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AbstractIn this paper, we show that if His a Dedekind complete normed Riesz space with the local Egoroff property, then His lattice isomorphic to an ideal of an AM-space if and only if for any order bounded norm null sequence in H. Based on this, several characterizations of discrete Banach lattices with order continuous norms are provided. As an application, we find the special regulator for every relative uniform convergent sequence in discrete Banach lattices with order continuous norms.

Seven unchelated bisphosphine-based allenylidene Pt(II) complexes, including three mono(allenylidene) Pt(II) complexes (3a, 3c–d) and four cis-bis(allenylidene) Pt(II) complexes (4a–d), along with four chelated bisphosphine-based bis(allenylidene) Pt(II) complexes (6b–dand 8), have been developed by using alkynyl triazole salt as the allenylidene source, in which a silver transmetalation reaction of mono(allenylidene) Ag(I)Cl complex 2was involved as the key step. All of these mono- and bis(allenylidene) Pt(II) complexes were fully characterized by NMR spectroscopy and ESI-MS analysis. Moreover, the crystal structures of the unchelated mono(allenylidene) Pt(II) complex 3c, bis(allenylidene) Pt(II) complex 4a, and the chelated bis(allenylidene) Pt(II) complexes 6cand 8were elucidated, revealing a square-planar coordination geometry in 3cand 4a, whereas a slightly twisted square-planar arrangement was observed in 6cand 8. In comparison to unchelated counterparts 3cand 4a, a stronger coordination of Pt(II) with the chelated bisphosphine groups and a weakened Pt–Clcomplexation were observed in complexes 6cand 8. The catalytic prowess of these bisphosphine-bearing mono(allenylidene) Pt(II) complexes was then evaluated in Pt(II)-catalyzed 1,6-enyne cycloisomerization and Pt(II)-mediated bis-indolylation of cyclic vinyl amines/ethers, resulting in the formation of five methylene pyrrolidine derivatives (11a–e), four tri- or tetra-substituted cyclopropane derivatives (12a–d), and four ring-opening products (14a–d).

Pushed by social demands, China has continuously developed its low-medium speed maglev transportation systems in recent decades. However, with the increase of the running mileage of the train, high frequency vibration of suspension frame gradually appears. In this paper, a method to analyze the high frequency vibration of suspension frame by detecting the current of traction motor is proposed. Field measurements of suspension frame vibration and traction motor current of low-medium maglev train were conducted on a maglev line that has been commercially put into operation. The test results show that the speed of the measured maglev train was closely correlated with vibration accelerations of the suspension frame in three directions, but as the speed increased, the influence it imposed on the suspension frame vibration waned. The dominant frequency of traction motor resultant current was consistent with the dominant frequency of the suspension frame vibration acceleration. The switching frequency of traction inverter was the main cause of high frequency vibration of suspension frame.

Bifurcation analysis is studied for the first time in magneto-hydrodynamic (MHD) Jeffery–Hamel flow nanofluids. The dimensionless ordinary differential equations are formulated by using the similarity transformations. The phase portraits of the traveling wave solutions are examined using bifurcation theory on the dynamical system of the considered equation. Moreover, multistability and sensitivity analysis is used to examine quasi-periodic and periodic behavior for various initial conditions. The (MHD) Jeffery–Hamel flow solutions are derived analytically by applying the extended direct algebraic approach and the influence of the different physical parameters for velocity profiles, have been examined. It is found that the physical parameter i.e, Reynolds number and channel angle rising in convergent flow results in an increase in the velocity profiles, signifying that backflow is excluded, while an inverse behavior can be attributed to a diverging flow.

Let E, Fbe Banach lattices, where Ehas the disjoint Riesz decomposition property. For a lattice homomorphism T:E→Fand a bounded subset Aof E, we establish a necessary and sufficient condition under which TAis b-order bounded. Based on this, we study the b-order boundedness of subsets of Eand obtain several characterizations of AM-spaces. Furthermore, we introduce and investigate a novel type of operators referred to as M-serially summing operator. The connections of this category of operators with classical notions of operators, such as majorizing operators, preregular operators and serially summing operators, are considered.

