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In the pickling process and acidizing program for oil wells, the acidic corrosion of metals is a problem that needs to be addressed. Various acid corrosion inhibitors have been studied and used to mitigate the acidic corrosion of carbon steel. In this paper, the corrosion inhibition of 2‐aminobenzothiazole (2 N‐BT), 2‐amino‐4‐hydroxybenzothiazole (2 N4O‐BT), and 2‐amino‐6‐hydroxybenzothiazole (2 N6O‐BT) on carbon steel in 0.5 mol/L HCl was investigated using electrochemical and quantum chemical methods. All three molecules exhibited corrosion inhibition effects. Compared to 2 N‐BT, 2 N4O‐BT and 2 N6O‐BT showed less sensitivity to the environmental conditions and the surface state of the metal. Among them, 0.0010 mol/L 2 N6O‐BT demonstrated the highest and most persistent corrosion inhibition, exhibiting a mixed inhibition mechanism with cathodic inhibition dominance. The adsorption of 2 N6O‐BT on the carbon steel surface was found to be non‐uniform, preferentially adsorbing at certain active sites on the surface, following Freundlich‐Langmuir thermodynamic characteristics. It showed initial strongly adsorbed points and weakly adsorbed regions. With continued adsorption of 2 N6O‐BT, the differences between strongly adsorbed points and weakly adsorbed regions decreased. The introduction of hydroxyl groups, especially in 2 N6O‐BT, extended the negative potential region and enhanced the coordination activity of the molecule, generating the orbital distribution that was advantageous to flat adsorption and the formation of feedback bonds. This provided a molecular structural basis for the excellent corrosion inhibition properties of 2 N6O‐BT. [ABSTRACT FROM AUTHOR]

A copper‐catalyzed α,β‐regioselective (2+4) cycloaddition of propargylic esters with o‐hydroxyphenyl substituted secondary phosphine oxides (SPOs) was established, which afforded a series of phosphorus‐containing six‐membered heterocycles in high yields. This reaction represents the first α,β‐regioselective (2+n) cycloaddition of propargylic esters via the intermediates of copper‐allenylidenes, which will enrich the chemistry of propargylic esters and copper‐allenylidenes. Moreover, this work also represents the first application of o‐hydroxyphenyl substituted SPOs as 1,4‐dinucleophiles in (2+4) cycloadditions, which provides a useful protocol for the synthesis of phosphorus‐containing six‐membered heterocycles with potential bioactivity. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A photoelectrochemical approach for the C—H silylation of heteroarenes through dehydrogenation cross‐coupling with H2 evolution has been developed. The photoelectrochemical C—H silylation depends on hydrogen atom transfer (HAT) from silanes to Cl‐radical generated through the light‐induced homolytic cleavage of Cl2, in which Cl2 was produced by electrochemical oxidation of chloride. A large number of silylated heterocyclic molecules are rapidly constructed in satisfactory yields without relying on oxidants and metal reagents. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A photoelectrochemical approach for the C—H silylation of heteroarenes through dehydrogenation cross‐coupling with H2 evolution has been developed. The photoelectrochemical C—H silylation depends on hydrogen atom transfer (HAT) from silanes to Cl‐radical generated through the light‐induced homolytic cleavage of Cl2, in which Cl2 was produced by electrochemical oxidation of chloride. A large number of silylated heterocyclic molecules are rapidly constructed in satisfactory yields without relying on oxidants and metal reagents. [ABSTRACT FROM AUTHOR]

