Electrooxidative Ni-catalyzed Decarboxylation of Arylacetic Acids towards the Synthesis of carbonyls under Air Conditions.

After systematic realization of decarboxylative functionalization of carboxylic acids under heating conditions in our group, we herein reported an electrochemical method for Ni-catalyzed decarboxylative oxygenation of arylacetic acids under open air conditions. The protocol provided corresponding carbonyls including aldehydes and ketones in moderate to satisfactory yields with good functional group tolerance, furthermore, the practicability and advantage of the method was highlighted through Ni-catalyzed oxidative decarboxylation of carboxylic acid-containing drugs and preformation of scalable transformation. Mechanistic studies demonstrated that the possible involvement of free radical intermediate in the conversion.

The Halogenation Effect Induces a Variety of Switchable Phase Transition and Second-Harmonic-Generation Materials.

Halogen engineering offers a means of enhancing the physical properties of materials by fine-tuning the rotational energy barrier and dipole moment, which proved to be effective in achieving switchable phase transitions and optical responses in materials. In this work, by substituting the methyl group in ligand N-ethyl-1,5-diazabicyclo[3.3.0]octane (CH3CH2-3.3.0-Dabco) with halogen atoms X (Cl or Br) and then contining to react it with FeBr3 in a HBr aqueous solution, we successfully synthesized three kinds of organic-inorganic hybrid switchable phase-change materials, [CH3CH2-3.3.0-Dabco]FeBr4 (1), [ClCH2-3.3.0-Dabco]FeBr4 (2), and [BrCH2-3.3.0-Dabco]FeBr4 (3), which were fully characterized by single-crystal X-ray diffraction and variable-temperature powder X-ray diffraction. Compared to compound 1, compounds 2 and 3 show two pairs of reversible phase transitions, dielectric anomalies, and a second-harmonic-generation effect, which are successfully induced due to the halogen substitution. This study offers an effective molecular design strategy for the exploration and construction of iron halide organic-inorganic hybrid materials with temperature-adjustable physical properties.

The First Discovery of Spherical Carborane Molecular Ferroelectric Crystals.

Carborane compounds, known for their exceptional thermal stability and non-toxic attributes, have garnered widespread utility in medicine, supramolecular design, coordination/organometallic chemistry, and others. Although there is considerable interest among chemists, the integration of suitable carborane molecules into ferroelectric materials remains a formidable challenge. In this study, we employ the quasi-spherical design strategy to introduce functional groups at the boron vertices of the o-carborane cage, aiming to reduce molecular symmetry. This approach led to the successful synthesis of the pioneering ferroelectric crystals composed of cage-like carboranes: 9-OH-o-carborane (1) and 9-SH-o-carborane (2), which undergo above-room ferroelectric phase transitions (Tc) at approximately 367 K and 347 K. Interestingly, 1 and 2 represent uniaxial and multiaxial ferroelectrics respectively, with 2 exhibiting six polar axes and as many as twelve equivalent polarization directions. As the pioneering instance of carborane ferroelectric crystals, this study introduces a novel structural archetype for molecular ferroelectrics, thereby providing fresh insights into the exploration of molecular ferroelectric crystals with promising applications.

Efficient synthesis of α-amino-vinylphosphine oxides from alkyl nitriles via manganese-catalyzed phosphinoenamination.

A protocol for the synthesis of α-amino-vinylphosphine oxides by phosphinoenamination reaction between alkyl nitriles and phosphine oxides was developed. The combination of Mn(OAc)2 as a Lewis acid and guanidine as a Lewis base was found to be an efficient catalytic system for this reaction. A series of alkyl nitriles and phosphine oxides are compatible with this conversion, furnishing the desired products in up to 95% yield under mild conditions. Furthermore, this method demonstrates the capability of gram-scale synthesis.

Pd-Catalyzed Enantioselective Desymmetrizing 1,7-Enyne Cycloisomerization of Alkyne-Tethered Cyclopentenes.

