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Comprehensive Summary: Ten novel isocoumarins, including four pairs of enantiomers, were isolated from Artemisia dubia var. subdigitata (Asteraceae). Compounds 1, 2 and 3a/3b possessed a unique 6/6/6‐tricyclic system comprising an unusual 1‐(2‐methylcyclohexyl) propan‐1‐one moiety fused with isocoumarin core skeleton. Compounds 4a/4b were characterized as an unexpected 2,5‐dimethylcyclohexan‐1‐one scaffold, and compounds 5a/5b and 6a/6b were rare 1,2‐seco‐isocoumarin. Their structures and absolute configurations were elucidated through spectroscopic data, X‐ray crystallography, ECD and NMR calculations with DP4+ analyses. Plausible biosynthetic pathways were proposed from the naturally occurring isocoumarin. Network pharmacological analysis suggested that the targets of compound 1 were significantly enriched in the cell cycle and PI3K‐Akt signaling pathway. The molecular docking revealed that compound 1 had high binding affinity with CDK2 (total score: 6.8717). Furthermore, compounds 1 and 2 exhibited inhibitory activity on three human hepatoma cell lines, with inhibitory ratios of 85.1% and 84.5% (HepG2), 88.2% and 87.3% (Huh7), and 69.2% and 69.1% (SK‐Hep‐1) at 200 μmol·L–1, respectively. [ABSTRACT FROM AUTHOR]

A catalytic asymmetric vinylogous aldol reaction between β,γ-unsaturated amides and isatins has been developed. In the presence of 10 mol% of tertiary amine-thiourea C7, the vinylogous reaction has been achieved in up to 98% yield and up to 99% ee (26 examples). This methodology provides an efficient approach to construct chiral multifunctional 3-hydroxy-2-oxindoles. Moreover, the transformations of the chiral products, including the esterification of amides, the hydrogenation of the C–C double bond and further conversion to spirolactones, have been investigated. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Nineteen new cadinane‐involving sesquiterpenoid dimers, artemordins A—S (1—19), together with 13 known SDs (20—32) were isolated from Artemisia ordosica. Their structures and absolute configurations were established by comprehensive spectral analyses, X‐ray single crystal diffraction, theoretical ECD, and NMR calculations. Chemically, artemordins A—F (1—6) were the first examples of two cadinane units constructed by unprecedented C‐3−C‐15′ or C‐3−C‐13′ single bond with an oxido‐rearranged 6/5/6/6 fused ring system; artemordins G—K (7—11) were biogenetically connected by [4 + 2] cycloaddition reaction and artemordins G—J (7—10) possessed a novel 5/6/6/6/6/6/5‐heptacyclic fused ring system. Artemordins L—S (12—19) were formed by esterification, which involved three different types of sesquiterpenoids. Antihepatoma assay suggested that the most active compounds, artemordins B and H (2 and 8), exhibited inhibitory activities on three hepatoma cell lines with IC50 values of 26.9 and 25.1 μmol/L (HepG2), 29.5 and 18.3 μmol/L (Huh7), 19.7 and 15.7 μmol/L (SK‐Hep‐1). [ABSTRACT FROM AUTHOR]