Spontaneous droplet jumping on micro‐/nano‐structured superhydrophobic surfaces has been exploited as an efficient means for enhancing steam condensation heat transfer. However, the good performance of such surfaces quickly decays with raising the degree of subcooling, due to the mismatch between the characteristic length scales and droplet sizes when they grow up. Herein, a novel strategy for multiscale droplet regulation is proposed by combining sub‐millimeter fin structure with a hierarchical microporous superhydrophobic surface. A superior condensation heat transfer performance is attained on such hierarchical superhydrophobic finned tube (F‐SHB), in comparison to the baseline case of superhydrophobic non‐finned (SHB) tube under well‐controlled test conditions. Although the droplet jumping is not as vigorous as that on the SHB tube, the finned geometry of the F‐SHB tube leads to a condensation heat transfer enhancement even under high degrees of subcooling up to 36 K, because of the accelerated departure of large droplets by imposing Laplace force gradient in the presence of V‐shaped sub‐millimeter fins. This multiscale enhancement strategy is shown to enable a cascading regulation over the entire lifespan of condensate droplets. The fabrication of F‐SHB tubes is facile and easy to be scaled up, showing great potential in practical steam condensation applications. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) is considered to mediate plant growth and development. However, whether H2S regulates the adaptation of mangrove plant to intertidal flooding habitats is not well understood. In this study, sodium hydrosulfide (NaHS) was used as an H2S donor to investigate the effect of H2S on the responses of mangrove plant Avicennia marina to waterlogging. The results showed that 24‐h waterlogging increased reactive oxygen species (ROS) and cell death in roots. Excessive mitochondrial ROS accumulation is highly oxidative and leads to mitochondrial structural and functional damage. However, the application of NaHS counteracted the oxidative damage caused by waterlogging. The mitochondrial ROS production was reduced by H2S through increasing the expressions of the alternative oxidase genes and increasing the proportion of alternative respiratory pathway in the total mitochondrial respiration. Secondly, H2S enhanced the capacity of the antioxidant system. Meanwhile, H2S induced Ca2+ influx and activated the expression of intracellular Ca2+‐sensing‐related genes. In addition, the alleviating effect of H2S on waterlogging can be reversed by Ca2+ chelator and Ca2+ channel blockers. In conclusion, this study provides the first evidence to explain the role of H2S in waterlogging adaptation in mangrove plants from the mitochondrial aspect. Summary statement: H2S reduces mitochondrial ROS production by increasing the expressions of the alternative oxidase gene (AOX) and increases the proportion of alternative respiratory pathway in the total respiration, while H2S alleviates the mitochondrial structural damages including loss of bilayer membranes and blurring of mitochondrial cristae, and functional damages such as decrease of mitochondrial membrane potential (ΔΨm), membrane permeability transition pores opening, Cyt c release and the blockage of electron transfer along the mitochondrial electron transport chain caused by waterlogging‐induced oxidative stress. Secondly, H2S enhances the capacity of the antioxidant system through upregulating the expression of SOD, CAT, and APX genes to scavenge excess ROS. Last, H2S induces Ca2+ influx in the roots under waterlogging. Our results provide the better understanding of the role of H2S in adaptation of mangrove plants to the coastal intertidal environment from the mitochondrial aspect. [ABSTRACT FROM AUTHOR]

This study establishes the first organocatalytic enantioselective synthesis of axially chiral N,N′‐bisindoles via chiral phosphoric acid‐catalyzed formal (3+2) cycloadditions of indole‐based enaminones as novel platform molecules with 2,3‐diketoesters, where de novo indole‐ring formation is involved. Using this new strategy, various axially chiral N,N′‐bisindoles were synthesized in good yields and with excellent enantioselectivities (up to 87 % yield and 96 % ee). More importantly, this class of axially chiral N,N′‐bisindoles exhibited some degree of cytotoxicity toward cancer cells and was derived into axially chiral phosphine ligands with high catalytic activity. This study provides a new strategy for enantioselective synthesis of axially chiral N,N′‐bisindoles using asymmetric organocatalysis and is the first to realize the applications of such scaffolds in medicinal chemistry and asymmetric catalysis. [ABSTRACT FROM AUTHOR]

