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2,3-Disubstituted benzo[6]furans are readily prepared under very mild reaction conditions by the palladium/copper-catalyzed cross-coupling of o-iodoanisole and terminal alkynes, followed by electrophilic cyclization using 12, Br2, PhSeCl and /?-02NC6H4SCl. Aryland vinylic-substituted alkynes undergo electrophilic cyclization in excellent yields. Biologically important furopyridines can be prepared by this approach in high yields. Introduction The benzo[e]furan nucleus is prevalent in a wide variety of biologically active natural and unnatural compounds.1 Many 2-arylbenzofuran derivatives are well known to exhibit a broad range of biological activities, such as anticancer,2 antiproliferative,3 antiviral,4 antifungal,5 immunosuppressive,6 antiplatelet,7 antioxidative,8 insecticidal,9 anti­ inflammatory,10 antifeedant,11 and cancer preventative activity.12 These compounds are also important calcium blockers13 and phytoestrogens.14 For instance, XH-1415 was the first

The design and optimization of a novel trans-1,4-dioxycyclohexane GPR119 agonist series is described. A lead compound 21 was found to be a potent and efficacious GPR119 agonist across species, and possessed overall favorable pharmaceutical properties. Compound 21 demonstrated robust acute and chronic regulatory effects on glycemic parameters in the diabetic or non-diabetic rodent models.

The design and synthesis of novel 1a,2,5,5a-tetrahydro-1H-2,3-diaza-cyclopropa[a]pentalen-4-carboxamide CB2 selective ligands for the potential treatment of pain is described. Compound (R,R)-25 has good balance between CB2 agonist potency and selectivity over CB1, and possesses overall favorable pharmaceutical properties. It also demonstrated robust in vivo efficacy mediated via CB2 activation in the rodent models of inflammatory and osteoarthritis pain after oral administration.

The enantiomeric separations of highly hydrophobic isochromene derivatives were performed and optimized using cyclodextrin-modified micellar capillary electrophoresis. Hydroxypropyl-γ-cyclodextrin proved to be the most effective chiral selector for the enantioseparation of these analytes. The effects of cyclodextrin and sodium dodecyl sulfate concentration and organic modifier were examined in order to optimize the separation conditions. Addition of an organic solvent modifier to the run buffer served to increase the analyte' solubility and enhance the separation efficiency. A highly acidic pH was necessary to effectively suppress the electroosmotic flow when operating in the reverse polarity mode.

[reaction: see text] 2,3-Disubstituted benzo[b]furans are readily prepared under very mild reaction conditions by the palladium/copper-catalyzed cross-coupling of various o-iodoanisoles and terminal alkynes, followed by electrophilic cyclization with I2, PhSeCl, or p-O2NC6H4SCl. Aryl- and vinylic-substituted alkynes undergo electrophilic cyclization in excellent yields. Biologically important furopyridines can be prepared by this approach in high yields.

Twenty chiral isochromene derivatives have been chromatographed on native and derivatized cyclodextrin stationary phases using HPLC. The most effective CSPs for the enantioresolution of these analytes in the reverse phase mode are the hydroxypropyl-β-cyclodextrin (Cyclobond RSP), the 2,3-dimethyl-β-cyclodextrin (Cyclobond DM), and the γ-cyclodextrin (Cyclobond II) stationary phases. The α-cyclodextrin (Cyclobond III), β-cyclodextrin (Cyclobond I), acetyl-β-cyclodextrin (Cyclobond AC), S-1-naphthylethyl carbamate-β-cyclodextrin (Cyclobond SN), and 3,5-dimethylphenyl carbamate-β-cyclodextrin (Cyclobond DMP) stationary phases also show enantioselectivities for some analytes. No enantioseparations were observed in the polar organic mode and only a few separations were found in the normal phase mode. The Cyclobond RSP CSP provided the best overall separations of these analytes in the reverse phase mode. The pH of the mobile phase and the nature of organic modifiers have little effect on the enantioresolution. The substituents on the isochromene ring greatly affect the chiral recognition.

