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The heavy difficulty faced by released juvenile delinquents of resocialization and the risk of destroying social order plague individual happiness and social harmony. It is of great significance to promote resocialization for the healthy development of the individual released juvenile delinquent and the harmony and stability of society. Through the literature research method, the author defines the concept of juvenile delinquency, clarifies the research scope of this paper, and studies and analyzes the different types of stigmatization of juvenile delinquency and the different levels of support needed in the process of socialization. Finally, the study found that released juvenile delinquents are negatively affected by the three levels of stereotype, prejudice and discrimination, which seriously hinders the integration of released juvenile delinquents into society, that is, resocialization. In the process of the resocialization of released juvenile delinquents, the support provided by the three levels of family, society and personal psychology plays an almost decisive role. Based on the above findings, the following recommendations are made: 1. Establish a social acceptance mechanism for released juvenile delinquents. 2. Build a family perception of the identity acceptance of released juvenile delinquents. 3. Enhance the emotional openness of released juvenile delinquents.

Due to their low reactivity, difficult enantiocontrol, and proneness to N-O bond cleavage, the catalytic asymmetric hydrogenation of oximes to hydroxylamines has remained a significant challenge. Herein, a Lewis and Brønsted acid cooperation strategy was established for the asymmetric hydrogenation of oximes, providing the corresponding hydroxylamines with up to 95% yield and up to 96% ee. Addition of Lewis and Brønsted acid was crucial to obtain high conversion and enantioselectivity. Mechanistic investigations indicates that the thiourea fragment of the ligand, Lewis acid (In(OTf)

An asymmetric organocatalytic remote 1,10-addition of alkynyl indole imine methides generated

Converting commercially available and affordable chiral sulfinamides to pharmaceutically important chiral sulfoximines via SIV-functionalization is synthetically appealing, however, remains little developed due to the competing N-functionalization pathway. To address this challenge, we disclose a strain-enabled stereospecific and chemoselective S-arylation and S-alkenylation of sulfinamides using arynes and cyclic alkynes. The origin of high SIV-selectivity is elucidated by density functional theory (DFT) calculations, which reveals the potential involvement of a novel concerted mechanism. This method affords unprecedented chemical diversity on groups attached to the nitrogen center (N-R) that is valuable for diversity-oriented drug discovery

A new C2h phase of 2D group III monochalcogenides with excellent electronic properties is computationally predicted and explored.

A rare hetero-ene mechanism has been computationally elucidated to enable the activation of unactivated alkenes by moderately strong chiral N-triflylphosphoramide Brønsted acid catalysts.

Competition between different types of electronic effects (charge versus π–π stacking) controls the regioselectivity of Rh-catalyzed [2 + 2 + 2] cycloaddition.

The installation of (benzo)thiophene-containing biaryls via coupling reactions has become a staple in designing photoelectric materials. Undeniably, C-H/C-H cross-coupling reactions between two (hetero)aromatics would be a shortcut toward these structural fragments. While more reliable cross-coupling technologies are well-established to provide C2-arylated (benzo)thiophenes, efficient methods that arylate the C3-position remain underdeveloped. Herein we provide insight into the factors that determine regioselectivity switching for these cross-coupling reactions. X-ray crystallographic analysis gives solid evidence for the key roles of triflate in regioselective dearomatization and acetate in base-assisted anti-β-deprotonated rearomatization. The first isolation and X-ray characterization of a medium-sized dearomatized cyclometalated adduct involving both substrates provide extra insight into aerobic oxidative Ar-H/Ar-H cross-coupling reactions. The mechanistic breakthrough incubates the first example, enabling C-H/C-H-type C3-arylation of benzothiophenes. Finally, this chemistry is used to design blue-emitting thermally activated delayed fluorescence (TADF) materials with a helicene conformation that exhibit a high maximum external quantum efficiency of 25.4% in OLED.

Diaryl ethers are widespread in biologically active compounds, ligands and catalysts. It is known that the diaryl ether skeleton may exhibit atropisomerism when both aryl rings are unsymmetrically substituted by steric hindered groups. Despite recent advances, only a very few catalytic asymmetric methods have been developed to construct such kind of axially chiral compounds. We described herein a dynamic kinetic resolution approach to axially chiral diaryl ethers via Brønsted acid catalyzed atroposelective transfer hydrogenation (ATH) reaction of dicarbaldehydes with anilines. The desired diaryl ethers could be obtained in moderate to good chemical yields (up to 79%) and high enantioselectivities (up to 95% ee) under standard reaction conditions. Such structural motifs are interesting precursors for further transformations and may have potential applications in synthesis of chiral ligands or catalysts.

The application of Suzuki-Miyaura coupling reaction to forge the atropisomeric biaryls has seen remarkable progress but exploration of this chemistry to directly forge chiral C(aryl)-C(alkene) axis is underdeveloped. The replacement of arene substrates by alkenes intensifies the challenges in terms of reactivity, configurational atropostability of product and selectivity control. By meticulous ligand design and fine-tuning of reaction parameters, we identified a highly active 3,3'-triphenylsilyl-substituted phosphite ligand to realize arene-alkene Suzuki-Miyaura coupling of hindered aryl halides and vinyl boronates under very mild conditions. The axially chiral acyclic aryl-alkenes were generated in commendable efficiency, enantioselectivity and E/Z selectivity.