By designing and using a new flexible bis(pyrimidine)‐bis(amide) ligand H2L [H2L=N,N′‐bis(4‐pyrimidinecarboxamido)‐1,3‐propane], two new polyoxometalate (POM)‐based metal‐organic complexes (MOCs), H3[Cu2(L)2(PMo12O40)] (1) and [Cu2(H2L)2(β‐Mo8O26)] (2), were synthesized under solvothermal and hydrothermal conditions, respectively. In complexes 1 and 2, metal‐organic units and POM anions are linked together to form two distinct 2D structures. The [PMo12O40]3− (PMo12) anions were used as μ4‐bridging ligands in complex 1 and linked the 1D [Cu(L)]n metal‐organic chains to form a 2D layered structure. The [β‐Mo8O26]4− (Mo8) anions adopted two diverse coordination modes in complex 2 and connected the 1D [Cu(H2L)]n2n+ metal‐organic chains to generate a 2D grid structure. Complexes 1–2 can serve as electrode materials of supercapacitor and show large specific capacitances, up to 1065 and 956 F g−1 at current density of 2 A g−1, respectively, which surpass the parent POM and most of the previous reported POM‐based electrode materials, thus demonstrating the important role of introducing metal‐organic units in improving capacitive performances. Besides, the electrocatalytic redox activities of complexes 1–2 were also studied, both of them can be used as electrochemical sensors to detect Cr(VI) ions. They possess high sensitivity of 0.537 and 0.455 μA μM−1 and low detection limits of 0.16 and 0.33 μM, which are below the maximum content of Cr(VI) in groundwater required by the WHO. [ABSTRACT FROM AUTHOR]

A Lewis acid‐catalyzed (3+2) cycloaddition of 2‐indolylmethanols with β,γ‐unsaturated α‐ketoesters was established, which afforded a series of cyclopenta[b]indoles in overall high yields (up to 98 %) with excellent diastereoselectivities (up to >95 : 5 dr). This reaction not only represents the first C3‐nucleophilic (3+2) cycloaddition of 2‐indolylmethanols, but also provides a good example for (2+n) cycloaddition of β,γ‐unsaturated α‐ketoesters, which will add new contents to the chemistry of 2‐indolylmethanols. In addition, this approach provides an atom‐economic and useful method for the construction of biologically important cyclopenta[b]indole scaffold. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A new strategy for the enantioselective synthesis of axially chiral 3,3'‐bisindoles was devised by the direct coupling of two indole rings. This strategy makes use of the C3‐umpolung reactivity of 2‐indolylmethanols, which enables the catalytic asymmetric addition reaction of 2‐indolylmethanols with rationally designed 2‐substituted indoles, thus constructing axially chiral 3,3'‐bisindole scaffolds in overall excellent yields (up to 98%) with high enantioselectivities (up to 96 : 4 er). This approach not only has overcome the challenges in constructing axially chiral five‐five‐membered heterobiaryls, but also represents a new application of the C3‐umpolung reactivity of 2‐indolylmethanols in asymmetric catalysis. More importantly, this class of axially chiral 3,3'‐bisindoles can undergo a variety of post‐functionalizations to give axially chiral 3,3'‐bisindole‐based organocatalysts, which have found their preliminary applications in asymmetric catalysis. [ABSTRACT FROM AUTHOR]

The first highly atroposelective construction of N−N axially chiral indole scaffolds was established via a new strategy of de novo ring formation. This strategy makes use of the organocatalytic asymmetric Paal–Knorr reaction of well‐designed N‐aminoindoles with 1,4‐diketones, thus affording N‐pyrrolylindoles in high yields and with excellent atroposelectivities (up to 98 % yield, 96 % ee). In addition, this strategy is applicable for the atroposelective synthesis of N−N axially chiral bispyrroles (up to 98 % yield, 97 % ee). More importantly, such N−N axially chiral heterocycles can be converted into chiral organocatalysts with applications in asymmetric catalysis, and some molecules display potent anticancer activity. This work not only provides a new strategy for the atroposelective synthesis of N−N axially chiral molecules but also offers new members of the N−N atropisomer family with promising applications in synthetic and medicinal chemistry. [ABSTRACT FROM AUTHOR]

