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An improved chemical process has been developed for the synthesis of (S , S)-DACH-Ph Trost ligand. The amidation of 2-diphenylphosphinylbenzoic acid and (S , S)-diaminocyclohexane is promoted by stoichiometric CDI and catalytic imidazole hydrochloride. The resulting product, (S , S)-DACH-Ph Trost ligand, is isolated as a white solid in 80% yield with >99% ee by simple filtration without column chromatography. The current facile process is also demonstrated on kilogram scale. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to compare the clinical effects of antibiotic calcium sulfate-loaded hybrid transport (ACSLHT) and traditional Ilizarov bone transport (TIBT) in the treatment of large tibial defects after trauma. Methods: Eighty-five patients with large tibial defects after trauma were selected for retrospective study. The range of tibial defects was 6–22 cm. After thorough debridement and infection controlled, bone transport technique was used to reconstruct tibial defects. Forty-four patients were treated with ACSLHT technique (the ACSLHT group), while the other 41 were treated with TIBT technique (the TIBT group). Time in external fixator was evaluated by EFI score. Enneking score was used to evaluate limb functions. SAS score was used to evaluate postoperative anxiety status. In addition, complication incidence was compared, including axis deviation, docking site nonunion, infection recurrence and so on. Results: There was no significant difference in preoperative general data between ACSLHT and TIBT group. EFI score in ACSLHT and TIBT group was 0.6 ± 0.1 cm/month and 1.7 ± 0.3 cm/month, respectively (P < 0.05). Enneking score of ACSLHT and TIBT group was 86.5% and 75.1% (P < 0.05). SAS score of ACSLHT group was significantly lower than that of TIBT group (P < 0.05). Complication incidence in ACSLHT group was significantly lower than that in TIBT group (P < 0.05). Conclusions: Compared with TIBT group, ACSLHT group had shorter time in external fixator, better limb functions, lower postoperative anxiety score and lower complication incidence which is worth of clinical promotion. [ABSTRACT FROM AUTHOR]

• IL-11 directly protects neuronal cells from oxidative damage caused by H 2 O 2 and reduces neuronal apoptosis. • Transcriptome analysis suggests that the JAK/STAT pathway may be involved in the antioxidant activity of IL-11. • Rescue experiments and animal models demonstrated that IL-11 prevented neuronal apoptosis caused by oxidative imbalance through activation of the JAK/STAT signaling pathway and promoted the recovery of motor function in SCI rats. Excess reactive oxygen species (ROS) generated by oxidative stress is a crucial factor affecting neuronal dysfunction after spinal cord injury (SCI). IL-11 has been reported to have antioxidative stress capacity. In the present study, we investigated the protective effect and mechanism of IL-11 against neuronal cell damage caused by oxidative imbalance. We established a H 2 O 2 -induced oxidative stress injury model in PC12 cells and observed the effects of IL-11 on cellular activity, morphology, oxidase and antioxidant enzymes, and ROS release. Furthermore, the effect of IL-11 on apoptosis of PC12 cells was assessed by flow cytometry, a TUNEL assay and Western blotting. Transcriptome analysis and rescue experiments revealed the mechanism by which IL-11 protects neurons from oxidative stress damage. For the in vivo investigation, an adenovirus-mediated IL-11 overexpression SCI rat model was constructed to validate the beneficial effect of IL-11 against SCI. IL-11 significantly improved the viability and enhanced the antioxidant activity of H 2 O 2 -treated PC12 cells while reducing ROS release. In addition, IL-11 reduced H 2 O 2 -induced PC12 cell apoptosis. Transcriptome analysis revealed that the JAK/STAT pathway may be related to the antioxidant activity of IL-11. Treatment with a JAK/STAT inhibitor (Stattic) exacerbated the oxidative damage induced by H 2 O 2 and attenuated the protective effects of IL-11. The results of in vivo studies showed that IL-11 prevented neuronal apoptosis due to oxidative imbalance and promoted the restoration of motor function in SCI rats by activating the JAK/STAT signaling pathway. IL-11 inhibited oxidative stress-induced neuronal apoptosis at least in part by activating the JAK/STAT signaling pathway and further promoted the recovery of motor function. These findings suggest that IL-11 may be an effective target for the treatment for SCI. [ABSTRACT FROM AUTHOR]

