkenes can be also employed, and deliver chiral 1,2-cis disubstituted cycloalkanes through desymmetrization process.

Two-dimensional ferroelasticity and negative Poisson's ratios in monolayer YbX (X = S, Se, Te).

Two-dimensional ferroelastic materials and two-dimensional materials with negative Poisson's ratios have attracted great interest. Here, using first-principles calculations, we reveal monolayer YbX (X = S, Se, Te) materials that harbor both ferroelasticity and negative Poisson's ratios. Indirect wide band gaps of about 3 eV have been found in these three materials. Mechanical analysis reveals that the three materials are flexible and they possess large in-plane negative Poisson's ratios from -0.114 to -0.366. Meanwhile, the ferroelasticity in the monolayer YbX shows moderate energy barriers and strong ferroelastic signals, beneficial for applications in shape memory devices. These intriguing properties make monolayer YbX promising candidate materials for applications in nanoelectronics and nanomechanics.

BIAN-NHC Ligands in Transition-Metal-Catalysis: A Perfect Union of Sterically Encumbered, Electronically Tunable N-Heterocyclic Carbenes?

The discovery of NHCs (NHC = N-heterocyclic carbenes) as ancillary ligands in transition-metal-catalysis ranks as one of the most important developments in synthesis and catalysis. It is now well-recognized that the strong σ-donating properties of NHCs along with the ease of scaffold modification and a steric shielding of the N-wingtip substituents around the metal center enable dramatic improvements in catalytic processes, including the discovery of reactions that are not possible using other ancillary ligands. In this context, although the classical NHCs based on imidazolylidene and imidazolinylidene ring systems are now well-established, recently tremendous progress has been made in the development and catalytic applications of BIAN-NHC (BIAN = bis(imino)acenaphthene) class of ligands. The enhanced reactivity of BIAN-NHCs is a direct result of the combination of electronic and steric properties that collectively allow for a major expansion of the scope of catalytic processes that can be accomplished using NHCs. BIAN-NHC ligands take advantage of (1) the stronger σ-donation, (2) lower lying LUMO orbitals, (3) the presence of an extended π-system, (4) the rigid backbone that pushes the N-wingtip substituents closer to the metal center by buttressing effect, thus resulting in a significantly improved control of the catalytic center and enhanced air-stability of BIAN-NHC-metal complexes at low oxidation state. Acenaphthoquinone as a precursor enables facile scaffold modification, including for the first time the high yielding synthesis of unsymmetrical NHCs with unique catalytic properties. Overall, this results in a highly attractive, easily accessible class of ligands that bring major advances and emerge as a leading practical alternative to classical NHCs in various aspects of catalysis, cross-coupling and C-H activation endeavors.

Palladium-catalyzed ortho-selective C­H fluorination of oxalyl amide-protected benzylamines.

A novel and efficient synthetic method for o-fluorobenzylamines via palladium catalyst using an easily accessible oxalyl amide as directing group has been developed. The cheap N-fluorobenzenesulfonimide could be used as an effective [F+] source and t-amyl-OH as the solvent with Pd(OAc)2 as catalyst. Selective mono- or difluorination of oxalyl amide-protected benzylamine derivatives were achieved by modifying the reaction conditions, which presented an efficient method for the preparation of ortho-fluorinated benzylamines.

Easily accessible auxiliary for palladium-catalyzed intramolecular amination of C(sp²)-H and C(sp³)-H bonds at δ- and ε-positions.

An easily synthesized and accessible N,O-bidentate auxiliary has been developed for selective C-H activation under palladium catalysis. The novel auxiliary showed its first powerful application in C-H functionalization of remote positions. Both C(sp(2))-H and C(sp(3))-H bonds at δ- and ε-positions were effectively activated, thus giving tetrahydroquinolines, benzomorpholines, pyrrolidines, and indolines in moderate to excellent yields by palladium-catalyzed intramolecular C-H amination.

The Role of Emodin in the Treatment of Bladder Cancer based on Network Pharmacology and Experimental Verification.