A new class of axially chiral styrene‐based thiourea tertiary amine catalysts, which have unique characteristics such as an efficient synthetic route, multiple chiral elements, and multiple activating groups, has been rationally designed. These new chiral catalysts have proven to be efficient organocatalysts, enabling the chemo‐, diastereo‐, and enantioselective (2+4) cyclization of 2‐benzothiazolimines with homophthalic anhydrides in good yields (up to 96 %) with excellent stereoselectivities (all >95:5 dr, up to 98 % ee). More importantly, theoretical calculations elucidated the important role of an axially chiral styrene moiety in controlling both the reactivity and enantioselectivity. This work not only represents the first design of styrene‐based chiral thiourea tertiary amine catalysts and the first catalytic asymmetric (2+4) cyclization of 2‐benzothiazolimines, but also gives an in‐depth understanding of axially chiral styrene‐based organocatalysts. [ABSTRACT FROM AUTHOR]

A new Anderson‐type polyoxometalate(POM)‐based one‐dimensional metal‐organic complex, namely, H2[Cu2[AlMo6(OH)6O18]2(3‐bpah)4(H2O)4] ⋅ 6H2O (1) (3‐bpah=N−N′‐bis(3‐pyridinecarboxamide)‐1,2‐cyclohexane) was synthesized by hydrothermal method. Implement basic characterization operations of single crystal X‐ray diffraction, IR spectroscopy, X‐ray powder diffraction and thermogravimetric analysis were performed. Complex 1 possesses not only the typical electrochemical behavior of the Anderson‐type polyoxoanion, but also excellent electrochemical stability. The carbon paste electrode bulk modified by complex 1(1‐CPE) can be used as an ampere sensor to detect potassium nitrite. The carbon cloth‐based electrode fabricated by complex 1(1‐CC)was capable of being used as electrocatalyst for hydrogen evolution reaction, the overpotential is 480 mV at the current density of 10 mA cm−2. 1‐CC can also be used as capacitor electrode, which shows an area capacitance of 293 mF cm−2 in 0.1 M H2SO4 solution and up to 10 hours of life stability. It can maintain 89.7 % of the capacitance after 1000 cycles of constant current charge/discharge. [ABSTRACT FROM AUTHOR]

Summary: Patients with classical Hodgkin lymphoma (cHL) who do not achieve complete remission (CR) after second‐line chemotherapy have poor clinical outcomes. Besides, conventional salvage chemotherapy regimens have an unsatisfactory CR rate. The present retrospective study reports the efficacy and toxicity of the GVD (gemcitabine, vinorelbine, liposomal doxorubicin) regimen with or without programmed cell death 1 (PD‐1) inhibitor for patients with cHL who failed first‐line treatment. A total of 103 patients with cHL (GVD+PD‐1 group, n = 27; GVD group, n = 76) with response assessment based on positron emission tomography were included. The GVD+PD‐1 group tended to have a higher CR rate than GVD group (85·2% vs. 65·8%, P = 0·057) and had a better event‐free survival (EFS) (P = 0·034). Subgroup analysis showed that patients with low‐risk second‐line International Prognostic Score might benefit from the addition of PD‐1 inhibitor (GVD+PD‐1 vs. GVD, 100·0% vs. 64·7%, P = 0·028) and had better EFS than GVD alone (P = 0·016). Further analysis demonstrated that PD‐1 consolidation therapy might provide an EFS benefit (P = 0·007). The toxicity of the GVD+PD‐1 regimen was comparable to the GVD regimen, except for higher rates of hypothyroidism and autoimmune pneumonitis, which were manageable. In conclusion, combining a PD‐1 inhibitor with a GVD regimen could be a potentially effective second‐line therapy for patients with cHL. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Atroposelective construction of axially chiral alkene‐heteroaryl scaffolds is highly desired but challenging. In this work, we established an atroposelective construction of axially chiral alkene‐indole scaffolds via the strategy of catalytic enantioselective addition reaction of 3‐alkynyl‐2‐indolylmethanols with bulky nucleophiles. In this strategy, α‐amido sulfones were used as competent nucleophiles and chiral phosphoric acid (CPA) acted as suitable chiral catalyst for this addition reaction. By this strategy, a new class of axially chiral acyclic alkene‐indoles was synthesized in overall high yields (up to 86%), excellent (E/Z)‐selectivity (all > 95 : 5) and good enantioselectivities (up to 92 : 8 er). This reaction represents the first catalytic enantioselective construction of axially chiral alkene‐indole frameworks, which will add a new member to the family of atropoisomeric heterocycles, especially the family of axially chiral indole compounds. [ABSTRACT FROM AUTHOR]