The first example of gold-catalyzed formal intermolecular [4 + 2 + 1] cycloaddition was developed using 1,3-dien-8-yne as C4 and C2 units and diazo ester as the C1 unit, which provides expedient access to a series of structurally complicated [5.3.0] bicyclic adducts in moderate yields with moderate to high diastereoselectivities. The key route involved a cascade process of dienyne cycloisomerization, cyclopropyl gold carbene’s trapping, and subsequent divinyl cyclopropane (DVCP) Cope rearrangement.

A new method was developed to diastereoselectively synthesize polysubstituted 1,2-diamine compounds from the reaction of diazoesters with arylamines and diaryl imines by using the dioxazoline ligand L2-ligated silver catalyst. The Lewis acidity of the silver catalyst affected the different types of substrate diastereoselectivities; It also led to the formation of amine-exchange side products.

A series of axially chiral bis-1,2,3-triazol-5-ylidene Au(I) complexes (R)-8a–gand one mono-1,2,3-triazol-5-ylidene Au(I) complex (R)-9awere prepared from commercially available (R)-binaphthyl-2,2-diamine (BINAM) compound, in which, transmetalation of bis(MIC)-bis[Ag(I)] intermediates to the corresponding Au(I) complexes were employed as the key synthetic step. The structures of these MIC–Au(I) complexes were diversified by using different alkyne reagents in copper catalyzed azide–alkyne cycloaddition (CAAC) step. Three chiral bis-1,2,3-triazol-5-ylidene Ag(I) complexes, (R)-7a, (R)-7c, and (R)-7d, were prepared and fully characterized. On the basis of (R)-7a’s crystal structure, a chiral tetra(MIC)-bis(Ag) structure was exhibited, with two chiral bis-1,2,3-triazol-5-ylidene ligands interconnected by two nearly linear silver atom bridges, of which, significant Ag(I)–Ag(I) bonding existed. The crystal structures of (R)-8a, (R)-8f, and (R)-8gwere also obtained, which exhibit an axially chiral bis(MIC)-bis(Au) structure without Au(I)–Au(I) interaction. Application of these axially chiral bis-/mono- 1,2,3-triazol-5-ylidene Au(I) complexes in the enantioselective [2 + 2] cycloaddition of alleneamides 10awith p-methoxy styrene 11awere explored, in which (R)-8bwith p-methoxy phenyl substituent performed better than other Au(I) complexes. Various substrate scopes, including different alleneamides and mono-, bisubstituted olefins were investigated by using (R)-8b/AgSbF6catalyst combination. It was found that product’s enantioselectivities are highly dependent upon substrate’s structure, especially in the reactions of acyclic allenesulfoamide substrates. Most of the chiral cyclobutane product’s enantioselectivities ranged from 61 to 99% ee. The [2 + 2] cycloaddition of 2,3-dimethylindole 13with alleneamide 10awas also explored by using (R)-8band (R)-8gas the catalyst precursors.

An efficient new method has been developed to synthesize N2-alkyl 1,2,3-triazole products by toluenesulfonic acid (TsOH) catalyzed addition of N1-Ts substituted 1,2,3-triazoles to olefins. The reactions of monosubstituted and unsubstituted triazole substrates with various olefins, including vinyl esters, are explored.

Ubiquitin-specific proteases (USPs) act as proto-oncogenes or tumor suppressors in a wide variety of cancers. In this study, we intended to explore the role of USP1 in hepatocellular carcinoma (HCC).

A convenient new method was developed to prepare unfused polyaromatic furan derivatives from diynyl‐1,6‐diols through a novel base‐catalyzed cascade 1,3‐H shift/cyclization process. Deuterium experiments were performed to determine that the 1,3‐H shift was the rate‐determining step.