A series of 5-fluoro-4,6-dialkoxypyrimidine GPR119 modulators were discovered and optimized for in vitro agonist activity. A lead molecule was identified that has improved agonist efficacy relative to our clinical compound (APD597) and possesses reduced CYP2C9 inhibitory potential. This optimized lead was found to be efficacious in rodent models of glucose control both alone and in combination with a Dipeptidyl peptidase-4 (DPP-4) inhibitor.

A total synthesis of the naturally occurring hydroxy ketone PEIPC 1, a compound that plays a role in endothelial activation in atherosclerosis, has been completed via a triply convergent preparation of a protected EI derivative 13 from 3,5-diacetoxycyclopentene 7, pentane-1,5-diol, and vinyllithium, using Sharpless epoxidation and enzymatic resolution as key steps. Final coupling with lyso-PC 16 and silyl group deprotection gave PECPC 2 and PEIPC 1, which showed the same activity as natural PECPC and PEIPC. [reaction: see text]

In order to eliminate the shortcomings in apple color grading, such as the slow speed, the large error, a novel fast intelligent grading method is presented, which is based on the improved particle swarm optimization (PSO) algorithm and Support Vector Machine. The main process is to acquire the colority of apple surface by the computer vision technology and extract its features which used as the samples to train SVM. In this method the intelligent PSO algorithm is used to select the optimal parameters of kernel function in support vector machine to improve the classifier's performance, finally grade the apple color with the trained SVM. The actual application shows that the method can achieves high precision, and get very fast grading speed. In apple color grading, the application effect is very notable.

2,3-Disubstituted benzo[b]thiophenes are readily prepared in excellent yields under very mild reaction conditions by the Pd/Cu-catalyzed cross-coupling of commercially available o-iodothioanisole and terminal alkynes, followed by electrophilic cyclization by I2, Br2, NBS, p-O2NC6H4SCl or PhSeCl.

2,3-Disubstituted benzo[b]thiophenes are readily prepared in excellent yields under very mild reaction conditions by the Pd/Cu-catalyzed cross-coupling of commercially available o-iodothioanisole and terminal alkynes, followed by electrophilic cyclization by I2, Br2, NBS, p-O2NC6H4SCl or PhSeCl.

2,3-Disubstituted benzo[b]thiophenes have been prepared in excellent yields via coupling of terminal acetylenes with commercially available o-iodothioanisole in the presence of a palladium catalyst and subsequent electrophilic cyclization of the resulting o-(1-alkynyl)thioanisole derivatives. I2, Br2, NBS, p-O2NC6H4SCl, and PhSeCl have been utilized as electrophiles. Aryl-, vinyl-, and alkyl-substituted terminal acetylenes undergo this coupling and cyclization to produce excellent yields of benzo[b]thiophenes. (Trimethylsilyl)acetylene also undergoes this coupling/cyclization process with I2, NBS, and the sulfur and selenium electrophiles to afford the corresponding 2-(trimethylsilyl)benzo[b]thiophenes. However, cyclization of the silyl-containing thioanisole using Br2 affords 2,3-dibromobenzo[b]thiophene.

Nowadays enterprises are facing more and more uncertainties and challenges. As an important research topic, the enterprise system evolution should be paid more attention by researchers and managers. In this work, we focus on the evolutionary paths of enterprise system, which can determine enterprisepsilas sustainable development. Based on prior research, we combine two theories insights: complex adaptive systems (CAS) theory and resource-based theory (RBT) to develop a conceptual model for enterprise system evolution. Firstly, we analyze the theoretical basis of the enterprise system evolution. Secondly, we present four stages of the enterprise system development and evolution. Lastly, we identify three evolutionary paths of enterprise system, including self-development, dynamic imitation, and innovational emergence.