Summary: We constructed a prognostic score for persons with diffuse large B‐cell lymphoma (DLBCL) based on infiltrating immune cells. Data of 956 consecutive subjects were retrieved from the Gene Expression Omnibus database and assigned to training (GSE10846, n = 305) or validation (GSE87371n = 206 and GSE117556n = 445 combined) cohorts. Proportions of non‐lymphoma cells in the sample were inferred using the ESTIMATE algorithm. An immune risk score was constructed comprised of eight types of non‐lymphoma immune cells calculated using the CIBERSORT algorithm. Five‐year survival of subjects with an immune risk score ≤ 0·45 in the training cohort was better than that of subjects with a score > 0·45 (hazard ratio [HR] = 3·99; 95% confidence interval [CI] = 2·74, 5·82; P < 0·001). HR in the validation cohort was HR = 2·17 (1·47, 3·21; P < 0·001). Enrichment analyses indicated correlations with genes controlling immune‐related biological processes and pathways. A nomogram comprised of the immune risk score and most covariates including age, lactate dehydrogenase concentration (LDH), lymphoma‐type (germinal centre B cell [GCB] versus non‐GCB), Eastern Cooperative Oncology Group performance status (ECOG‐PS) and rituximab therapy had a C‐statistic of 0·76 compared with C‐statistics of 0·69 and 0·69 for the International Prognostic Index (IPI) and Revised International Prognostic Index (R‐IPI). These data indicate the immune risk score is an accurate, independent survival predictor in persons with DLBCL. [ABSTRACT FROM AUTHOR]

The regio‐ and enantioselective (3+3) cycloaddition of nitrones with 2‐indolylmethanols was accomplished by the cooperative catalysis of hexafluoroisopropanol (HFIP) and chiral phosphoric acid (CPA). Using this approach, a series of indole‐fused six‐membered heterocycles were synthesized in high yields (up to 98 %), with excellent enantioselectivities (up to 96 % ee) and exclusive regiospecificity. This approach enabled not only the first organocatalytic asymmetric (3+3) cycloaddition of nitrones but also the first C3‐nucleophilic asymmetric (3+3) cycloaddition of 2‐indolylmethanols. More importantly, theoretical calculations elucidated the role of the cocatalyst HFIP in helping CPA control the reactivity and enantioselectivity of the reaction, demonstrating a new mode of cooperative catalysis. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: A new class of indole‐based allylic donors have been designed and developed for palladium‐catalyzed decarboxylative allylations. In addition, the first application of these indole‐based allylic donors in palladium‐catalyzed decarboxylative [3+2] cycloaddition and allylic amination has been achieved by reacting with isocyanates and sulfonyl amines, respectively. This approach represents the first design of indole‐based allylic donors, which is helpful for settling the challenge of designing and developing new class of heterocycle‐based allylic donors for Pd‐catalyzed decarboxylative allylation reactions. Moreover, the application of this new class of allylic donors in cycloadditions and substitutions will add new contents to the research field of decarboxylative allylation. [ABSTRACT FROM AUTHOR]

