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Chiral-substituted 3-amino tetrahydro-2H-pyran-2-ones were prepared in excellent enantioselectivities (up to 99% ee) via an organo-catalyzed cascade procedure with N-TFA-Gly-Bt and α,β-unsaturated aldehydes as the substrates. The corresponding tetrahydro-2H-pyran-2-ones can be used for further synthetic transformations that furnish chiral-substituted 3-aminopiperidin-2-ones with high levels of stereoselectivity.

Chordoid glioma (CG), a rare slow-growing brain tumor, mainly occurs in the region of the third ventricle. Although its degree of malignancy is relatively low, its clinical prognosis is poor due to obscure clinical manifestations and the particular growing position. Currently, gross total resection is the best available method for treatment of CG. However, the tumor is located in the deep structure of the brain and close to neurovascular structure so it is difficult to remove completely. We report a case of right frontal parietal fibrous meningioma with CG of the third ventricle detected during postoperative 5-year follow-up. Different from previous reports, in the present case, CG merged with another solid brain tumor, and combined with peri and postoperative sodium ion metabolism disorder. The occurrence of two primary intracranial tumors without a history of radiation therapy or genetic disease is a very rare event. Whole-exome sequencing showed that the meningioma shared 25 gene mutations with CG. In addition, the PRKCAD436H CG marker gene mutation also existed in this patient. In this article, we reviewed the latest literature on this rare brain tumor, summarized its clinical manifestations, imaging and pathological characteristics, and discussed the mechanism related to its occurrence and the reasons for sodium ion disorder.

Tyrosinase (TYR) was covalently immobilized onto amino-functionalized carbon felt (CF) surface via glutaraldehyde (GA). Prior to the TYR-immobilization, primary amino group was introduced to the CF surface by treatment with 3-aminopropyltriethoxysilane (APTES). The resulting TYR-immobilized CF was used as a working electrode unit of an electrochemical flow-through detector for mono- and di-phenolic compounds (i.e., catechol, p-cresol, phenol and p-chlorophenol). Additionally, flow injection peaks based on electroreduction of the enzymatically produced o-quinone species were detected at −0.05 V vs. Ag/AgCl. The resulting TYR/GA/APTES/CF biosensor responded well to all compounds tested with limits of detection range from 7.5 to 35 nmol−1 (based on three times S/N ratio). Moreover, such modified electrode exhibits good stability and reproducibility for catechol. No serious degradation of the peak current was found over 30 consecutive injections.

The Sonogashira cross-coupling reaction is one of the most important and widely used sp2–sp carbon–carbon bond formation reactions in organic synthesis. Up to now, the exact mechanism of the palladium/copper-catalyzed Sonogashira reaction is far from being fully understood, mainly due to the difficulties in clarifying the combination behavior of the two metal catalysts. In this study, DFT calculations have been performed to elucidate the mechanism of the copper-cocatalyzed Sonogashira cross-coupling reaction, where bis(triphenylphosphino)palladium was used as a catalyst and Cs2CO3 was applied as a base. In an agreement between theory and experiment, the Cu cycle could favorably generate an I–-coordinated copper acetylide as the catalytically active species rather than the generally considered neutral copper acetylide. In addition, the transmetalation is calculated to be the rate-determining step. The results reported herein are expected to have broad mechanistic implications for other bimetal-catalyzed re...

A meat probe can be used to help end users to get customized and precise roasting of meat, fish and poultry by monitoring the core temperature. Conventional meat probe applied in an oven uses a wire to connect the probe with the oven. Recently, the market requires a meat probe with the same size as conventional one but be wireless and battery-less for more utility freedom, better water and oil proof, easy clean and maintenance-free. This paper describes the design procedure as well as the experimental performance of a wideband helix antenna which covers both 868MHz and 915MHz bands for a wireless meat probe to harvest RF energy with high efficiency. The helix antenna has a circular patch in the bottom to enhance its bandwidth and reuses the metal cylinder of the meat probe as RF choke to reduce the adverse impact caused by the variation of food parameters during cooking. Simulation results show that the helix antenna has return losses better than 8dB and antenna efficiency higher than 70% when the meat probe is inserted to a piece of meat during cooking. The experiment results show that wireless meat probe using the antenna has better stability in measuring food temperature than conventional helix antenna.