Direct radical additions of ethers to terminal alkynes were investigated by using Me2ZnO2as radical initiator to afford 2vinyl ether derivatives with high Eselectivity, while reversed EZselectivity is obtained with Et3BO2. Two competitive pathways are suggested for the formation of vinyl radical B: zincradical exchange route a followed by protonation provides Econfiguration products exclusively through ZnII complexation. Hydrogen abstraction by vinyl radicals route b yields mainly Zisomers.© WileyVCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009

The catalytic application of four monoallenylidene bisphosphine Pd(II) catalysts, which were developed using alkynyl triazole salt as the allenylidene source, in the cycloisomerization of 1,6-enyne was explored. Two divergent reaction pathways, including a new type of intramolecular Alder-ene (IMAE) route and a routine cycloisomerization route, were developed using either complex TAA(Et3P)2-PdCl·BF4–3bor TAA(Ph3P)2-PdCl·BF4–3cas the catalyst precursor.

Two for the price of one: A new tandem reaction involving two consecutive, competitive nucleophilic additions was developed to construct a series of densely functionalized propargylic alcohol derivatives from simple materials without functional protection, in which a variety of electrophiles including cyclopropanone and aromatic aldehydes have been successfully employed. Multiple functionalities in products 1and 2make them versatile structural motifs for further elaboration.

The transient receptor potential vanilloid 1 receptor (TRPV1) is expressed predominantly in a subset of primary afferent nociceptors. Due to its specific anatomical location and its pivotal role as a molecular integrator for noxious thermal and chemical stimuli, there is considerable interest to develop TRPV1 antagonists for the treatment of pain. Recently, N-(4-chlorobenzyl)-N'-(4-hydroxy-3-iodo-5-methoxybenzyl) thiourea (IBTU) was synthesized, and it was found in vitro to be a high-affinity competitive antagonist of cytoplasmic, but not intracellular, TRPV1. In this study, we examined the in vivo antinociceptive activity of IBTU in several acute and inflammatory pain models in mice. Our emphasis was on nociceptive pathways that are likely mediated by TRPV1, including capsaicin-, noxious heat-, and proton (including inflammation)-induced nociception tests. Capsazepine was used as a positive control in these experiments. IBTU dose-dependently blocked the capsaicin-induced nociception, confirming its antagonism at TRPV1 in vivo. By itself, IBTU produced significant antinociception, because it significantly prolonged the tail-flick latency in a dose-dependent manner. IBTU also blocked both early and late phases of the formalin-induced flinching response as well as acetic acid-induced writhing behavior. Moreover, IBTU inhibited the complete Freund's adjuvant-induced persistent hyperalgesia. Taken together, these data demonstrate that IBTU acts as a TRPV1 antagonist in vivo, and they suggest that it may be of therapeutic use for the treatment of pain.

A new Lewis acid, Zn(ODf)₂, was first prepared from commercially available 3,3,4,4-tetrafluoro[1,2]oxathietane 2,2-dioxide in four steps with 56% yields and also was applied to catalyze highly enantioselective alkynylation of aldehydes in the presence of ligand (1S,2S)-3-(tert-butyldimethylsilyloxyl)-2-N,N-dimethylamino-1-(p-nitrophenyl)propane-1-ol or ligand (−)-N-methylephedrine to afford the corresponding propargylic alcohols in high yields with up to 99% ee.

A new inexpensive chiral amino alcohol-based ligand, (1S,2S)-2-N,N-dimethylamino-1-(p-nitrophenyl)-3-(t-butyldimethylsilyloxy)propane-1-ol, was developed for the asymmetric alkynylation of aliphatic and aromatic aldehydes, to prepare the corresponding propargylic alcohols in high yields with up to 99% ee.

The Au‐catalyzed treatment of alleneamides with electron‐rich alkenes allows an efficient access to functionalized cyclobutanes.

In the presence of AuCl(PPh3)/AgSbF6, 1,4‐allylic diols of type (I) undergo new ring expansion giving one‐carbon higher keto homologues such as (II).

The cyclization of allylic acetates of type (I) and several structurally related analogues affords benzocyclohexanes in generally good yields.

The tandem process using base‐catalyzed 1,3‐H shift as the starting step is applicable to symmetrical aryl diynes (I) as well as unsymmetrical ones.

A simple, new, and highly stereoselective method to prepare multifunctionalized 3‐vinylcyclohexanols and oxabicyclooctanones like (III) is reported.

Internal propargylic alcohols provide bicyclic derivatives which are generally formed as a single diastereomer.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

For Abstract see ChemInform Abstract in Full Text.