In the field of molecular nonequilibrium transports, physical mechanisms of multiple reaction dynamics of these systems are the core of deep understanding complex reactions and transport mechanisms. In order to explore related mechanisms, establishing multiple systems coupled with tremendous exit dynamics and studying their exit dynamics properties are quite vital. Beyond previous researches, new stochastic transport processes are emphasized here. Multiple new exit dynamic systems are established, which are motivated by the multiplicity of paths and products of real biochemical processes in organisms. In order to ensure research universality, core system modeling factors are fully considered. Countable parallel orbits, uniform connection with external sources, countable parallel orbits as subsystems in middle lattices and influences of all lattices on transport trajectories on dynamic properties are analyzed. Dynamic properties of different particles located in orbits are explored by deeply studying average exit time and time scale. Quantitative spatiotemporal impacts are extensively studied. The rationality of average exit time as a time scale in the universal exit dynamic system is proved. Main findings and fruitful results can not only serve as theoretical bases for broadening reaction path modeling, but also be helpful to support understanding nonequilibrium transport mechanisms, especially stochastic biochemical processes. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Eight new guaiane‐type sesquiterpenoid trimers, artemsieverolactones A—H, possessing unprecedented scaffolds via biocatalyzed [4+2] Diels−Alder cycloaddition reactions were identified from Artemisia sieversiana. Their structures were determined by comprehensive spectroscopic data, single‐crystal X‐ray diffraction analyses, and ECD calculations. In terms of structure, artemsieverolactones A—H are first examples of sesquiterpenoid trimers from guaiane‐type sesquiterpenoid through four different [4+2] Diels−Alder cycloaddition models. Antihepatic fibrosis assay suggested that five compounds exhibited activity against HSC‐LX2 with IC50 values ranging from 37.8 to 117.1 μmol/L. The most active artemsieverolactone B (2) displayed significant inhibitory activity against HSC‐LX2 with IC50 value of 37.8 μmol/L, which was 3 times more active than the positive drug silybin (IC50, 139.7 μmol/L). Preliminary mechanism study revealed that artemsieverolactone B could inhibit the deposition of human collagen type I (Col I), human hyaluronic acid (HA), and human laminin (HL) with IC50 values of 40.4 μmol/L (Col I), 55.1 μmol/L (HL), 47.3 μmol/L (HA), which was 2 to 3‐fold more potent than silybin. [ABSTRACT FROM AUTHOR]

Gold (Au) with excellent properties, is widely used in many fields, resulting in the depletion of Au resources and environment pollution due to a great deal of wastewater containing Au(III) produced in the industrial production process. Hence, it is necessary to remove and recover Au from wastewater. In this work, a novel hyperbranched polyethyleneimine functionalized porous polyacrylonitrile/graphene oxide nanofiber membrane (HP-PAN/GO) for adsorption of Au(III) was fabricated by electrospinning, hot-water soak and grafting methods. The effect of the solution pH, initial concentration and contact time on the adsorption performance of HP-PAN/GO for Au(III) was explored by batch experiments. The adsorption process was investigated by pseudo-first-order kinetic, pseudo-second-order kinetic, intra particle diffusion models, Langmuir and Freundlich isotherms. The results showed that the HP-PAN/GO with abundant amino functional groups and pore structure was successfully fabricated. The adsorption and reduction of HP-PAN/GO for Au(III) were simultaneous, and Au(III) adsorbed HP-PAN/GO was partially reduced to elemental Au with hexagonal flakes and irregular particles, and the maximum adsorption capacity of HP-PAN/GO for Au(III) was 2601.27 mg·g−1. The removal rate of the HP-PAN/GO for Au(III) remained over 83% after five adsorption cycles. Moreover, the HP-PAN/GO had excellent adsorption selectivity in coexisting ion system. The HP-PAN/GO could be a promising candidate for effective removal and recovery of Au(III) in wastewater. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Artemiprincepsolides A—F (1—6) were isolated from Artemisia princeps guided by bioactivity and elucidated by comprehensive spectral data and ECD calculation. Compounds 1—3 represented the first connecting model of germacrane‐guaiane hetero‐dimeric adducts, and compounds 4—6 were eudesmane‐guaiane hetero‐coupled sesquiterpenoid dimers, meanwhile, all these were presumably formed by Diels‐Alder cycloaddition. Compounds 1—6 were evaluated for their hepatomatic cytotoxicity on three hepatoma cell lines, and demonstrated cytotoxicity with IC50 values in the range of 5.0—67.3 μmol/L. Interestingly, compound 1 manifested significant cytotoxicity against HepG2, Huh7, and SK‐Hep‐1 cells with IC50 values of 9.9, 9.2, and 5.0 μmol/L, which were almost equivalent to the positive control, sorafenib. Flow cytometry data and Western blot assays revealed the most active compound 1 dose‐dependently inhibited cell migration and invasion, and significantly induced HepG2 cells arrest in G2/M phase by downregulating proteins pcdc2 and upregulating the level of protein CyclinB1; and induced apoptosis by downregulating of Bcl‐2 expression and upregulating Bax level. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: 17 new guaiane‐type sesquiterpenoid dimers (GSDs), artemzhongdianolides B1—B17 (1—17), were isolated from Artemisia zhongdianensis under the guidance of bioassay, and elucidated by spectral analyses (HRESIMS, 1D and 2D NMR, IR, ECD). The absolute configuration of compounds 1, 3, 7, 9, 10, and 13 was determined by single‐crystal X‐ray diffraction analyses. Structurally, artemzhongdianolides B1 (1) and B2 (2) were the first example of the GSDs fused via a C‐13/C‐13' single bond, and artemzhongdianolides B3—B17 were [4 + 2] Diels–Alder adducts of two monomeric guaianolides. Most of the compounds showed antihepatoma cytotoxicity with IC50 values ranging from 9.9 to 170.1 μmol/L. Importantly, artemzhongdianolide B9 (9) was the most active one against three hepatoma cell lines with IC50 values of 13.1 μmol/L (HepG2), 19.5 μmol/L (Huh7), and 19.5 μmol/L (SK‐Hep‐1), and dose‐dependently inhibited cell migration and invasion, induced G1 cell cycle arrest and cell apoptosis in HepG2 cells. Compound 9 might suppress HepG2 cells via affecting the p38MAPK signaling pathway suggested by machine learning approach, and significantly upregulated expression of phosphorylated p38 validated by Western blot assay. [ABSTRACT FROM AUTHOR]