An asymmetric fluorination process of 4-substituted pyrazolones catalyzed by quinine is revealed. The reaction afforded a wide range of 4-fluorinated pyrazol-5-ones with excellent yields (up to 98%) and moderate to good enantioselectivities (up to 81% ee).

Pyrazinamide (PZA) causes serious hepatotoxicity, but little is known about the exact mechanism by which PZA induced liver injury. The peroxisome proliferator-activated receptors alpha (PPARα) is highly expressed in the liver and modulates the intracellular lipidmetabolism. So far, the role of PPARα in the hepatotoxicity of PZA is unknown. In the present study, we described the hepatotoxic effects of PZA and the role of PPARα and its target genes in the downstream pathway including L-Fabp, Lpl, Cpt-1b, Acaa1, Apo-A1 and Me1 in this process. We found PZA induced the liver lipid metabolism disorder and PPARα expressionwas down-regulated which had a significant inverse correlation with liver injury degree. These changeswere ameliorated by fenofibrate, the co-treatment that acts as a PPARα agonist. In contrast, short-termstarvation significantly aggravated the severity of PZA-induced liver injury. In conclusion, this study demonstrated the critical role played by PPARα in PZA-induced hepatotoxicity and provided a better understanding of the molecular mechanisms underlying PZA-induced liver injury. Copyright © 2016 John Wiley & Sons, Ltd.

α-Aminomethyl alkyl ketones reacted smoothly with α,β-unsaturated aldehydes via a tandem process catalysed by diphenylprolinol silyl ether/4-bromobenzoic acid. 2-Alkanoyl-3-aryl-5-hydroxy pyrrolidines were prepared in high yields (up to 99%) and enatioselectivities (>99% ee). The absolute configurations of the products were unambiguously confirmed by single-crystal diffraction.

Triptolide (TP) has been used as one of the most common systemic treatments for various diseases since the 1960s. However, TP displays diverse side effects on various organs, which limits its clinical application. To overcome this issue, numerous C-14-hydroxyl group derivatives of TP have been synthesized. In this research, the C-14-hydroxyl group of TP is modified by a cell-penetrating peptide polyarginine (R7). The derivative TP-disulfide-CR7 (TP-S-S-CR7) containing a disulfide linkage between TP and R7 possesses less toxicity at various concentrations on the immortal human keratinocyte (HaCaT) cell line by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay compared with free TP. Treating HaCaT cells with TP (100 nM) could increase intracellular ROS (reactive oxygen species) and decrease the activity of SOD (superoxide dismutase). Meanwhile, treating HaCaT cells with equimolar concentration of TP-S-S-CR7 did not cause both of the above TP-induced alterations. In addition, TP-S-S-CR...

A versatile method for the synthesis of mono- and bis-arylthioindoles via I 2 catalysed direct oxidative sulfenylation of indoles with thiophenols (especially mercaptobenzoic acids) has been presented. This system features environmental friendliness, easy operation, and mild reaction conditions, and shows a broad functional group tolerance furnishing good to excellent yields.

A highly efficient and practical one-pot sequential process, consisting of an organocatalytic enantioselective Friedel-Crafts-type addition of 4-nonsubstituted pyrazolones to isatin-derived N-Boc ketimines and a subsequent diastereoselective fluorination of the pyrazolone moiety, is developed. This reaction sequence delivers novel oxindole-pyrazolone adducts featuring vicinal tetrasubstituted stereocenters with a 0.5 mol % catalyst loading in high yield with excellent enantio- and diastereocontrol. Notably, chloro, bromo, and thioether functionalities can be readily incorporated, rendering a broad diversity of the product.

Two new and simple chemosensors, 1-(anthracen-9-ylmethyl)urea (3a) and 1-(anthracen-9-ylmethyl)thiourea (3b) bearing anthracene moiety, were synthesized from anthracen-9-ylmethanamine. Their UV–Vis absorption, fluorescence emission and potential application for the detection of ions were investigated. Of note is that their fluorescence emission excited with 370 nm could be quenched upon addition of Fe3+, whereby the highly selective recognition for Fe3+ was noticed. Furthermore, ensembles based on 3a-Fe3+ and 3b-Fe3+ complexes having the specific binding affinity for F− show rapid and selective detection of F− over other anions with a fluorescence turn-on mode.

