Brønsted acid-mediated tandem cyclization of triarylphosphines and generated -alkynyl quinone methides: access to heterocyclic quaternary phosphonium salts.

Heterocyclic Quaternary Phosphonium Salts (HQPS) have emerged as promising chemicals for organic synthesis and medicinal chemistry. However, the present synthetic methodology of this type of compound is still limited. Here, we report a deconstructive reorganization strategy based on Brønsted acid-mediated tandem 1,4 addition/intramolecular cyclization of triphenylphosphine derivatives and generated -AQMs for the first time.

Alkaloid from diels root against gastrointestinal cancer: Acetoxytabernosine inhibits apoptosis in hepatocellular carcinoma cells.

Liver cancer belongs to Gastrointestinal (GI) malignancies which is a common clinical disease, a thorny public health problem, and one of the major diseases that endanger human health. Molecules from natural products (NPs) or their derivatives play an increasingly important role in various chronic diseases such as GI cancers. The chemical composition of the roots was studied using silica column chromatography, gel chromatography, recrystallization, and HPLC, and the compounds were structurally identified by modern spectral analysis using mass spectrometry (MS) and nuclear magnetic resonance (H-, C-, HMQC-, HMBC-, and H-HCOSY-NMR), ultraviolet and visible spectrum (UV), and electronic Circular Dichroism (ECD).

Active fault tolerant tracking control of turbofan engine based on virtual actuator.

In this paper, an active fault-tolerant tracking control scheme for the turbofan engine under dynamic and simultaneous actuator faults and sensor faults under disturbances is proposed. First, based on the linear parameter-varying model of the turbofan engine, an H state feedback nominal controller is designed so as to achieve rotor speed tracking control with adaptive gain scheduling characteristics at different working conditions for the turbofan engine. Next, for the control system with simultaneous multiplicative actuator faults and additive sensor faults, a virtual actuator based active fault-tolerant tracking control strategy is developed to reconfigure the system such that it can obtain the similar behavior to the fault-free system without modifying the nominal controller.

Abscisic acid modulates differential physiological and biochemical responses of roots, stems, and leaves in mung bean seedlings to cadmium stress.

Experiments were conducted to determine how exogenous abscisic acid (ABA) mediates the tolerance of plants to cadmium (Cd) exposure. Cd stress strongly reduced all the growth parameters of mung bean seedlings. Cd significantly increased ascorbate peroxidase (APX) and catalase (CAT) activities in roots and stems, and peroxidase (POD) activities in roots, stems, and leaves of mung bean seedlings.

[Indicators of Groundwater Evolution Processes Based on Hydrochemistry and Environmental Isotopes: A Case Study of the Dongyuan Drinking Water Source Area in Ji'nan City].

The Dongyuan groundwater source area, which is the main drinking water source of Ji'nan City, is karst fissure water. To identify groundwater recharge sources, the influence of surface water, hydrochemical evolution, hydrochemical and isotopic components (H and O) of groundwater and surface water samples collected from the Dongyuan groundwater source were investigated.The results showed that the hydrochemical characteristics of groundwater were similar, and the main ions were Ca, HCO, and SO.

Lewis Base-Catalyzed [4 + 3] Annulation of ortho-Quinone Methides and MBH Carbonates: Synthesis of Functionalized Benzo[ b]oxepines Bearing Oxindole Scaffolds.

A novel Lewis base-catalyzed [4 + 3] annulation process for the construction of benzo[ b]oxepine scaffolds has been developed. 1,4-Diazabicyclo[2.2.

[Behavioral responses of Holotrichia oblita larvae to root exudates from three host plants].

The larva of Holotrichia oblita is a serious soil pest that feed with plant roots in north China. To explore the effects of host root exudates on the larva could provide theoretical basis for the development of green prevention and control methods. In order to elucidate the behavioral responses of Holotrichia oblita larva to the roots of peanut, soybean and maize, an experiment was conducted using the Y-olfactometers with the air as control.