The first metal‐catalyzed C3‐nucleophilic (4+3) cyclization of 2‐indolylmethanols with stable ortho‐quinone methides has been established, which constructed indole‐based seven‐membered heterocycles in high yields (70 %‐98 %) with regiospecificity. This reaction has tackled the challenges in exploring the C3‐nucleophilicity of 2‐indolylmethanols, which will contribute to the chemistry of 2‐indolylmethanols, especially to metal‐catalyzed cyclizations of 2‐indolylmethanols. In addition, this approach will provide a useful method for constructing indole‐based seven‐membered heterocycles with high efficiency and regioselectivity. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: A new class of axially chiral aryl‐alkene‐indole frameworks have been designed, and the first catalytic asymmetric construction of such scaffolds has been established by the strategy of organocatalytic (Z/E)‐selective and enantioselective (4+3) cyclization of 3‐alkynyl‐2‐indolylmethanols with 2‐naphthols or phenols (all >95 : 5 E/Z, up to 98% yield, 97% ee). This reaction also represents the first catalytic asymmetric construction of axially chiral alkene‐heteroaryl scaffolds, which will add a new member to the atropisomeric family. This approach has not only confronted the great challenges in constructing axially chiral alkene‐heteroaryl scaffolds but also provided a powerful strategy for the enantioselective construction of axially chiral aryl‐alkene‐indole frameworks. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: An atroposelective synthesis of a new class of 3,3'‐bisindoles bearing axial and central chirality has been established via catalytic asymmetric addition reactions using isatin‐derived imines as electrophiles (23 examples, up to 80% yield, > 95 : 5 dr, 98 : 2 er). This approach takes advantage of chiral phosphoric acid‐catalyzed dynamic kinetic resolution of 2‐substituted 3,3'‐bisindoles via nucleophilic addition of such substrates with isatin‐derived imines. In this approach, isatin‐derived imines acted as a class of competent electrophiles due to their high reactivity and bulky size, which provided an easy access to axially chiral 3,3'‐bisindoles incorporated with a biologically important chiral 3‐aminooxindole unit. This approach has greatly expanded the generality and applicability of the strategy of dynamic kinetic resolution for the synthesis of enantioenriched 3,3'‐bisindole derivatives bearing both axial and central chirality. [ABSTRACT FROM AUTHOR]

A new strategy for enantioselective synthesis of axially chiral naphthyl‐indoles has been established through catalytic asymmetric addition reactions of racemic naphthyl‐indoles with bulky electrophiles. Under chiral phosphoric acid catalysis, azodicarboxylates and o‐hydroxybenzyl alcohols served as bulky but reactive electrophiles that were attacked by C2‐unsubstituted naphthyl‐indoles, which underwent a dynamic kinetic resolution to afford two series of axially chiral naphthyl‐indoles in good yields (up to 98 %) and high enantioselectivities (up to 98:2 er). [ABSTRACT FROM AUTHOR]

Following the end Ordovician mass extinction, brachiopod faunas were commonly of low diversity, generally rare in abundance, and restricted to shallow‐water environments in many places. The Cathaysiorthis fauna, first described from South East China, is the most diverse brachiopod fauna in the world succeeding the Hirnantia fauna, and has modified our previous views on the recovery of shelly benthos after the extinctions. Here, we report a newly‐discovered fauna with abundant Cathaysiorthis from the lower Zhangwan Formation (lower–middle Rhuddanian, lower Llandovery) in Qinling, Xichuan County, Henan Province, China. This fauna is slightly younger than that previously documented from South East China, and the evolution of Cathaysiorthis fauna, in terms of its composition, is discussed. The Qinling Cathaysiorthis fauna has a narrower bathymetric range (Benthic Assemblage Zone 3) than that of the fauna from South East China (BA 2–5) and occurred on the Qinling–Dabie Microplate located on the northwest margin of the South China Plate. The migration of the Cathaysiorthis fauna from the South China plate to Qinling–Dabie was achieved by larvae that used ambient ocean currents and possibly drifted from the Jiangnan Region of South East China to Qinling. The Qinling Cathaysiorthis fauna includes 13 species belonging to 12 genera. Two new species, Cathaysiorthis xichuanensis sp. nov. and Aegiria apta sp. nov. are established and described herein, and ten other species are discussed. [ABSTRACT FROM AUTHOR]

The first catalytic asymmetric construction of the cyclic enaminone-based 3-substituted 3-amino-2-oxindole scaffold with potential bioactivity has been developed via chiral phosphoric acid-catalyzed enantioselective addition reactions of cyclic enaminones to isatin-derived imines, which afforded a series of cyclic enaminone-based 3-substituted 3-amino-2-oxindoles in high yields and excellent enantioselectivities (up to 99% yield, 97% ee). The investigation of the reaction mechanism suggested that it was facilitated by a dual hydrogen-bonding activation mode between the two substrates and the chiral phosphoric acid. Besides, this method could be utilized for a large-scale synthesis with maintained enantioselectivity. This approach will not only offer a useful method for enantioselective construction of the cyclic enaminone-based 3-substituted 3-amino-2-oxindole scaffold, but also enrich the research on catalytic asymmetric addition reactions of isatin-derived imines by using electron-rich olefins as nucleophiles. More importantly, a preliminary evaluation on the cytotoxicity of some selected products revealed that two of the enantio-pure compounds exhibited moderate to strong cytotoxicity to A549, 786-0, ECA109 and BT474 cancer cell lines. [ABSTRACT FROM AUTHOR]