An enantioselective Pd-catalyzed intramolecular desymmetrizing cycloisomerization of N-(cyclopent-3-en-1-yl)propiolamides has been developed by employing a new chiral phosphoramidite ligand. A series of structurally unique bridged azabicycles are achieved in moderate to excellent yields with good E/Z selectivity and high enantioselectivity. Synthetic transformations are conducted to demonstrate the practical utility of this reaction.

Para-selective nitrobenzene amination lead by C(sp2)-H/N-H oxidative cross-coupling through aminyl radical.

Arylamines, serving as crucial building blocks in natural products and finding applications in multifunctional materials, are synthesized on a large scale via an electrophilic nitration/reduction sequence. However, the current methods for aromatic C-H amination have not yet attained the same level of versatility as electrophilic nitration. Here we show an extensively investigated transition metal-free and regioselective strategy for the amination of nitrobenzenes, enabling the synthesis of 4-nitro-N-arylamines through C(sp2)-H/N-H cross-coupling between electron-deficient nitroarenes and amines. Mechanistic studies have elucidated that the crucial aspects of these reactions encompass the generation of nitrogen radicals and recombination of nitrobenzene complex radicals. The C(sp2)-N bond formation is demonstrated to be highly effective for primary and secondary arylamines as well as aliphatic amines under mild conditions, exhibiting exceptional tolerance towards diverse functional groups in both nitroarenes and amines (>100 examples with yields up to 96%). Notably, this C(sp2)-H/N-H cross-coupling exhibits exclusive para-selectivity.

Unexpected 99mTc-pertechnetate avidity of lymph node metastases predicts better response to radioiodine therapy in differentiated thyroid cancer patients with lymph node metastases.

OBJECTIVE: To investigate the value of 99mTc-pertechnetate scan in postoperative differentiated thyroid cancer (DTC) patients with lymph node (LN) metastases (LNM) uptake 99mTc-pertechnetate, especially the predictive value to their response to radioiodine-131 (131I) therapy. METHODS: This retrospective study collected 752 patients with DTC and LNM treated at Zhejiang Cancer Hospital between May 2012 and December 2017. Depending on the ability of LNM uptake 99mTc-pertechnetate, the patients were grouped as the 99mTc-pertechnetate-avid (n=88) vs. 99mTc-pertechnetate-non-avid (n=664) groups. And Propensity score matching (PSM) was performed at a 1:4 ratio to reduce confounding bias. RESULTS: In the PSM analysis, the 1:4 matched cohort comprised 752 patients (88 with 99mTc-pertechnetate-avid LNM, 664 with 99mTc-pertechnetate-non-avid LNM). Patients' age, initial 131I activity and frequency of iodine therapy were included as covariates. After PSM analysis, 363 patients (99mTc-pertechnetate-avid group, n=83; 99mTc-pertechnetate-non-avid group, n=280) were successfully matched. Among the 363 PSM-matched patients, 48/83 (57.8%) in the 99mTc-pertechnetate-avid group and 158/280 (56.4%) in the 99mTc-pertechnetate-non-avid group had two or more 131I treatments. The nsTg and the percentage of changes in ssTg between the 99mTc-pertechnetate-avid and 99mTc-pertechnetate-non-avid groups were significantly different ([0.05 (0.04 to 0.90) vs. 0.40 (0.04 to 4.92), p=0.018] and [-88% (-98%, -50%) vs. -66% (-86%, -30%), p < 0.001], respectively). No significant differences were observed between the two groups in the other parameters (age, pathological type, distant metastasis, follow-up time, AJCC TNM stage, initial 131I treatment activity, and 131I treatment frequency) after PSM (all p > 0.05). CONCLUSION: In patients with DTC and LNM, LNM uptake of 99mTc-pertechnetate is a rare phenomenon. Patients with 99mTc-pertechnetate-avid LNMs were more likely to benefit from 131I therapy, even after adjustment for age, 131I treatment frequency, and initial 131I activity.

Establishment of virus-induced gene-silencing system in Juglans sigillata Dode and functional analysis of JsFLS2 and JsFLS4.