Acupoint Embedding of Polyglactin 910 Sutures in Patients with Chronic Pain due to Cervical Spondylotic Radiculopathy: A Multicenter, Randomized, Controlled Clinical Trial.

Objective: We aimed to investigate the effectiveness of acupoint polyglactin 910 (PGLA) embedding in patients with cervical spondylotic radiculopathy (CSR).

Methods: A total of 102 CSR patients with neck and shoulder pain were recruited and assigned randomly into three groups: the sham acupoint embedding (SAE) group, the middle-layer acupoint PGLA embedding (MAPE) group, and the deep-layer acupoint PGLA embedding (DAPE) group. The primary outcomes were Visual Analog Scale (VAS) scores showing the analgesic effects of treatment.

Legacy and emerging contaminants in coastal surface sediments around Hainan Island in South China.

Emerging and legacy hydrophobic pollutants, including halogenated flame retardants (HFRs), organophosphorus FRs (OPFRs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs), as well as polycyclic aromatic hydrocarbons (PAHs) were determined in coastal sediments of Hainan Island, southern China, where little information is known about their contamination. The HFRs were dominated by decabrominated diphenyl ethers (median = 1.32 ng/g) and novel decabromodiphenyl ethane (1.

Lewis Acid Catalyzed Tandem 1,4-Conjugate Addition/Cyclization of in Situ Generated Alkynyl o-Quinone Methides and Electron-Rich Phenols: Synthesis of Dioxabicyclo[3.3.1]nonane Skeletons.

A versatile Lewis acid catalyzed tandem cyclization of in situ generated alkynyl o-quinone methides ( o-AQMs) with electron-rich phenols has been developed on the basis of the mode involving an intermolecular 1,4-conjugate addition/6-endo cyclization/1,3-aryl shift/intramolecular 1,4-conjugate addition cascade. This reaction provides a new method for expeditious assembly of synthetically and biologically interesting tetracyclic bridged dioxabicyclo[3.3.

Metal-Free One-Pot Synthesis of 3-Phosphinoylbenzofurans via Phospha-Michael Addition/Cyclization of H-Phosphine Oxides and in Situ Generated ortho-Quinone Methides.

A novel metal-free one-pot protocol for the effective and efficient synthesis of 3-phosphinoylbenzofurans via a phospha-Michael addition/cyclization of H-phosphine oxides and in situ generated ortho-quinone methides is described. Based on the expeditious construction of C(sp)-P bonds, asymmetric synthesis of optically pure 3-phosphinoylbenzofurans containing chiral P-stereogenic center has also been probed by using chiral R-(-)-menthyl phenylphosphine oxide.

[Identification of Sulfate Sources in the Groundwater System of Zaozhuang: Evidences from Isotopic and Hydrochemical Characteristics].

Karst groundwater is an important source of water supply for the industrial and agricultural proposes and drinking water in Zaozhuang City. In recent years, with the development of industrialization and increasing of domestic water consumption, the sulfate pollution of karst groundwater has become a serious problem. 36 samples of surface and different depth of groundwater were collected in southern Zaozhuang City in August, 2014.

Diallyl disulfide suppresses epithelial-mesenchymal transition, invasion and proliferation by downregulation of LIMK1 in gastric cancer.

Diallyl disulfide (DADS) has been shown to have multi-targeted antitumor activities. We have previously discovered that it has a repressive effect on LIM kinase-1 (LIMK1) expression in gastric cancer MGC803 cells. This suggests that DADS may inhibit epithelial-mesenchymal transition (EMT) by downregulating LIMK1, resulting in the inhibition of invasion and growth in gastric cancer.

[Analysis of optic crosstalk correction for pushbroom hyperspectral data].

Based on the imaging process of pushbroom hyperspectral imager, a correction method for optic crosstalk was developed. An area that has white calibration target was selected as reference data. The target pixels crosstalk quantity was gained using the subtraction between the two lines of reference data, and it was fitted to restrain noise.

Relationship between SERPING1 rs2511989 polymorphism and age-related macular degeneration risk: a meta-analysis.