An organocatalytic asymmetric approach has been developed for the ennantioselective construction of dihydroisocoumarin-based spirooxindole frameworks in high yields, excellent diastereo- and enantioselectivities (up to 99%, all >95:5 dr, up to 99% ee). This approach takes advantage of chiral thiourea-tertiaryamine catalyzed tandem reaction of isatins with enolizable homophthalic anhydride, which has wide substrate scope and can be performed with low catalyst loading. This reaction not only provides an efficient and useful method for constructing enantioenriched dihydroisocoumarin-based spirooxindole scaffold, but also will enrich the research contents of catalytic asymmetric tandem reactions and enantioselective synthesis of biologically important spirooxindoles. [ABSTRACT FROM AUTHOR]

The first catalytic asymmetric aminolysis of azlactones was achieved, enabling the highly enantioselective dynamic kinetic resolution of azlactones. This was demonstrated to be an efficient method for synthesizing optically pure bisamides in high yield with excellent enantioselectivity (up to 99 % yield, 99 % ee). The rational design of the amine nucleophile bearing both a sterically bulky group and an activating group was shown to be a key factor in attaining excellent enantioselectivity in the catalytic asymmetric aminolysis of azlactones. This approach not only provides easy access to biologically important enantiopure bisamides, but also enables the dynamic kinetic resolution of azlactones by using a strategy of enantioselective aminolysis, which was previously unknown in this research field. [ABSTRACT FROM AUTHOR]

An organocatalytic metal-free strategy has been established for the synthesis of pharmaceutically relevant meta-indolylanilines in generally excellent yields (up to 99 %). This strategy took advantage of the reaction of indoles and quinone imine ketals (QIKs) in the presence of racemic phosphoric acid, which proceeded via a 1,4-addition/alcohol elimination reaction sequence. The control experiment demonstrated that the dual hydrogen-bonding activation mode of the catalyst to the substrates played a crucial role in the reaction. This protocol provides a metal-free and step-economical approach to meta-anilines bearing either 3-indolyl or 2-indolyl moiety, which is of high value for the synthesis of compounds with potential bioactivities. [ABSTRACT FROM AUTHOR]

The organocatalytic asymmetric arylative dearomatization of indoles was achieved through two tandem approaches involving 2,3-disubstituted indoles and quinone imine ketals. One approach utilized the enantioselective cascade 1,4 addition/alcohol elimination reaction, the other employed the one-pot tandem arylative dearomatization/transfer hydrogenation sequence. In both cases, enantiomerically pure indole derivatives that bear an all-carbon quaternary stereogenic center were generated in high yields and excellent stereoselectivities (all d.r.>95:5, up to 99 % ee). [ABSTRACT FROM AUTHOR]

The C1 lateral mass screw technique is widely used for atlantoaxial fixation. However, C2 nerve dysfunction may occur as a complication of this procedure, compromising the quality of life of affected patients. This is a review of the topic of C2 nerve dysfunction associated with C1 lateral mass screw fixation and related research developments. The C2 nerve root is located in the space bordered superiorly by the posterior arch of C1, inferiorly by the C2 lamina, anteriorly by the lateral atlantoaxial joint capsule, and posteriorly by the anterior edge of the ligamentum flavum. Some surgeons suggest cutting the C2 nerve root during C1 lateral mass screw placement, whereas others prefer to preserve it. The incidence, clinical manifestations, causes, management, and prevention of C2 nerve dysfunction associated with C1 lateral mass screw fixation are reviewed. Sacrifice of the C2 nerve root carries a high risk of postoperative numbness, whereas postoperative nerve dysfunction can occur when it has been preserved. Many surgeons have been working hard on minimizing the risk of postoperative C2 nerve dysfunction associated with C1 lateral mass screw fixation. [ABSTRACT FROM AUTHOR]