We report herein a rare example of enantiodivergent aldehyde addition with β-alkenyl allylic boronates via chiral Brønsted acid catalysis. 2,6-Di-9-anthracenyl-substituted chiral phosphoric acid-catalyzed asymmetric allylation using β-vinyl substituted allylic boronate gave alcohols with R absolute configuration. The sense of asymmetric induction of the catalyst in these reactions is opposite to those in prior reports. Moreover, in the presence of the same acid catalyst, the reactions with β-2-propenyl substituted allylic boronate generated homoallylic alcohol products with S absolute configuration. Unusual substrate-catalyst C-H⋅⋅⋅π interactions in the favoured reaction transition state were identified as the origins of observed enantiodivergence through DFT computational studies.

A novel formal cross-coupling of aryl methyl sulfones and alcohols affording alkyl aryl ethers via an SRN1 pathway is developed. Two marketed antitubercular drugs were efficiently prepared employing this approach as the key step. A dimsyl-anion initiated radical chain process was revealed as the major pathway. DFT calculations indicate that the formation of a radical anion via nucleophilic addition of alkoxide to the aryl radical is the key step in determining the observed chemoselectivity.

Signaling complexes are often organized in a spatiotemporal manner and on a minute timescale. Proximity labeling based on engineered ascorbate peroxidase APEX2 pioneered in situ capture of spatiotemporal membrane protein complexes in living cells, but its application to cytosolic proteins remains limited due to the high labeling background. Here, we develop proximity labeling probes with increased labeling selectivity. These probes, in combination with label-free quantitative proteomics, allow exploring cytosolic protein assemblies such as phosphotyrosine-mediated protein complexes formed in response to minute-scale EGF stimulation. As proof-of-concept, we systematically profile the spatiotemporal interactome of the EGFR signaling component STS1. For STS1 core complexes, our proximity proteomics approach shows comparable performance to affinity purification-mass spectrometry-based temporal interactome profiling, while also capturing additional—especially endosomally-located—protein complexes. In summary, we provide a generic approach for exploring the interactome of mobile cytosolic proteins in living cells at a temporal resolution of minutes., APEX-based proximity labeling allows capturing protein interaction dynamics but its high labeling background limits its utility for cytosolic proteins. Here, the authors develop more selective proximity labeling probes, enabling the APEX-based characterization of time-resolved cytosolic protein interactomes.

We studied the mechanisms of activation and stereoselectivity of a monofunctional Diels-Alderase (PyrI4)-catalyzed intramolecular Diels-Alder reaction that leads to formation of the key spiro-tetramate moiety in the biosynthesis of the pyrroindomycin family of natural products. Key activation effects of PyrI4 include acid catalysis and an induced-fit mechanism that cooperate with the unique "lid" feature of PyrI4 to stabilize the Diels-Alder transition state. PyrI4 enhances the intrinsic Diels-Alder stereoselectivity of the substrate and leads to stereospecific formation of the product.

Although photothermal immunotherapy (PTI) is a compelling strategy for tumor therapy, the development of promising photothermal agents to overcome the insufficient immunogenicity of tumor cells and the poor immune response encountered in PTI is still challenging. Herein, commercial small-molecule-based organic metal adjuvants (OMAs) are presented, with second near-infrared photoacoustic and photothermal properties as well as the ability to perturb redox homeostasis to potentiate immunogenicity and immune responsiveness. OMAs, assembled from charge-transfer complexes and characterized by a broad substrate scope, high accessibility, and flexibly tuned optical properties, demonstrate strong phototherapeutic and adjuvant abilities via the depletion of glutathione and cysteine, and subsequently elicit systemic immunity by evoking immunogenic cell death, promoting dendritic cell maturation, and increasing T cell infiltration. Furthermore, programmed cell death protein 1 antibody can be employed to synergize with OMAs to suppress tumor immune evasion and ultimately improve the treatment outcomes. This study unlocks new paradigms to provide a versatile OMA-based scaffold for future practical applications. Agency for Science, Technology and Research (A*STAR) National Research Foundation (NRF) Submitted/Accepted version This work was supported by the National Natural Science Foundation of China (21972047), Guangdong Provincial Pearl River Talents Program (2019QN01Y314), Program for Guangdong Introducing Innovative and Entrepreneurial Teams (2019ZT08Y318), Natural Science Foundation of Guangdong Province China (2021A1515010724), China Postdoctoral Science Foundation (2021M691063), Fundamental Research Funds for the Central Universities of China, Singapore Agency for Science, Technology and Research (A*STAR) AME IRG grant (A20E5c0081), and Singapore National Research Foundation Investigatorship (NRF-NRFI2018-03).