Trifluoromethyl ketones (TFMKs) significantly contribute to biologically active compounds and special materials. TFMKs can be prepared by “trifluoroacetic ester/ketone metathesis” along with the accompanying products, aromatic acid esters. As an important extension of our previous studies on the use of aryl alkyl ketones, wherein the separation of the resulting TFMKs and aromatic acid esters proved problematic, i-Pr and t-Bu alkyl ketones were shown in this work to be competent reaction partners for easy TFMK separation from the product mixtures, thereby providing a practical synthesis route to TFMKs. With the removal of accompanying products, i-Pr and t-Bu carboxylic esters, TFMKs with high boiling points were efficiently obtained by distillation or recrystallization. Furthermore, a solvent-free condition was also effective for this reaction, which allowed TFMKs with low boiling points to be separated from the reaction mixture by distillation in good yield.

In this paper, a low-cost solution to miniaturize systems at the board-level is demonstrated using a novel embedding scheme. The miniaturization concept is demonstrated using a state-of-the-art contact-less power module for low-power house-hold appliances. A highly-miniaturized contact-less power receiver module has been designed, fabricated, assembled and tested using low-cost fabrication and assembly processes. Electrical and thermal tests have been performed to ensure that the proposed approach does not degrade the electrical or thermal performance of the module. Thickness reduction of the order of 40% has been achieved with a given set of components and substrate thicknesses with minimal increase in the planar area.

Deoxypodophyllotoxin (DPT), a naturally occurring microtubule destabilizer, inhibits tubulin polymerization and causes cell cycle arrest at G2/M phase in tumor cells. However, the anti-tumor effect and specific mechanism of DPT in non-small cell lung cancer (NSCLC) are still poorly understood. In this study, we determined the anti-tumor effect and potential mechanism of DPT in the NSCLC cell line, NCI-H460 (H460). First, we demonstrated that DPT significantly inhibits the proliferation of H460 cells in vitro and the growth of H460 xenografts in vivo. In further studies, DPT triggered necroptosis in H460 cells with the following characteristics: (I) necrotic cell death morphology; (II) autophagy; (III) loss of plasma membrane integrity; (IV) loss of mitochondria membrane potential; (V) elevation of reactive oxygen species levels; and (VI) specific inhibition of necroptosis via a small molecule, necrostatin-1. This study also revealed that DPT has a similar effect towards the drug-sensitive cancer cell line, H460, and the drug-resistant cell line, H460/Bcl-xL. To our knowledge, this is the first report to document the induction of necroptosis by a microtubule-targeting agent to circumvent cancer drug resistance, thereby providing a new potential choice for clinical cancer therapy, especially drug-resistant cancer therapy.

A novel library of chiral guanidines featuring a tartaric acid skeleton was developed from diethyl l-tartrate. These guanidines are easily accessed with tunable steric and electronic properties. The utilities of the guanidines were highlighted by their ability to catalyze the α-hydroxylation of β-ketoesters and β-diketones with remarkable efficiency and excellent enantioselectivity.

Organizational culture is context-specific and it can impact organizational effectiveness in certain mechanism. From Competing Values Framework (CVF) prospective, this study examines the correlations among organizational culture, organizational citizenship behavior (OCB), and organizational effectiveness. Furthermore, this study analyzes the possible mediating role of OCB in the relationship between organizational culture and organizational effectiveness. A questionnaire-based survey was used to measure the related constructs. The results suggest that OCB partially mediates the impact of organizational culture on organizational effectiveness. The results also indicate the feasibility of impact mechanism of organizational culture on effectiveness. The research findings provide the implications for project management literature and practices.

leading to 4-fluorinated pyrazolones (II) and (IV) with moderate to good enantioselectivities

A highly efficient and practical one-pot sequential process, consisting of an organocatalytic enantioselective Friedel–Crafts-type addition of 4-nonsubstituted pyrazolones to isatin-derived N-Boc ketimines and a subsequent diastereoselective fluorination of the pyrazolone moiety, is developed. This reaction sequence delivers novel oxindole–pyrazolone adducts featuring vicinal tetrasubstituted stereocenters with a 0.5 mol % catalyst loading in high yield with excellent enantio- and diastereocontrol. Notably, chloro, bromo, and thioether functionalities can be readily incorporated, rendering a broad diversity of the product.