Juglans sigillata Dode is one of the important tree species in southwest China, and it has significant economic and ecological value. However, there is still a lack of effective methods to identify the functional genes of J. sigillata. By verifying the model plant tobacco, the pTRV2::JsPDS vector was able to cause photobleaching. This study showed that photobleaching occurred 24 and 30 d after the silencing vector was infected with aseptic seedlings and fruits of J. sigillata, respectively. When the OD600 was 0.6, and the injection dose was 500 µL, the gene silencing efficiency of aseptic seedlings was the highest at 16.7 %, significantly better than other treatments. Moreover, when the OD600 was 0.8, and the injection dose was 500 µL, the gene silencing efficiency in the walnut fruit was the highest (20 %). In addition, the VIGS system was successfully used to silence JsFLS2 and JsFLS4 genes in J. sigillata. This study also showed that the flavonol content and gene expression in the treatment group were decreased compared to the control group. In addition, the proteins transcribed and translated from the JsFLS4 gene may have higher catalytic activity for dihydroquercetin. The above results indicate that the TRV-mediated VIGS system can be an ideal tool for studying J. sigillata gene function.

Visible light-induced C(sp3)-H azolation of ethers via radical-polar crossover.

Reported herein is a photochemical strategy for C(sp3)-H azolation of ethers via a hydrogen-atom transfer and radical-polar crossover process, offering efficient access to valuable N-alkylated azoles under visible-light irradiation. The protocol is metal-free and photocatalyst-free, and exhibits good to excellent yields and broad substrate scope with regard to azoles. EPR experiments provide evidence for the formation of intermediates formed in situ.

Heart-on-a-chip systems with tissue-specific functionalities for physiological, pathological, and pharmacological studies.

Recent advances in heart-on-a-chip systems hold great promise to facilitate cardiac physiological, pathological, and pharmacological studies. This review focuses on the development of heart-on-a-chip systems with tissue-specific functionalities. For one thing, the strategies for developing cardiac microtissues on heart-on-a-chip systems that closely mimic the structures and behaviors of the native heart are analyzed, including the imitation of cardiac structural and functional characteristics. For another, the development of techniques for real-time monitoring of biophysical and biochemical signals from cardiac microtissues on heart-on-a-chip systems is introduced, incorporating cardiac electrophysiological signals, contractile activity, and biomarkers. Furthermore, the applications of heart-on-a-chip systems in intelligent cardiac studies are discussed regarding physiological/pathological research and pharmacological assessment. Finally, the future development of heart-on-a-chip toward a higher level of systematization, integration, and maturation is proposed.

Direct C(sp3)-H Arylation of Unprotected Benzyl Anilines and Alkylarenes by Organocatalysis under Visible Light.

Reported herein is direct C(sp3)-H arylation of unprotected benzyl anilines and alkylarenes via consecutive photoinduced electron transfer by visible light irradiation. Reductive quenching cycles and radical-radical cross-coupling were involved, and electron paramagnetic resonance experiments provide evidence for the formation of radical intermediates formed in situ. The protocol highlights transition metal free, external oxidant free, broad substrate scope, and high efficiency (>60 examples, up to 96%).

A Metal-Free Molecular Ferroelectric [4-Me-cyclohexylamine]ClO4 Introduced by Boat and Chair Conformations of Cyclohexylamine.

Organic ferroelectrics have received a great deal of interest due to their exclusive properties. However, organic ferroelectrics have not been fully explored, which hinders their practical application. Here, we presented a novel metal-free organic molecular ferroelectric [4-MCHA][ClO4 ] (1) (4-MCHA=trans-4-methylcyclohexylamine), which exhibits an above-room-temperature of 328 K. Strikingly, the single crystal structure analysis of 1 shows that the driving force of phase transition is related to the interesting chair-boat conformation change of 4-MCHA cation, in addition to the order-disorder transition of ClO4 - anion. Using piezoelectric response force microscopy (PFM), the presence of domains and the implemented polarization switching were clearly observed, which explicitly determined the presence of room-temperature ferroelectricity of 1. As far as we know, the ferroelectric phase transition mechanism attributed to the conformational change in a trans isomeric cation is very rare. This research enriched the path of designing ferroelectric materials and smart materials.