Artemongolins A–K (1–11), which are undescribed sesquiterpenoid dimers, were obtained from Artemisia mongolica and characterized through comprehensive spectral data, including HRESIMS, IR, 1D and 2D NMR, and ECD calculations. The absolute configurations of compounds 1, 4, and 7 were undoubtedly determined by a single-crystal X-ray crystallography. Artemongolins A–K (1–11) featured a rare 5/7/5/5/5/10 hexacyclic system composed of a germacrene and a guaianolide by a fused 2-oxaspiro[4,4]nonane-1-one ring system. Antihepatoma evaluation against three human hepatoma cell lines demonstrated that the most active compounds 5 and 6 displayed inhibitory activity with IC50 values of 88.6 and 57.0 (HepG2), 59.1 and 26.4 (Huh7), and 67.5 and 32.5 (SK-Hep-1) µM, respectively. [ABSTRACT FROM AUTHOR]

Inspired by our previous finding that disesquiterpenoids showed more potent antihepatoma cytotoxicity than their corresponding parent monomers, natural product‐like guaianolide‐germacranolide heterodimers were designed and synthesized from guaianolide diene and germacranolides via a biomimetic Diels–Alder reaction to provide three antihepatoma active dimers with novel scaffolds. To explore the structure–activity relationship, 31 derivatives containing ester, carbamate, ether, urea, amide, and triazole functional groups at C‐14′ were synthesized and evaluated for their cytotoxic activities against HepG2, Huh7, and SK‐Hep‐1 cell lines. Among them, 25 compounds were more potent than sorafenib against HepG2 cells, 15 compounds were stronger than sorafenib against Huh7 cells, and 17 compounds were stronger than sorafenib against SK‐Hep‐1 cells. Compound 23 showed the most potent cytotoxicity against three hepatoma cell lines with IC50 values of 4.4 µM (HepG2), 3.7 µM (Huh7), and 3.1 µM (SK‐Hep‐1), which were 2.7‐, 2.2‐, and 2.8‐fold more potent than sorafenib, respectively. The underlying mechanism study demonstrated that compound 23 could induce cell apoptosis, prevent cell migration and invasion, cause G2/M phase arrest in SK‐Hep‐1 cells. Network pharmacology analyses predicted PDGFRA was one of the potential targets of compound 23, and surface plasmon resonance (SPR) assay verified that 23 had strong affinity with PDGFRA with a dissociatin constant (KD) value of 90.2 nM. These promising findings revealed that structurally novel guaianolide‐germacranolide heterodimers might provide a new inspiration for the discovery of antihepatoma agents. [ABSTRACT FROM AUTHOR]