Overexpressed MMP-9 in vascular endothelial cells is involved in blood spinal cord barrier (BSCB) dysfunction in spinal cord injury (SCI). Esculentoside A (EsA) has anti-inflammatory and cell protective effects. This study aimed to evaluate its effects on neuromotor function in SCI rats, as well as the potential mechanisms. The therapeutic effect of EsA in SCI rats was investigated using Basso-Beattie-Bresnahan (BBB) scores, a grid walk test and histological analyses. To assess the protective role of EsA in the BSCB and in oxygen glucose deprivation/reoxygenation (OGD/R)-induced hBMECs, the BSCB function, tight junctions (TJ) protein (ZO-1 and claudin-5) expression, structure of the BSCB and Matrix metalloproteinase-9 (MMP-9) expression were observed via Evans blue (EB) detection, immunofluorescence analyses and western blotting. Molecular docking simulations and additional experiments were performed to explore the potential mechanisms by which EsA maintains the function of the BSCB in vivo and in vitro. EsA treatment improved BBB scores, reduced cavity formation and the loss of neuronal cells, demonstrating an improvement in motor function in SCI rats. In vivo experiments showed that EsA decreased the infiltration of blood cells and inflammatory mediators (IL-1β, IL-6 and TNF-α) and protected the structure of TJs in the rat spinal cord and in OGD/R-induced hBMECs. EsA inhibited the activation of Toll-like receptor 4 (TLR4) signalling, which may be related to the protective effect of EsA against MMP-9-induced BSCB damage. EsA downregulated MMP-9 expression in vascular endothelial cells, protected BSCB function in SCI rats and attenuated TLR4 signalling and thus provide new options for the treatment of SCI. • Esculentoside A treatment promoted the recovery of motor function in rats after SCI. • Esculentoside A treatment decreased the cytokine levels caused by increased BSCB permeability. • Esculentoside A protects the function of the BSCB by attenuating the expression of MMP-9 induced by TLR4 signalling. [ABSTRACT FROM AUTHOR]

Interaction between microplastics and soil is essential for the environmental fate of plastic particles. In this study, polystyrene microplastic particles (PSMPs) with a size of 0.047 μm were selected as the representative of microplastics. Five soil samples from different provinces in China were selected (named Harbin S1, Huainan S2, Jiangxi S3, Shaanxi S4 and Hainan S5, respectively) and their interaction characteristics and mechanism with PSMPs were investigated, which provided new insights into the environmental behavior of microplastics. The experimental data showed that the pseudo-first-order model well fit for the sorption kinetics data, and the microplastic sorption ability of the soil accorded with the following sequence: S3 > S2 > S1 > S4 > S5. The sorption isotherm data of PSMPs on soils fit a linear model well (R 2 = 0.998). The sorption of MPs on soils was affected by pH, and the sorption ability weakened as the pH increased. Soil physicochemical properties play important roles in sorption of PSMPs, especially the content of soil organic carbon. The sorption capacity was positively correlated with soil organic carbon (R 2 = 0.999) and Fe 2 O 3 content (R 2 = 0.967), while the sorption of clay showed opposite trend (R 2 = 0.952). The sorption mechanisms of PSMPs on soils included surface sorption, electrostatic and hydrophobic interactions. Results of this study could be useful to better study the role of soil in the fate and transportation of plastic particles. Unlabelled Image • The sorption of polystyrene microplastics (PSMPs) on five soils was investigated. • Soil organic carbon (SOC), clay and Fe 2 O 3 were vital in the sorption of PSMPs. • K d was positively correlated with SOC and Fe 2 O 3 , but negatively with clay content. • The sorption mechanism mainly included electrostatic and hydrophobic interaction. [ABSTRACT FROM AUTHOR]