Antimony Bromide Organic-Inorganic Hybrid Compound with a Long-Chain Diamine Showing Switchable Phase Transition and Second-Harmonic Generation Properties.

Organic-inorganic hybrid metal halides have attracted significant attention in recent years due to their excellent optoelectronic properties and potential applications in solar cells. Herein, the organic-inorganic hybrid molecule [N,N-dimethyl-1,3-propanediamine]SbBr5 (1) was synthesized by reacting a long-chain organic diamine N,N-dimethyl-1,3-propanediamine with SbBr3 as a metal halide precursor in HBr aqueous solution. Compound 1 possesses a one-dimensional chainlike structure with the second-harmonic generation switch and two continuous phase transitions above room temperature. The band gap of compound 1 is about 2.62 eV, exhibiting a semiconductive property, which may have important implications for the development of new optoelectronic devices.

Electrochemical Decarboxylative Alkoxy-alkoxycarbonylation of Alkenes.

A method is presented for decarboxylative alkoxy-alkoxycarbonylation of various alkenes with alcohols by electrochemical anodic oxidation of monopotassium ethyloxalate salts with good functional group compatibility. The reaction involves anodic oxidation to form an acyl radical, followed by addition to an olefin to yield a new alkyl radical, which is anodically oxidized to a carbon cation and captured by alcohols to afford ß-alkoxyalkanoates. Adding catalytic amounts of ammonium iodide enhanced the efficiency of the reactions.

Alkali Metal Organic-Inorganic Hybrid Compounds with Different Crystal Dimensions Show Phase-Transition, Dielectric, and SHG Properties Based on a Quasi-Spherical Amine (1S,4S)-2,5-Diazabicyclo[2.2.1]heptane.

Reactions of a chiral and quasi-spherical molecule [1S,4S-2,5-2.2.1-H2dabch]I2 (1) with alkali metal halide MX (M = Na, K, Cs; X = Cl, Br) at room temperature produced a series of organic-inorganic hybrid (OIH) materials [1S,4S-2,5-2.2.1-H2dabch]NaBr3 (2), [1S,4S-2,5-2.2.1-H2dabch]CsCl3·H2O (3) and [1S,4S-2,5-2.2.1-H2dabch]KBr3·H2O (4). The single-crystal X-ray diffraction analysis revealed that the organic-inorganic framework structures comprised of the templating ligand and alkali metal halides (NaBr, CsCl, KBr) displayed dimensions spanning from one-dimensional (1D) to three-dimensional (3D). Moreover, the results of both differential scanning calorimetry (DSC) and dielectric measurements demonstrated that compounds 1-4 displayed reversible, high-temperature phase transitions and noticeable dielectric anomalies. In addition, the temperature-dependent second harmonic generation (SHG) results revealed crystals 1 and 3 can switch from the SHG-ON to the SHG-OFF state, which was proved by the variable-temperature X-ray diffraction. This research aims to streamline the exploration of multifunctional second harmonic generation (SHG) and dielectric materials that have been synthesized using chiral ligands and alkali metals. This will provide researchers with enhanced opportunities to delve further into this specific research domain.

GRB7 plays a promoting role in the progression of gastric cancer.