Ten new germacrane-type sesquiterpenoids, artemyrianosins A–J (1–10), were isolated from the aerial parts of Artemisia myriantha. Their structures were elucidated by spectral analyses including UV, IR, HRESIMS, 1D and 2D NMR, ECD and the absolute configurations of compounds 1 and 7–9 were characterized using X-ray crystallography. All isolates were tested their cytotoxicity against three human hepatoma cell lines (HepG2, Huh7, and SK-Hep-1), and compounds 1–3, 7, and 10 showed cytotoxicity with IC50 values ranging from 43.7 to 89.3 μM. Among them, the most active compound 3 exhibited activity against three human hepatoma cell lines with IC50 values of 43.7 μM (HepG2), 47.9 μM (Huh7), and 44.9 μM (SK-Hep-1). [ABSTRACT FROM AUTHOR]

The antidepressant activity of (+) and (−)-paeoveitol was first evaluated using the forced swimming test (FST), and (+)-paeoveitol showed potential antidepressant activity by decreasing immobility time of mice (by approximately 26.4%) in the FST at a dose of 20 mg/kg. To explore the structure-activity relationships (SARs) and obtain more potent compounds, twenty derivatives of (+)-paeoveitol were synthesized and evaluated for their agonistic activities on melatonin type I (MT1) and type II (MT2) receptors. As a results, compound 13 with an N-methylpiperazine fragment exhibited obvious effect on MT1 and MT2 receptors with EC50 values of 0.20 and 0.24 mM. Moreover, compound 13 dose-dependently decreased the immobility of mice in the FST and showed an inverted U-shaped dose-effect, and the most efficacious dose (at 40 mg/kg) was comparable to fluoxetine (20 mg/kg) with a reduced immobility time of 29.2% and 34.5%, respectively. In vivo neurochemical assays suggested that compound 13 obviously increased 5-hydroxytryptamine (5-HT), 5-hydroxyindoleacetic acid (5-HIAA) and norepinephrine (NE) levels in the mice brain, indicating that its antidepressant effects might be related to the monoaminergic system. In silico ADMET study revealed that 13 has favorable pharmacokinetic properties. These findings suggest that compound 13 could be a potential antidepressant agent. [ABSTRACT FROM AUTHOR]

By simulating nonequilibrium processes like biological transport, traffic transport, etc., totally asymmetric simple exclusion process (i.e., TASEP) is vital to understand stochastic dynamics of lattice systems. Stochastic networks using TASEP as underlying dynamics make a more practical generalization of traditional exclusion models, which better simulate real transport processes. According to real experimental data, a new network structure of nonaverage weight assignment at nodes is constructed to further understand physical mechanisms of molecular motors transporting along microtubules. Two typical kinesins, KIF3AC and KIF3CC, are used as modeling bases. High-tendency segments and low-tendency segments are introduced to characterize heterogeneous flow distribution at nodes. Multi-body system dynamics affected by the global density are studied. Edge densities are analyzed by using new mean-field theories compared with Monte Carlo simulations. New detailed structures of adsorption and desorption at nodes are considered. In order to restore a motor transport framework more suitable for real systems, analytical solutions and simulations of local statistical densities and phase diagrams affected by particle desorption and no desorption are obtained. This work provides help for understanding dynamical mechanisms of complex networks and other important nonlinear physics depicting molecular motors transport, cytoskeleton designs, structural optimizations, etc. [ABSTRACT FROM AUTHOR]

Our previous study demonstrated that guaiane-type sesquiterpenoid ludartin showed potent antihepatoma activity against two human hepatocellular carcinoma cell lines, HepG2 and Huh7, with IC50 values of 32.7 and 34.3 μM, respectively. In this study, 34 ludartin derivatives were designed, synthesized and evaluated for their cytotoxic activities against HepG2 and Huh7 cell lines using an MTT assay in vitro. As a result, 17 compounds increased the activity against HepG2 cells, and 20 compounds enhanced the activity against Huh7 cells; 14 derivatives 2, 4-7, 9, 11, 17, 24, 28-30 and 32-33 were superior to ludartin on both HepG2 and Huh7 cells. In particular, dimeric derivative 33 as the most active compound showed 20-fold and 17-fold enhancement of cytotoxicity against HepG2 and Huh7 cells compared to that of ludartin. These results suggested that compound 33 could serve as a promising lead compound against liver cancer. [ABSTRACT FROM AUTHOR]