As the power conversion efficiency (PCE) of perovskite solar cells (PSCs) is increased to as high over 25%, it becomes pre‐eminent to study a scalable process with wide processing window to fabricate large‐area uniform perovskite films with good light‐trapping performance. A stable and uniform intermediate‐state complex film is obtained by using tetramethylene sulfoxide (TMSO), which extends the annealing window to as long as 20 min, promotes the formation of a high‐quality perovskite film with larger grains (over 400 nm) and spontaneously forms the surface texture to result in an improved fill factor and open‐circuit voltage (Voc). Moreover, the superior surface texture significantly increases the long‐wavelength response, leading to an improved short‐circuit current density (Jsc). As a result, the maximum PCE of 21.14% is achieved based on a simple planar cell structure without any interface passivation. Moreover, a large area module with active area of 6.75 cm2 is assembled using the optimized TMSO process, showing efficiency as high as 16.57%. The study paves the way to the rational design of highly efficient PSCs for potential scaled‐up production. [ABSTRACT FROM AUTHOR]

• New class of P -stereogenic chiral N H Brønsted acid organocatalysts prepared. • Catalysts were prepared from chiral phosphinamides or secondary phosphine oxides. • Catalysts promoted the asymmetric reduction of quinolones by transfer hydrogenation. • Asymmetric transformation effected by the P -stereogenic chiral environment. • Easily tunable selectivity and reactivity by the substituents of phosphorous. A new class of N H Brønsted acid organocatalysts that feature P -stereogenic chirality was developed. These catalysts were prepared from P -stereogenic chiral phosphinamides and show similar reactivity to BINOL derived phosphoric acid toward the reduction of quinolines via transfer hydrogenation. It shows that stereoselectivity is induced by the P -chiral environment that is created by the substituents attached to the phosphorous atom, which can be readily tuned and modified. [ABSTRACT FROM AUTHOR]

P-Stereogenic chiral phosphine BI-BOP is employed for the first time as ligand to promote catalytic enantioselective synthesis of phosphoryl-substituted atropisomeric vinylarenes through a palladium−carbene pathway. This strategy utilizes 10 mol% palladium(II) acetate, 10 mol% phosphine ligand as well as a variety of N-tosylhydrazones and phosphoryl-substituted aryl bromides as the reaction partners. The desired axially chiral vinylarenes were isolated with up to 80% yield and 96:4 er, and can be further converted effectively and stereoselectively into dialkylphosphoryl-substituted atropisomeric arenes through a Grignard reaction. This protocol offers a general approach to synthesize phosphoryl-substituted atropisomeric vinylarenes with high enantiomeric purities. [ABSTRACT FROM AUTHOR]

Self-supervised visual representation learning focuses on capturing comprehensive features via exploiting the unlabeled datasets. However, existing contrastive learning based SSL frameworks are subjected to higher computational consumption and unsatisfactory performance. To handle these issues, we present a novel single-branch SSL method that incorporates an adaptive feature selection and activation module and a progressive cascade dimensionality reduction module, called APNet. Specifically, our method first fully exploits the unlabeled datasets and extracts intra- and inter-image information via introducing montage image. In addition, a novel adaptive feature selection and activation module is designed to generate the most comprehensive features. Besides, a progressive cascade dimensionality reduction module is proposed to capture the most representative features from latent vectors through cascade dimensionality increasing–decreasing operations. Extensive experiments have demonstrated the robustness and effectiveness of APNet. Specifically, APNet exceeds MoCo-v3 by 3.1% on the ImageNet-100 dataset, and consumes only half of the calculation. Code is available at https://github.com/AI-TYQ/APNet. • We embed feature selection and dimensionality reduction modules into SSL framework. • We design an attention module that selects and activates representative features. • We introduce a dimensionality reduction module to retain discriminative features. • We demonstrate the advantages of the above contributions through experiments. [Display omitted] [ABSTRACT FROM AUTHOR]