BACKGROUND: Gastric cancer is a clinically common tumor, showing an upward trend of both incidence and mortality. GRB7 has been identified as a vital regulator in tumor progression. This study aims to uncover the biological function of GRB7 in gastric cancer process. METHODS: immunohistochemical (IHC) staining using a tissue microarray (TMA), quantitative reverse transcription PCR (qRT-PCR) and Western blotting were performed to detect the expression of genes. Furthermore, gastric cancer cell lines AGS and MGC-803 were transfected with short hairpin RNAs against GRB7. The biological function of GRB7 in gastric cancer cells were examined by CCK-8, flow cytometry, wound healing and Transwell assays. Then, in vivo tumor formation assay was conducted to explore the effects of GRB7 on tumor growth. Finally, expression levels of proteins related to cell functions were determined by Western blotting. Coimmunoprecipitation (CoIP) assay was performed to assess the protein-protein interaction. RESULTS: GRB7 was up-regulated in gastric cancer tissues and cell lines, and its expression was inversely proportional to survival of gastric cancer patients. Moreover, GRB7 knockdown inhibited proliferative, migratory abilities, as well as promoted cell apoptosis in gastric cancer cells. Further study suggested that GRB7 silencing could suppress gastric cancer tumor growth in vivo. Furthermore, our study uncovered an important interaction between GRB7 and MyD88. Silencing MyD88 was observed to alleviate the malignant phenotypes promoted by GRB7 in gastric cancer cells. CONCLUSIONS: Together, this study provided evidence that GRB7 may be an effective molecular targets for the treatment of gastric cancer.

An organic-inorganic hybrid material [Me3NCH2CH2F]FeBr4 exhibits three-step SHG on/off.

A novel solid-state second harmonic generation (SHG) organic-inorganic hybrid switch [Me3NCH2CH2F]FeBr4 (1) exhibits genuine three-step "on-off-on-off" SHG-switching above-room temperature, which has potential applications in multi-step optical devices.

Umpolung trifluoromethylthiolation of alcohols.

Herein we develop a metal-free umpolung dehydroxytrifluoromethylthiolation of alcohols with commercially available PPh3 and N-trifluoromethylthiophthalimide within 30 minutes. This protocol shows excellent functional group tolerance and high regioselectivity. The dehydroxytrifluoromethylthiolation of a series of natural products and drugs further demonstrates its practicality. Preliminary mechanistic studies suggest that PPh3 is responsible for deoxygenation and the key trifluoromethylthiophosphonium ion may be hydrolyzed by H2O in solvent.

Multifunctional Ni3S2@NF-based electrocatalysts for efficient and durable electrocatalytic water splitting.

Transition-metal sulfides (TMSs) have indeed drawn dramatic interest as a potential species of electrocatalysts by virtue of their unique structural features. However, their poor stability and inherent activity have impeded their use in electrocatalytic water splitting. Here, we provide a rational design of a hierarchical nanostructured electrocatalyst containing CeOx-decorated NiCo-layered double hydroxide (LDH) coupled with Ni3S2 protrusions formed on a Ni foam (NF). Specifically, the as-prepared electrocatalyst, denoted as Ni2Co1 LDH-CeOx/Ni3S2@NF, presents only 250 and 300 mV overpotential at ±100 mA cm-2, respectively, along with the Tafel slope values of 92 and 52 mV dec-1, as well remarkable long-term life for water splitting in an alkaline electrolyte. Based on systematic experiments and theoretical analysis, the superior electrocatalytic property in terms of Ni2Co1 LDH-CeOx/Ni3S2@NF can be imputed to the following reasons: the porous framework of Ni3S2@NF provides a largely surface area and high conductivity; the NiCo LDH nanosheets provide enriched active sites and favorable adsorption ability; the oxygen-vacancy-rich CeOx optimizes the electronic configuration. Overall, these factors work synergistically to expedite the catalytic kinetics of splitting water. Our work concentrates on a rational interface to devise efficient, multifunctional, and serviceable electrocatalysts for future applications.

Selective Cross-Dehydrogenative Coupling of Various Acyclic Enamides with Heteroarenes via Rh(III)-Catalyzed C-H Activation.

The developed methodology describes an efficient Rh(III)-catalyzed oxidative C-H/C-H cross-coupling between acyclic enamides and heteroarenes. This cross dehydrogenative coupling (CDC) reaction offers advantages, including excellent regioselectivity and stereoselectivity, good functional group compatibility, and a broad substrate scope. Mechanistically, Rh(III)-catalyzed ß-C(sp2)-H activation of acyclic enamides is proposed to be the critical step.