BACKGROUND AND PURPOSE: Emodin, a compound derived from rhubarb and various traditional Chinese medicines, exhibits a range of pharmacological actions, including antiinflammatory, antiviral, and anticancer properties. Nevertheless, its pharmacological impact on bladder cancer (BLCA) and the underlying mechanism are still unclear. This research aimed to analyze the pharmacological mechanisms of Emodin against BLCA using network pharmacology analysis and experimental verification. METHODS: Initially, network pharmacology was employed to identify core targets and associated pathways affected by Emodin in bladder cancer. Subsequently, the expression of key targets in normal bladder tissues and BLCA tissues was assessed by searching the GEPIA and HPA databases. The binding energy between Emodin and key targets was predicted using molecular docking. Furthermore, in vitro experiments were carried out to confirm the predictions made with network pharmacology. RESULTS: Our analysis identified 148 common genes targeted by Emodin and BLCA, with the top ten target genes including TP53, HSP90AA1, EGFR, MYC, CASP3, CDK1, PTPN11, EGF, ESR1, and TNF. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses indicated a significant correlation between Emodin and the PI3KAKT pathway in the context of BLCA. Molecular docking investigations revealed a strong affinity between Emodin and critical target proteins. In vitro experiments demonstrated that Emodin inhibits T24 proliferation, migration, and invasion while inducing cell apoptosis. The findings also indicated that Emodin reduces both PI3K and AKT protein and mRNA expression, suggesting that Emodin may mitigate BLCA by modulating the PI3K-AKT signaling pathway. CONCLUSION: This study integrates network pharmacology with in vitro experimentation to elucidate the potential mechanisms underlying the action of Emodin against BLCA. The results of this research enhance our understanding of the pharmacological mechanisms by which Emodin may be employed in treating BLCA.

The joint effect of hOGG1 genotype and smoking habit on endometriosis in Taiwan.

This study has two aims: [1] to evaluate the association between hOGG1 genotypic polymorphism and endometriosis risk, and [2] to investigate the joint effects of hOGG1 genotype and smoking habit on endometriosis susceptibility in Taiwan. For this purpose, the well-known polymorphic variants of hOGG1, codon 326, was genotyped and analyzed of its association with the risk of endometriosis. In total, 153 patients with endometriosis and 636 non-endometriosis healthy controls were recruited and genotyped. The methodology for genotyping is polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Pearson's Chi-square test was performed to compare the distributions of the genotypes between case and control groups. The results showed that the hOGG1 codon 326 genotypes were not differently distributed between the endometriosis and non-endometriosis control groups in both genotypic (P = 0.6212) and allelic (P = 0.4006) frequency analysis. We have further analyzed the genotypic-smoking joint effects on endometriosis risk and found an obvious interaction between hOGG1 codon 326 genotypes and smoking status. The hOGG1 codon 326 genotypes were increased in endometriosis risk only in the smoker groups (P = 0.0061), but not in the non-chewer group (P = 0.0648). Our results provide the evidence that the hOGG1 codon 326 genotype may have a joint effect with smoking on the development of endometriosis.

Chromium-Catalyzed Diastereoselective Synthesis of Conformationally Constrained Spirotetrahydroquinolines.

We report the diastereoselective cyclization of anilines with cyclobutanones and congeners by chromium catalysis. This reaction can link two strained four-membered rings with tetrahydroquinolines by forming four bonds in a diastereocontrolled manner, forming medicinally interesting cyclobutane-fused and constrained spirotetrahydroquinolines (STHQs) and complex multiple spiro carbon-containing polyazacycles. The constrained STHQs have been used as versatile feedstocks to derive a range of oxygen-, nitrogen-, and thio-substituted spiro analogues, and dioxygen-incorporated spiroazacycles.

Chromium-Catalyzed Activation of Acyl C-O Bonds with Magnesium for Amidation of Esters with Nitroarenes.

Here, we report a chromium-catalyzed activation of acyl C-O bonds with magnesium for amidation of esters with nitroarenes. Low-cost chromium(III) chloride shows high reactivity in promoting amidation by using magnesium as reductant and chlorotrimethylsilane as additive. It provides a step-economic strategy to the synthesis of centrally important amide motifs using inexpensive and air-stable nitroarenes as amino sources.

Chromium-catalyzed para-selective formation of quaternary carbon centers by alkylation of benzamide derivatives.