The scalable title reaction between 2-arylidene-2-aryloxazol-5(4H)-ones and cyclohexane-1,3-diones to biologically important hexahydrocoumarins is described. [ABSTRACT FROM AUTHOR]

The front cover picture, provided by the group of Feng Shi from Jiangsu Normal University, illustrates the first catalytic asymmetric construction of cyclic enaminone ‐ based 3 ‐ amino ‐ 2 ‐ oxindole scaffolds with potential bioactivity via chiral phosphoric acid ‐ catalyzed enantioselective addition reactions of cyclic enaminones to isatin ‐ derived imines. The preliminary evaluation on the cytotoxicity of some selected products revealed that these enantioenriched compounds exhibited moderate to strong cytotoxicity to A549, 786 ‐ 0, ECA109 and BT474 cancer cell lines. The cover picture shows how their idea came out from this beautiful university. Details can be found in the Full Paper on pages 3069 – 3083 (L. ‐ J. Zhou, Y. ‐ C. Zhang, F. Jiang, G. He, J. Yan, H. Lu, S. Zhang, F. Shi, Adv. Synth. Catal. 2016, 358, 3069 – 3083; DOI: 10.1002/adsc.201600508). [ABSTRACT FROM AUTHOR]

A diagram is presented showing tryptamines catalytic asymmetric cascade dearomatization with indol-3-ylmethanols.

A new cooperative catalytic system consisting of a chiral phosphoric acid and a chiral guanidine is used for the title cycloaddition to give access to biological important dihydrocoumarin scaffolds. [ABSTRACT FROM AUTHOR]

A highly E- and enantioselective cyclization of o-hydroxybenzyl alcohols of type (I) and (IV) with dimedone derived enaminones is developed using a BINOL-derived phosphonic acid as organocatalyst. [ABSTRACT FROM AUTHOR]

An abstract of the article "Organocatalytic Reactions of Indoles with Quinone Imine Ketals: An Alternative Metal-Free Approach to Bioactive meta-Indolylanilines" by F. Jiang and colleagues is presented.

Arylative dearomatization of indoles in presence of chiral BINOL-derived phosphate TBP gives 3-aryl-3H-indoles with quaternary stereocenters in high yields with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

An abstract of the article "Organocatalytic Arylation of 3-Indolylmethanols via Chemo- and Regiospecific C6-Functionalization of Indoles" is presented.

Main observation and conclusion: Atroposelective construction of axially chiral alkene‐heteroaryl scaffolds is highly desired but challenging. In this work, we established an atroposelective construction of axially chiral alkene‐indole scaffolds via the strategy of catalytic enantioselective addition reaction of 3‐alkynyl‐2‐indolylmethanols with bulky nucleophiles. In this strategy, α‐amido sulfones were used as competent nucleophiles and chiral phosphoric acid (CPA) acted as suitable chiral catalyst for this addition reaction. By this strategy, a new class of axially chiral acyclic alkene‐indoles was synthesized in overall high yields (up to 86%), excellent (E/Z)‐selectivity (all > 95 : 5) and good enantioselectivities (up to 92 : 8 er). This reaction represents the first catalytic enantioselective construction of axially chiral alkene‐indole frameworks, which will add a new member to the family of atropoisomeric heterocycles, especially the family of axially chiral indole compounds. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: A new class of indole‐based allylic donors have been designed and developed for palladium‐catalyzed decarboxylative allylations. In addition, the first application of these indole‐based allylic donors in palladium‐catalyzed decarboxylative [3+2] cycloaddition and allylic amination has been achieved by reacting with isocyanates and sulfonyl amines, respectively. This approach represents the first design of indole‐based allylic donors, which is helpful for settling the challenge of designing and developing new class of heterocycle‐based allylic donors for Pd‐catalyzed decarboxylative allylation reactions. Moreover, the application of this new class of allylic donors in cycloadditions and substitutions will add new contents to the research field of decarboxylative allylation. [ABSTRACT FROM AUTHOR]