In order to reflect new physical insights in understanding nonequilibrium phase transition mechanisms of real mesoscopic transport, a new exclusion process with horizontal and vertical binding energies is constructed. Fruitful developments of mean-field theories including developed simple, 2-lattice cluster, 4-lattice cluster and correlation mean-field theories are given. Typical order parameters are analytically solved and verified by simulation statistics. Evolution laws of phase boundaries with varied lane-changing rates, mobilities and binding energies are found via acquisitions of density profiles and phase diagrams. Fitting effects of developed analytical methods are quantitatively compared via Kullback–Leibler divergence. Findings show that developed simple mean-field theory (SMF) achieves better results in the fitting of each phase, while developed 2-lattice cluster mean-field theory (CMF) has better results in the fitting of low-density and coexistence phases. Developed 4-lattice CMF has better results in fitting low-density phase and high-density part of coexistence one, and developed correlation cluster mean-field theory (CCMF) has better results in the fitting except high-density phase. The minimum correlation element is introduced to explain differences among evaluations of analytical solutions under Kullback–Leibler divergence. The minimum correlation element size of SMF, CCMF, 2-lattice CMF and 4-lattice one is found to be 1, 1.5, 2 and 4, respectively. Intrinsic dynamics are found to have a great impact on analysis solutions, which indicate that analytical results brought by different minimum correlation elements need to be comprehensively considered to determine correlation degree, although evaluation results reveal that deviations between analytical solutions and simulation results increase with the minimum size of the related element. Effectiveness of developed theories is achieved in a more scientifically sound manner, which is helpful for evaluating rationality and effectiveness of analytical methods and critical phenomena of spatial correlations in nonequilibrium multi-body particle interaction systems. [ABSTRACT FROM AUTHOR]

The dammarane triterpenoid (20S,24R)-epoxy-dammarane-3β,12β,25-triol obtained from Cyclocarya paliurus in our previous study showed inhibitory activity on α-glucosidase in vitro with an inhibitory ratio of 32.2% at the concentration of 200 μM. In order to reveal the structure-activity relationships (SARs) and get more active compounds, 42 derivatives of (20S,24R)-epoxy-dammarane-3β,12β,25-triol were synthesized by chemical modification on the hydroxyls (C-3 and C-12), rings A and E, and assayed for their α-glucosidase and PTP1B inhibitory activities. Two compounds (8, 26) increased activity against α-glucosidase, and four compounds (8, 15, 26, 42) significantly inhibited PTP1B. It was noted that compounds 8 and 26 could inhibit both α-glucosidase and PTP1B as dual-target inhibitors with IC50 values of 489.8, 467.7 μM (α-glucosidase) and 319.7, 269.1 μM (PTP1B). Compound 26 was revealed to be a mix-type inhibitor on α-glucosidase and a noncompetitive-type inhibitor on PTP1B based on enzyme kinetic study. Furthermore, compound 42 could selectively inhibited PTP1B as a mix-type inhibitor with IC50 value of 134.9 μM, which was 2.5-fold higher than the positive control, suramin sodium (IC50 339.0 μM), but not inhibit α-glucosidase. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Inspired by the intriguing structures and remarkable activities of sesquiterpenoid dimers, 12 new sesquiterpenoid dimers, artematrovirenolides A—D (1—4) and artematrolides S—Z (8—12), were isolated from the EtOAc fraction of Artemisia atrovirens through a bioactivity‐guided approach. Their structures were elucidated by comprehensive spectroscopic data and absolute configuration was assigned based on single crystal X‐ray diffraction data and ECD calculations. Structurally, all compounds are presumably formed via [4+2] cycloaddition involving three connecting model. Compounds 1—4 are four novel hetero‐dimeric [4+2] Diels–Alder adducts dimerized from a rotundane‐type unit and a guaiane‐type monomer, and compounds 5—12 are eight new homo‐dimeric [4+2] adducts derived from two guaianolide moieties. A putative biosynthetic pathway for compounds 1—4 was also proposed. Compounds 4, 6, 7, and 10 demonstrated moderate cytotoxicity against HepG2, SMMC‐7721, and Huh7 cell lines with IC50 values ranging from 9.3 to 62.3 μmol/L. Interestingly, compounds 5 and 11 manifested cytotoxicity with IC50 values of 13.6 and 12.8 (HepG2), 18.5 and 13.1 (SMMC‐7721), and 16.5 and 19.4 μmol/L (Huh7), respectively, which were equivalent to the positive control, sorafenib. This investigation suggests that compounds 5 and 11 might be considered as potent antihepatoma candidates and deserve further structural modification and mechanism study. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: The EtOAc fraction of Alpinia katsumadai seeds showed significant inhibition on glycogen phosphorylase a (GPa) with inhibitory ratios of 97.9% and 64.6% at concentrations of 200 and 100 μg/mL, respectively. Bioactivity‐guided isolation afforded 15 new diarylheptanoid‐flavanone hybrids, katsumadainols B1—B15 (1—15), together with eight known ones (16—23). Compounds 4—10 and 12—21 exhibited activity against GPa with IC50 values of 10.1—95.4 μmol/L; compounds 4, 5, 16, and 17 displayed inhibitory effects on α‐glucosidase with IC50 values of 7.1, 12.4, 7.2, and 8.3 μmol/L, obviously higher than acarbose (IC50, 209.1 μmol/L); compounds 4—6, 14, 16—20, 22, and 23 were PTP1B/TCPTP selective inhibitors with IC50 values of 40.7—95.8 μmol/L; compounds 4, 5, 16, and 17 showed DPP4 inhibitory effects with inhibitory ratios of 50.0%—54.2% (200 μmol/L). Diarylheptanoid‐flavanone hybrids (4, 5, 16, and 17) with a p‐hydroxybenzyl at C‐6 position represent a promising class of multiple‐target antidiabetic agents inhibiting GPa, α‐glucosidase, PTP1B, and DPP4. [ABSTRACT FROM AUTHOR]