Selective creation of quaternary carbon centers has been a long-standing challenge in synthetic chemistry. We report here the chromium-catalyzed, para-selective formation of arylated quaternary carbon centers by alkylative reactions of benzamide derivatives with tertiary alkylmagnesium bromides at room temperature. The reaction, which was enabled by a low-cost chromium(III) salt combined with trimethylsilyl bromide, introduces a sterically bulky tertiary alkyl scaffold on the para-position of benzamide derivatives in a highly selective fashion without either isomerization of the tertiary alkyl group or formation of ortho-alkylated byproducts. Forming low-valent Cr species in situ by reaction of CrCl3 with t-BuMgBr accompanied by evolution of hydrogen can be considered, which serves as reactive species to promote the reaction. The para-alkylation likely occurs via a radical-type nucleophilic substitution of imino-coordination benzimidate intermediate.

Ruthenium(II)-enabled para-selective C-H difluoromethylation of anilides and their derivatives.

Transition-metal-catalyzed direct site-selective functionalization of arene C-H bonds has emerged as an innovative approach for building the core structure of pharmaceutical agents and other versatile complex compounds. However, para-selective C-H functionalization has seldom been explored, only a few examples, such as steric-hindered arenes, electron-rich arenes, and substrates with a directing group, have been reported to date. Here we describe the development of a ruthenium-enabled para-selective C-H difluoromethylation of anilides, indolines, and tetrahydroquinolines. This reaction tolerates various substituted arenes, affording para-difluoromethylation products in moderate to good yields. Results of a preliminary study of the mechanism indicate that chelation-assisted cycloruthenation might play a role in the selective activation of para-CAr-H bonds. Furthermore, this method provides a direct approach for the synthesis of fluorinated drug derivatives, which has important application for drug discovery and development.

Iridium-Catalyzed, Weakly Coordination-Assisted Ortho-Alkynylation of (Hetero)aromatic Carboxylic Acids without Cyclization.

It is reported a weakly coordination-assisted alkynylation of aryl and heteroaryl carboxylic acids with iridium catalysis. The reaction is catalyzed by [{Cp*IrCl2}2] complex without cyclization, forming ortho-alkynylated aryl and heteroaryl carboxylic acids, and features high functional group tolerance and broad substrate scope under an air atmosphere. 2-(Hetero)aryl-substituted acetic acids were amenable to the alkynylation by forming an unusual six-membered ring cycloiridiated intermediate.

Palladium-catalyzed oxalyl amide assisted direct ortho-alkynylation of arylalkylamine derivatives at δ and ε positions.

Palladium-catalyzed oxalyl amide directed ortho-alkynylation of arylalkylamine derivatives is reported for the first time. A wide variety of ß-arylethamine and γ-arylpropamine derivatives are compatible with this protocol. This method provides a general means to synthesize substituted alkynylarylalkylamine derivatives, highlighting the ability of oxalyl amide in promoting C-H functionalization at unique δ and ε positions.

Palladium-Catalyzed Oxalyl Amide Directed Silylation and Germanylation of Amine Derivatives.

Palladium-catalyzed direct ortho-silylation of oxalyl amide-protected phenylmethanamine and phenethylamine with commercially available disilanes is reported. Germanylation products were also produced under the same reaction conditions. This protocol tolerated oxalyl amide-protected aliphatic amines, which gave γ-C-H silylation products.

Oxalyl amide assisted palladium-catalyzed synthesis of pyrrolidones via carbonylation of γ-C(sp3)-H bonds of aliphatic amine substrates.

The first Pd-catalyzed regioselective γ-carbonylation of oxalyl amide protected aliphatic amines with carbon monoxide leading to synthesis of pyrrolidones has been developed. Both γ-methyl and cyclopropyl methylene C-H bonds are well activated to obtain the corresponding pyrrolidones in moderate to excellent yields. The role of 3-(trifluoromethyl)benzoic acid as an additive is critical as it helps in stabilizing the palladium intermediate formed during the catalytic cycle. The reaction scope is extended to benzylamine and allyl amine derivatives, thereby affording the corresponding products in good to excellent yields.

Facial palsy as unusual complication of spontaneous intraparotid hematoma.

A 55-year-old healthy female without trauma history visited our hospital for rapidly progressive enlarging right side painful neck mass within 5 days and also with comorbid House-Brackmann Grade V facial palsy for 2 days. Magnetic resonance imaging showed heterogenous mass derived from parotid to parapharyngeal space. Much blood clot could be observed at exploratory operation. Only inflammatory change, but not tumor, was mentioned in pathology report. Facial palsy was kept stationary in Grade III from postoperative 6 months.