Residual current protective devices play an important role in electrical safety engineering. Under normal conditions, it is discovered that there exists leakage current during power transmission and it can change dramatically due to insulation fault or electrical shocks. Possible reasons for leakage current in power system are analyzed. Efforts have been made to monitor such leakage current. A residual current relay based on DeviceNet fieldbus is designed. Its controller, drive circuit and DeviceNet interface are introduced. The relay is connected to Rockwell NetLinx network. Despite of its monitoring function on the filed, the measured values are transmitted to the monitor workstation for recording and analysis. The result shows its reliable communication and perfect performance.

Biologically interesting fluoren-9-one and xanthen-9-one derivatives have been prepared by a novel aryl to imidoyl palladium migration, followed by intramolecular arylation. The fluoren-9-one synthesis appears to involve both a palladium migration mechanism and a C-H activation process proceeding through an unprecedented organopalladium(IV) hydride intermediate. The results from deuterium labeling experiments are consistent with the proposed dual mechanism.

The aim of higher education is to cultivate adaptive compound talent. And the classroom-teaching quality has profound social effect. Therefore, there exists practical significance to analyze systematically the factors of classroom-teaching quality and evaluate it. This paper presents a classroom-teaching quality system based on system engineering theory and method, in which we use AHP (analytic hierarchy process) to quantitatively evaluation and analysis the classroom-teaching quality. And we present some suggestions about classroom-teaching quality

Through analyzing the model about the multi-dimension Data warehouse of medical waste management, this paper concludes the general concepts, methods and steps to design multi-dimensional Data Warehouse. And it also gives an case study of a star-shape model of data analysis which suit for medical waste management in one city to explain its realization.

[reaction: see text] 3-Iodoindoles have been prepared in excellent yields by coupling terminal acetylenes with N,N-dialkyl-o-iodoanilines in the presence of a Pd/Cu catalyst, followed by an electrophilic cyclization of the resulting N,N-dialkyl-o-(1-alkynyl)anilines using I2 in CH2Cl2. Aryl-, vinylic-, alkyl-, and silyl-substituted terminal acetylenes undergo this process to produce excellent yields of 3-iodoindoles. The reactivity of the carbon-nitrogen bond cleavage during cyclization follows the following order: Men-Bu, MePh, and cyclohexylMe. Subsequent palladium-catalyzed Sonogashira, Suzuki, and Heck reactions of the resulting 3-iodoindoles proceed smoothly in good yields.

Highly substituted oxygen heterocycles can be prepared in good yields at room temperature by reacting o-(1-alkynyl)-substituted arene carbonyl compounds with NBS, I(2), ICl, p-O(2)NC(6)H(4)SCl, or PhSeBr and various alcohols or carbon-based nucleophiles. Naphthyl ketones and iodides are readily prepared by the reaction of 2-(1-alkynyl)arene-carboxaldehydes with I(2) and simple olefins or alkynes.

[reaction: see text] A wide variety of N-alkyl-3-iodoindoles are readily prepared under very mild reaction conditions by the palladium/copper-catalyzed cross-coupling of N,N-dialkyl-o-iodoanilines and terminal alkynes, followed by electrophilic cyclization by I(2)(). Alkyl-, aryl-, and vinylic-substituted alkynes all undergo iodocyclization in excellent yields.

2,3-Disubstituted benzo[b]thiophenes have been prepared in excellent yields via coupling of terminal acetylenes with commercially available o-iodothioanisole in the presence of a palladium catalyst and subsequent electrophilic cyclization of the resulting o-(1-alkynyl)thioanisole derivatives. I(2), Br(2), NBS, p-O(2)NC(6)H(4)SCl, and PhSeCl have been utilized as electrophiles. Aryl-, vinyl-, and alkyl-substituted terminal acetylenes undergo this coupling and cyclization to produce excellent yields of benzo[b]thiophenes. (Trimethylsilyl)acetylene also undergoes this coupling/cyclization process with I(2), NBS, and the sulfur and selenium electrophiles to afford the corresponding 2-(trimethylsilyl)benzo[b]thiophenes. However, cyclization of the silyl-containing thioanisole using Br(2) affords 2,3-dibromobenzo[b]thiophene.