Four new sesquiterpenoids, artemyrianins A–D (1–4), and three new norlignans, artemyrianins E–G (5–7), together with five known compounds (8–12), were isolated from the aerial parts of Artemisia myriantha (Asteraceae). The new compounds were established by spectroscopic data analyses (HRMS, IR, 1D and 2D NMR), and their absolute configurations were confirmed by the single-crystal X-ray diffraction or ECD calculations. The isolates showed cytotoxicity against HepG2 cells with IC50 values ranging from 33.3 to 145.2 μM. [ABSTRACT FROM AUTHOR]

Two new sesquiterpenoids, artemlavanins A (1) and B (3), together with fifteen known compounds (2 and 4−17) were isolated from the EtOH extract of Artemisia lavandulaefolia. The structures of new compounds were elucidated by extensive spectroscopic analyses (HRESIMS, 1D and 2D NMR) and ECD calculations. Compound 1 was a sesquiterpenoid lactone possessing a rearranged eudesmane skeleton; compounds 2–5, 6–8, 9 and 10–12 belonged to the eudesmane, guaiane, oppositane and farnesane sesquiterpenoids, respectively; compounds 13–17 were the phenyl derivatives with a 4-hydroxyacetophenone moiety. Twelve compounds (1–3, 5–7, 10–12, 14, 15 and 17) displayed cytotoxicity against hepatic stellate cell line LX2 (HSC-LX2) with IC50 values ranging from 35.1 to 370.3 μM. Compounds 2, 7, 10–12 and 17 exhibited the stronger cytotoxicity than silybin (IC50, 169.6 μM) with IC50 values of 82.1, 35.1, 95.0, 83.8, 81.6 and 90.1 μM. Compound 7 as the most active one showed significant inhibition on the deposition of human collagen type I (Col I), human hyaluronic acid (HA) and human laminin (HL) with IC50 values of 10.7, 24.5 and 13.3 μM. [ABSTRACT FROM AUTHOR]