Purpose: We conducted a meta-analysis aiming to evaluate the relationship between a common polymorphism (rs2511989 G>A) in the SERPING1 gene and the risk of age-related macular degeneration (AMD).

Methods: The PubMed, CISCOM, CINAHL, Web of Science, Google Scholar, EBSCO, Cochrane Library, and CBM databases were searched for relevant articles published before November 1, 2013, without any language restrictions. A meta-analysis was conducted using STATA 12.

Chiral separation of β-blockers by MEEKC using neutral microemulsion: Analysis of separation mechanism and further elucidation of resolution equation.

Based on the investigation of the effect of microemulsion charge on the chiral separation, a new chiral separation method with MEEKC employing neutral microemulsion was established. The method used a microemulsion containing 3.0% (w/v) neutral surfactant Tween 20 and 0.

Protection of ultra-filtration extract from Danggui Buxue Decoction on oxidative damage in cardiomyocytes of neonatal rats and its mechanism.

Objective: To investigate whether the administration of the ultra-filtration extract from Danggui Buxue Decoction (EDBD) was able to protect cardiomyocytes from oxidative injury of rats induced by hydrogen peroxide (H(2)O(2)) and its potential mechanism.

Methods: Myocardial cells from 1- to 2-day-old neonatal rats were cultured in Dulbecco's modified Eagle's medium low-glucose and Ham's F12 medium (1:1), and the cellular injury was induced by H(2)O(2). The ultra-filtration extract mixture from Angelica sinensis and Hedysarum polybotrys was given in three doses of 3.

Micelle to solvent stacking of two alkaloids in nonaqueous capillary electrophoresis.

This paper for the first time describes the development of micelle to solvent stacking (MSS) to nonaqueous capillary electrophoresis (NACE). In this proposed MSS-NACE, sodium dodecyl sulfate (SDS) micelles transport, release, and focus analytes from the sample solution to the running buffer using methanol as their solvent. After the focusing step, the focused analytes were separated via NACE.

A novel cross-H-channel interface for flow injection-capillary electrophoresis to reduce sample requirement and improve sensitivity.

In this study, a cross-H-channel interface was constructed for coupling flow injection with capillary electrophoresis (FI-CE) to reduce sample requirement and sensitivity loss in the typical FI-CE. Based on this cross-H-channel interface, a new FI-CE system was established, in which sample introduction was performed by directly injecting sample solution along a thin capillary (50 μm, i.d.

Diallyl disulfide induces apoptosis in human leukemia HL-60 cells through activation of JNK mediated by reactive oxygen.

Diallyl disulfide (DADS) is a chemopreventive agent that can induce apoptosis in many tumor cells. Reactive oxygen species (ROS) are important mediators in apoptosis induced by various stimuli, including chemopreventive agents. The phosphotransferase c-JUN N-terminal kinase (JNK) has been shown to regulate apoptosis.

Role of Ras-related C3 botulinum toxin substrate 2 (Rac2), NADPH oxidase and reactive oxygen species in diallyl disulphide-induced apoptosis of human leukaemia HL-60 cells.

1. Diallyl disulphide (DADS) has potential as a chemopreventive and therapeutic agent. Previous studies have reported that Ras-related C3 botulinum toxin substrate 2 (Rac2), a regulatory subunit of the NADPH oxidase complex, is upregulated in DADS-induced apoptosis in human leukaemia HL-60 cells.

Adsorption dynamics of binary mixture of Gemini surfactant and opposite-charged conventional surfactant in aqueous solution.

The maximum bubble pressure technique has been used to study the adsorption kinetics of binary mixtures of an anionic Gemini surfactant C9pPHCNa with a cationic conventional surfactant C10TABr in aqueous solutions. The dynamic surface tension data were analyzed using the revised Ward and Tordai equations as well as the micelle dissociation kinetic model suggested by Joos et al. The apparent diffusion coefficient Da below the cmc, the adsorption barrier epsilona and the micelle dissociation constant kmic were obtained.