Pyrazinamide (PZA) causes serious hepatotoxicity, but little is known about the exact mechanism by which PZA induced liver injury. The peroxisome proliferator-activated receptors alpha (PPARα) is highly expressed in the liver and modulates the intracellular lipidmetabolism. So far, the role of PPARα in the hepatotoxicity of PZA is unknown. In the present study, we described the hepatotoxic effects of PZA and the role of PPARα and its target genes in the downstream pathway including L-Fabp, Lpl, Cpt-1b, Acaa1, Apo-A1 and Me1 in this process. We found PZA induced the liver lipid metabolism disorder and PPARα expressionwas down-regulated which had a significant inverse correlation with liver injury degree. These changeswere ameliorated by fenofibrate, the co-treatment that acts as a PPARα agonist. In contrast, short-termstarvation significantly aggravated the severity of PZA-induced liver injury. In conclusion, this study demonstrated the critical role played by PPARα in PZA-induced hepatotoxicity and provided a better understanding of the molecular mechanisms underlying PZA-induced liver injury. Copyright © 2016 John WileySons, Ltd.

With the direct use of allylic alcohols as allylating agents, the Friedel-Crafts-type allylic alkylation of nitrogen-containing aromatic compounds catalyzed by a [Mo(3)S(4)Pd(η(3)-allyl)] cluster is achieved. With a 3 mol % catalyst loading in acetonitrile at reflux or 60 °C, a variety of N,N-dialkylanilines and indoles reacted smoothly with allylic alcohols to afford the Friedel-Crafts-type allylation products in good to excellent yields with high levels of regioselectivity.

1-Hexene polymerization catalyzed by dicationic rare earth metal alkyl species [Ln(iPr-trisox)(CH2SiMe3)]2+ (Ln = Sc and Y; trisox = trisoxazoline) has been computationally studied by using QM/MM approach. It has been found that the initiation of 1-hexene polymerization kinetically prefers 1,2-insertion (free energy barrier of 17.23 kcal/mol) to 2,1-insertion (free energy barrier of 20.05 kcal/mol). Such a preference of 1,2-insertion has been also found for chain propagation stage. The isotactic polymerization was computed to be more kinetically preferable in comparison with syndiotactic manner, and the dicationic system resulted in lower insertion free energy barrier and more stable insertion product in comparison with the monocationic system. The stereoselectivity was found to follow chain-end mechanism, and the isospecific insertion of 1-hexene is mainly controlled by kinetics. In addition, the current computational results, for the first time, indicate that the higher activity of Sc species toward 1-h...

Second-, third-, and fourth-generation hyperbranched aliphatic polyols namely Boltorn® H20, Boltorn H30, and Boltorn H40 were endcapped with azido and activated acetylenic groups in good to excellent yields (75–95%) following an acid catalyzed procedure. The resultant terminally functionalized dendritic azido and acetylenic groups undergo 1,3-dipolar cycloaddition using methyl (or ethyl) propiolate and benzyl azide, respectively, under catalytic or noncatalytic conditions below 40 °C to yield 1,2,3-triazole dendrimeric polymers in 82–95% yield, under extremely mild conditions that could be applied for compounds sensitive to acid, base, or heat. The dendritic azido and activated acetylenic derivatives may act as novel scaffolds to tune the mechanical properties of different polymers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3748–3756, 2009

Poly(vinylidene fluoride) (PVDF)/clay nanocomposites with different clay contents were prepared by melt intercalation. The effects of clay on crystalline structure of PVDF were characterized, compared and discussed. For the nanocomposite containing 0.4 wt.% clay, the α phase coexists with the γ phase in the PVDF matrix in room temperature, however, the γ phase is unstable at 160 °C. When clay contents in the nanocomposites are greater 1 wt.%, the α phase coexists with the β phase. The β phase remains unchanged even after annealing. With increasing clay content, the location of the (021) reflection of α phase shifts to lower angle, while that of the (002) refection shifts to higher angle. Clay loading also induces the imperfection of α crystals. The results are attributed to the nucleation of PVDF on nanometer-size clay layers and the confining effect of nanometer-size clay on PVDF.