The effects of initial pressure on the self-acceleration characteristics of C1-C3 alkane flames were studied in a constant-volume chamber at an initial temperature of 400 K. The pressures of 0.25, 0.5, 1.0, and 1.5 MPa and the equivalence ratios of 0.8–1.6 were analyzed. Flame propagation images were recorded using high-speed Schlieren photography techniques. The self-accelerating exponent and fractal dimension of C1-C3 alkane flames were measured using the spherically expanding flame method and the Schlieren photography system. The results show that the self-acceleration exponent and fractal dimension of C1-C3 alkane flames increased with the increase in pressure, and the maximum values appeared when the pressure was 1.5 MPa. Furthermore, the evolution of the cellular structure in the flame front during self-acceleration was studied quantitatively. The wrinkling ratio λ=1.0635 can be used to determine the critical point at which the flame is completely cellular. It was found that under the same conditions, for a higher cellular instability of the flame, more cells split on the front surface of the same sized flame, and the cell density increases accordingly. However, the cell density does not increase indefinitely, and upon reaching a certain value, it does not change with the change in working conditions. • A constant-volume combustion test system and schlieren photography technology were used. • Self-accelerating exponent and fractal dimension of C1–C3 alkane-air premixed flames at elevated pressures were measured. • The wrinkling ratio was used to estimate the critical radius. • Qualitative and quantitative methods are used to analyze flame self-acceleration characteristics. [ABSTRACT FROM AUTHOR]

The use of chiral phosphinamides is relatively unexplored because of the lack of a general method for the synthesis. Reported herein is the development of a general, efficient, and highly enantioselective method for the synthesis of structurally diverse P-stereogenic phosphinamides. The method relies on nucleophilic substitution of a chiral phosphinate derived from the versatile chiral phosphinyl transfer agent 1,3,2-benzoxazaphosphinine-2-oxide. These chiral phosphinamides were utilized for the first synthesis of readily tunable P-stereogenic Lewis base organocatalysts, which were used successfully for highly enantioselective catalysis. [ABSTRACT FROM AUTHOR]

The cellular instabilities of premixed C1–C3 alkane–air mixtures were investigated at an initial temperature of 400 K and different initial pressures (0.25–1.5 MPa). Flame propagation images were recorded using high-speed Schlieren photography techniques. Cellular instabilities were analyzed using both qualitative and quantitative methods. The results showed that with an increase in the initial pressure, the flame instabilities of these three alkane–air mixtures increased as a result of the enhanced hydrodynamic instability. For a given initial pressure and with an increasing equivalence ratio, the thermal-diffusive instability was the main influencing factor on the flame instability of methane when Φ ≤ 1.0, whereas it was the result of hydrodynamic and thermal-diffusive instability when Φ > 1.0. The flame instability of ethane and propane was caused by the enhanced hydrodynamic and thermal-diffusive instability when Φ ≤ 1.0, whereas it was determined by diffusion-thermal instability when Φ > 1.0. Under the conditions with the strongest cellular instability, the cellular instability of these three alkane–air mixtures tended to increase with an increasing number of carbon atoms in the fuel. • Constant volume combustion vessel and schlieren photography techniques were used. • Flame instabilities of C1–C3 alkane–air premixed flames were investigated. • Critical Peclet number of the unstable flame was evaluated. • Cellular instabilities were analyzed using both qualitative and quantitative methods. [ABSTRACT FROM AUTHOR]

S-Alkyl,S-aryl, and S-vinyl thiosulfate sodium salts (Bunte salts)react with Grignard reagents to give sulfides in good yields. TheS-alkyl Bunte salts are prepared from odorless sodium thiosulfateby an SN2 reaction with alkyl halides. A Cu-catalyzed couplingof sodium thiosulfate with aryl and vinyl halides was developed toaccess S-aryl and S-vinyl Bunte salts. The reaction is amenable toa broad structural array of Bunte salts and Grignard reagents. Importantly,this route to sulfides avoids the use of malodorous thiol startingmaterials or byproducts. [ABSTRACT FROM AUTHOR]

A series of efficient ruthenium catalysts has been developed for the asymmetric hydrogenation and transfer hydrogenation of ketones with high reactivities and selectivities. The new chiral bisdihydrobenzooxaphosphole (BIBOP)/diamine-ruthenium complexes catalyzed the enantioselective hydrogenation of substrates such as aryl and heteroaryl cyclic and alkyl ketones with substrate/catalyst (S/C) ratios of up to 100,000. The opposite sense of enantioselectivity can be obtained by proper selection of a diamine with a given chirality of the phosphine. The usefulness of the new system has been demonstrated in the asymmetric hydrogenation of a complex synthetic intermediate towards cholesteryl ester transfer protein (CETP) inhibitors at S/C 20,000 on large-scale operation. [ABSTRACT FROM AUTHOR]