Despite the enormous developments of asymmetric catalysis, the basis for asymmetric induction is largely limited to spatial interaction between substrate and catalyst. Consequently, asymmetric discrimination between two sterically similar groups remains a challenge. This is particularly formidable for enantiodifferentiation between aryl and heteroaryl groups without a directing group or electronic manipulation. Here we address this challenge by a robust organocatalytic system leading to excellent enantioselection between aryl and heteroaryl groups. With the versatile 2-indole imine methide as platform, an excellent combination of a superb chiral phosphoric acid and the optimal hydride source provided efficient access to a range of highly enantioenriched indole-containing triarylmethanes. Control experiments and kinetic studies provided important insights into the mechanism. DFT calculations also indicated that, while hydrogen bonding is important for activation, the key interaction for discrimination of the two aryl groups is mainly π-π stacking. Preliminary biological studies also demonstrated the great potential of these triarylmethanes for anticancer and antiviral drug development.

Computations and experiments leading to new chiral phosphoric acids (CPAs) for epoxide thionations are reported. Density functional theory calculations reveal the mechanism and origin of the enantioselectivity of such CPA-catalyzed epoxide thionations. The calculated mechanistic information was used to design new efficient CPAs that were tested experimentally and found to be highly effective. Bulky ortho-substituents on the 3,3'-aryl groups of the CPA are important to restrict the position of the epoxide in the key transition states for the enantioselectivity-determining step. Larger para-substituents significantly improve the enantioselectivity of the reaction.

The aim of this study was to investigate the role of the insulin-like growth factor-1 receptor (IGF-1R)Rats were divided into four groups. The sham group received sham operation and a single intraperitoneal administration of vehicle. The ovariectomy (OVX) group was subjected to bilateral OVX and vehicle injection. The streptozotocin (STZ) group received sham operation and a single STZ injection to induce hyperglycemia. The OVX + STZ group received bilateral OVX and a single STZ injection. Dual-energy X-ray absorptiometry measurement, bone biomechanics test, micro-computed tomography scan, and hematoxylin-eosin staining were performed to evaluate bone alteration in this model. The expression of relevant signals including IGF-1R, glycogen synthase kinase-3β (GSK-3β), and β-catenin were examined by quantitative real-time polymerase chain reaction and western blot.The OVX, STZ, and OVX + STZ groups induced bone loss, attenuated bone strength, and impaired microarchitecture compared with the sham group, respectively. Compared with OVX, more serious bone damage was found in the OVX + STZ group, which showed enhanced phosphorylation of IGF-1R, GSK-3β, and β-catenin.OVX plus STZ induced more serious bone impairment than OVX alone, which involves the IGF-1R/β-catenin signaling axis in the pathogenesis. This may provide a potential target for treatment of postmenopausal diabetic osteoporosis.

Summary Functionalization of arenes represents the most efficient approach for constructing a core backbone of important aryl compounds. Compared with the well-developed electrophilic aromatic substitution and transition-metal-catalyzed C–H activation, nucleophilic aromatic substitution remains challenging because of the lack of a convenient route for rapid conversion of the σH adduct to other stable and versatile intermediates in situ. Guided by computational design, we were able to realize asymmetric nucleophilic aromatic substitution by introducing a nitroso group on naphthalene via chiral phosphoric acid catalysis. This strategy enables efficient construction of atropisomeric indole-naphthalenes and indole-anilines with excellent stereocontrol. Density functional theory (DFT) calculations provide further insights into the origins of enantioselectivity and the reaction mechanisms. The successful application in the synthesis of NOBINs (2-amino-2′-hydroxy-1,1′-binaphthyl) extends the utility of this strategy.

A rhodium-catalyzed tandem enantioselective C-H silylation/alkene hydrosilylation of dihydrosilanes, which enables the streamlined construction of a wide range of silicon-stereogenic silanes, is successfully developed. This process involves a SiH2-steered highly enantioselective C-H silylation to furnish the corresponding desymmetric monohydrosilanes, which are subsequently trapped with alkenes in a stereospecific fashion to build functionally diverse asymmetrically tetrasubstituted silanes. This general strategy combines readily available dihydrosilanes and alkenes to construct various enantioenriched silicon-stereogenic silanes, including 9-silafluorenes, Si-bridged ladder compounds, and benzosilolometallocenes, in a single step with good to excellent yields and enantioselectivities.

A rational designed Ir(III)-catalyzed enantioselective C–H amidation of dibenzyl sulfoxides through desymmetrization and parallel kinetic resolution is demonstrated. An Ir(III) complex equipped wit...

A new chiral Brønsted acid, generated in situ from a chiral phosphoric acid boron (CPAB) complex and water, was successfully applied to asymmetric indole reduction. This "designer acid catalyst", which is more acidic than TsOH as suggested by DFT calculations, allows the unprecedented direct asymmetric reduction of C2-aryl-substituted N-unprotected indoles and features good to excellent enantioselectivities with broad functional group tolerance. DFT calculations and mechanistic experiments indicates that this reaction undergoes C3-protonation and hydride-transfer processes. Besides, bulky C2-alkyl-substituted N-unprotected indoles are also suitable for this system.