Over the past few years, artificial enzymes have attracted enormous attention due to their high stabilities and cost-effective productions. In this work, metal–organic framework-derived SiW12@Co3O4 was synthesized in large quantities by stirring the mixture at ambient temperature and calcination. The obtained SiW12@Co3O4 exhibited a highly inherent peroxidase-like activity and excellent stability. Kinetic studies demonstrated that the synthesized SiW12@Co3O4 had a strong binding affinity to 3,3′,5,5′-tetramethylbenzidine (TMB), stronger than HRP had. Specifically, the peroxidase-like activity of SiW12@Co3O4 in an aqueous solution was well maintained after incubation at an elevated temperature, at an extreme pH and for a long time. A SiW12@Co3O4-based method was further developed for H2O2 and one-pot glucose detection with good sensitivity and reliability. The facile synthesis approach is expected to facilitate the practical use of metal–organic frameworks and their derivatives as enzyme mimics in the future. [ABSTRACT FROM AUTHOR]

Twenty-four gramine derivatives were synthesized and evaluated on MT1and 5-HT1Areceptorsin vitro. Among them, seven derivatives (7,8,16,19,20,21,and24)exhibited higher agonisting activities on MT1or 5-HT1Areceptors. Compared with gramine, derivatives7,8,16,19,20,21,and24displayed 1.6–3.5-fold increase in agonistic rates on 5-HT1Areceptor. Particularly, derivatives7,19,and21exhibited significant agonistic activities on MT1and 5-HT1Areceptors with EC50values of 0.51, 0.39, 0.50 mΜ and 0.28, 0.46, 0.23 mΜ, respectively. The preliminary structure–activity relationships of gramine derivatives were summarized for further investigation on MT1and 5-HT1Areceptors as new potential agonists. [ABSTRACT FROM PUBLISHER]

Sixteen tropinone derivatives were prepared, and their antitumor activities against five human cancer cells (HL-60, A-549, SMMC-7721, MCF-7 and SW480) were evaluated with MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxy methoxyphenyl)-2-(4-sulfopheny)-2H-tetrazolium] assay. Most of the derivatives exhibited better activities compared with tropinone at the concentration of 40 μM. Particularly, derivative 6 showed significant activities with IC values of 3.39, 13.59, 6.65, 13.09 and 12.38 μM respectively against HL-60, A-549, SMMC-7721, MCF-7 and SW480 cells, which suggested more potent activities than that of cis-dichlorodiamineplatinum (DDP). Graphical Abstract: [ABSTRACT FROM AUTHOR]

Let be a prime. The Sylow -number of a finite group , which is the number of Sylow -subgroups of , is called solvable if its -part is congruent to modulo for any prime . P. Hall showed that solvable groups only have solvable Sylow numbers, and M. Hall showed that the Sylow -number of a finite group is the product of two kinds of factors: of prime powers with (mod ) and of the number of Sylow -subgroups in certain finite simple groups (involved in ). These classical results lead to the investigation of solvable Sylow numbers of finite simple groups. In this paper, we show that a finite nonabelian simple group has only solvable Sylow numbers if and only if it is isomorphic to for a Mersenne prime. [ABSTRACT FROM AUTHOR]

The first direct and enantioselective vinylogous Michael/cyclization cascade reaction between acyclic β,γ-unsaturated amides and isatylidene malononitriles has been developed. Optically active spirocyclic oxindoles have been obtained in goodto- excellent yields (84-96%) and enantioselectivity (79-97% ee) in the presence of 2 mol% (DHQD)2PYR [2,5-diphenyl-4,6-bis(9-O-dihydroquinyl) pyrimidine]. [ABSTRACT FROM AUTHOR]

An enantioselective domino reaction of 4-bromo-3-oxobutanoates with isatin-derived ketimines was developed to construct 3-amino-2-oxindoles with a quaternary stereocentre. In the presence of 1 mol-% of a bifunctional squaramide organocatalyst, the desired products were achieved in high yields (90-97 %) and with excellent enantioselectivities (92-99 % ee). [ABSTRACT FROM AUTHOR]

Chiral organophosphine-catalyzed enantioselective Rauhut–Currier reaction has been disclosed for the first time. With l-valine-derived phosphinothiourea, the intramolecular Rauhut–Currier reaction of bis(enones) was achieved in good yields (up to 99%) with excellent enantioselectivities (up to 99.4% ee). [ABSTRACT FROM AUTHOR]

A correction to the article "Enantioselective Squaramide-Catalysed Domino Mannich-Cyclization Reaction of Isatin Imines" that was published in February 24, 2014 issue is presented.