Is that SO? The title scaffolds have a highly active and properly differentiated SO bond for the efficient synthesis of enantiopure sulfinamides. The method is practical, green, and has the potential to provide an economical commercial process for the synthesis of bulky sulfinamides. [ABSTRACT FROM AUTHOR]

Ist das S ‐ O? Die im Titel bezeichneten Molekülgerüste verfügen über eine hoch aktive und ausreichend differenzierte S ‐ O ‐ Bindung für die effiziente Synthese enantiomerenreiner Sulfinamide. Die beschriebene Methode ist praktisch und umweltverträglich und könnte als Grundlage für ein ökonomisches kommerzielles Verfahren zur Herstellung sperriger Sulfinamide dienen. [ABSTRACT FROM AUTHOR]

A mild and general procedure for reduction of primary, secondary, and tertiary amides using catalytic triruthenium dodecacarbonyl and 1,1,3,3-tetramethyldisiloxane as reductant is described. The reaction is tolerant of numerous functional groups, and the amine products can often be isolated by direct crystallization as hydrochloride salts. The catalyst and silane are commercially available, air stable, and inexpensive, making the procedure accessible for both laboratory and large-scale applications. [ABSTRACT FROM AUTHOR]

Abstract: A mild method has been developed for the asymmetric synthesis of a variety of chiral diarylmethylamines via the addition of aryl Grignard reagents to chiral N-2,4,6-triisopropylbenzenesulfinylimines in high yields and high diastereoselectivities. Higher stereoselectivity was obtained for most of the examples studied when the reactions are performed at ambient temperature as compared to cryogenic conditions. N-2,4,6-Triisopropylbenzenesulfinamide was shown to be the optimal chiral auxiliary as it provided higher diastereoselectivities when compared to the more commonly employed tert-butanesulfinamide or p-toluenesulfinamide in the synthesis of diarylmethylamine synthons. A rationale for the improved selectivity derived from the triisopropylbenzyl auxiliary is presented. [Copyright &y& Elsevier]

Abstract: We describe the Ru-catalyzed ring-closing metathesis (RCM) reaction of a densely functionalized diene leading to the 15-membered ring of HCV protease inhibitor BILN 2061. The evaluation of several catalysts led us to the discovery of a new epimerization reaction which plagued our initial attempts to scale-up the reaction. A mechanistic study of this side reaction is described. Factors that may contribute to render our RCM sub-optimal were identified in the low initiation rate of the best catalyst (first-generation Hoveyda), to yield what seems to be a highly stabilized and perhaps catalytically inactive intermediate. Preliminary efforts to affect the initiation site by substrate modification are also discussed. [Copyright &y& Elsevier]

A multistep scalable synthesis of the clinically important hepatitis C virus (HCV) protease inhibitor BILN 2061 (1) is described. The synthesis is highly convergent and consists of two amide bond formations, one etherification, and one ring-closing metathesis (RCM) step, using readily available building blocks 2-5. The optimization of each step is described at length. The main focus of the paper is the study of the RCM step and the description of the main problems faced when scaling up to pilot scale this highly powerful but very challenging synthetic operation. Eventually, the RCM reaction was smoothly scaled up to produce >400 kg of cyclized product. [ABSTRACT FROM AUTHOR]

Abstract: Expedient and practical new methodology for the synthesis of substituted imidazoles was developed to provide a rapid access to a variety of 2-substituted, 1,2-disubstituted and 1,2,4-trisubstituted imidazoles by the direct CuCl-mediated reaction of nitriles with α-amino acetals in an intermolecular as well as intramolecular fashion. [Copyright &y& Elsevier]

Abstract: A streamlined and practical approach to 1H-imidazo[1,2-α]imidazol-2-one LFA-1 antagonist (1) that features as the key step a novel intramolecular boronic acid catalyzed cyclocondensation of a urea and an amide is reported. [Copyright &y& Elsevier]

A variety of Bunte salts react with Grignard reagents to give sulfides in good yields. [ABSTRACT FROM AUTHOR]

A mild and general protocol for the title reaction, which tolerates a wide range of functional groups is presented. [ABSTRACT FROM AUTHOR]