bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Aerobic Lactonization of Diols by Biomimetic Oxidation.
Authors: Endo Yoshinori , Baeckvall Jan‐E. 
Published: March 2012

AbstractA variety of diols undergo the biomimetic oxidation with air or molecular oxygen without any side‐reactions or formation of by‐products to give a series of up to nine‐membered lactones.
ChemInform Abstract: Triflic Acid Catalyzed Reductive Coupling Reactions of Carbonyl Compounds with O‐, S‐, and N‐Nucleophiles.
Authors: Gellert Beate A. , Kahlcke Nils , Feurer Markus , Roth Stefanie 
Published: March 2012

AbstractHighly efficient metal‐free reductive coupling reactions of aldehydes and ketones with a range of nucleophiles in the presence of triflic acid as catalyst are presented.
ChemInform Abstract: Intermolecular Coupling of Alkynes with Acrylates by Recyclable Oxide‐Supported Ruthenium Catalysts: Formation of Distorted Ruthenium(IV)‐oxo Species on Ceria as a Key Precursor of Active Species.
Authors: Miura Hiroki , Shimura Shun , Hosokawa Saburo , Yamazoe Seiji , Wada Kenji , Inoue Masashi 
Published: March 2012

AbstractIt is found that treatment of distorted Ru(IV)‐oxo species on ceria or zirconia with HCOONa leads to low‐valent Ru compounds which efficiently promote the coupling of acrylates with some alkynes as well as norbornene.
ChemInform Abstract: Base‐Controlled Selective Conversion of Michael Adducts of Malonates with Enones in the Presence of Iodine.
Authors: Miao Chun‐Bao , Zhang Min , Tian Zong‐Yong , Xi Hai‐Tao , Sun Xiao‐Qiang , Yang Hai‐Tao 
Published: March 2012

AbstractTreatment of malonates of type (I) with iodine can result in efficient formation of trans‐substituted cyclopropanes, oxetanes or α‐hydroxylated derivatives depending on the basic conditions used.
ChemInform Abstract: Diastereocontrol in Asymmetric Allyl—Allyl Cross‐Coupling: Stereocontrolled Reaction of Prochiral Allylboronates with Prochiral Allyl Chlorides.
Authors: Brozek Laura A. , Ardolino Michael J. , Morken James P. 
Published: March 2012

AbstractA simple but highly effective method to establish vicinal stereocenters in a catalytic asymmetric fashion is described.
ChemInform Abstract: Coordination and Catalytic Activity of Ruthenium Complexes Containing Tridentate P,N,O Ligands.
Authors: Lee Chun‐Chin , Chu Wan‐Yi , Liu Yi‐Hong , Peng Shie‐Ming , Liu Shiuh‐Tzung 
Published: March 2012

AbstractSynthesis and characterization of seven ruthenium complexes bearing PNO ligands are reported.
ChemInform Abstract: Development of Decarboxylative Coupling Processes for the Synthesis of Azomethines and Ketones.
Authors: Collet Florence , Song Bingrui , Rudolphi Felix , Goossen Lukas J. 
Published: March 2012

AbstractA three‐component decarboxylative coupling of potassium α‐oxocarboxylates with amines and aldehydes is smoothly achieved in the presence of a Pd—Cu bimetallic catalyst system.
ChemInform Abstract: Palladium‐Catalyzed Decarboxylative Coupling of Isatoic Anhydrides with Arylboronic Acids.
Authors: Lu Wei , Chen Jiuxi , Liu Miaochang , Ding Jinchang , Gao Wenxia , Wu Huayue 
Published: March 2012

AbstractMechanistic experiments using deuterium labeling prove that the O‐atom of the carboxyl group derives from dioxygen after splitting off the carbon dioxide.
ChemInform Abstract: Conjugate Addition of 1,3‐Dicarbonyl Compounds to Maleimides Using a Chiral C2‐Symmetric Bis(2‐aminobenzimidazole) as Recyclable Organocatalyst.
Authors: Gomez‐Torres Eduardo , Alonso Diego A. , Gomez‐Bengoa Enrique , Najera Carmen 
Published: March 2012

AbstractCompared to diketones or β‐ketoesters, dimethyl malonate (XII) produces only 5% of product (XIII).
ChemInform Abstract: A Highly Stereoselective, Modular Route to (E)‐Vinylsulfones and to (Z)‐ and (E)‐Alkenes.
Authors: Braun Marie‐Gabrielle , Quiclet‐Sire Beatrice , Zard Samir Z. 
Published: March 2012

AbstractThe title method is based on the recently discovered radical fragmentation of 2‐fluoro‐6‐pyridinoxy derivatives of vinylsulfones.
ChemInform Abstract: NHC—Pd(II)—Im (NHC = N‐Heterocyclic Carbene; Im = 1‐Methylimidazole) Complexes as Efficient Catalysts for Suzuki—Miyaura Coupling Reactions of Aryl Chlorides.
Authors: Tang Yi‐Qiang , Lu Jian‐Mei , Shao Li‐Xiong 
Published: March 2012

AbstractThe new palladium chloride‐imidazole complex exhibits high catalytic activity in the room‐temperature Suzuki‐Miyaura coupling reactions of aryl chlorides.
ChemInform Abstract: Cobalt‐Catalyzed, Room‐Temperature Addition of Aromatic Imines to Alkynes via Directed C—H Bond Activation.
Authors: Lee Pin‐Sheng , Fujita Takeshi , Yoshikai Naohiko 
Published: March 2012

AbstractA quaternary catalytic cobalt system promotes the hydroarylation of internal alkynes with aromatic imines through chelation‐assisted C—H bond cleavage.
ChemInform Abstract: Domino Friedel—Crafts‐Type Cyclizations of Difluoroalkenes Promoted by the α‐Cation‐Stabilizing Effect of Fluorine: An Efficient Method for Synthesizing Angular PAHs.
Authors: Fuchibe Kohei , Jyono Hideharu , Fujiwara Masaki , Kudo Takao , Yokota Misaki , Ichikawa Junji 
Published: March 2012

AbstractDomino cyclizations of 1,1‐difluoroalkenes are studied with the goal of synthesizing nonlinear polycyclic aromatic hydrocarbons.
ChemInform Abstract: Nickel‐Catalyzed Asymmetric α‐Arylation and Heteroarylation of Ketones with Chloroarenes: Effect of Halide on Selectivity, Oxidation State, and Room‐Temperature Reactions.
Authors: Ge Shaozhong , Hartwig John F. 
Published: March 2012

AbstractNi(cod)2/(R)‐BINAP and Ni(cod)2/(R)‐(Pos) effectively promote the asymmetric α‐arylation/heteroarylation of indanones and tetralones with chloroarenes.
ChemInform Abstract: Palladium‐Catalyzed Pentannulation of Polycyclic Aromatic Hydrocarbons.
Authors: Eversloh Christian Luetke , Avlasevich Yuri , Li Chen , Muellen Klaus 
Published: March 2012

AbstractThe title reaction allows the introduction of single or multiple cyclopentadienide moieties into easily available pyrene, anthracene, and perylene bromides in a feasible one‐step reaction.
ChemInform Abstract: Synthesis of Diverse Spiroisoxazolidinohydantoins by Totally Regio‐ and Diastereoselective 1,3‐Dipolar Cycloadditions.
Authors: Bellucci Maria Cristina , Marcelli Tommaso , Scaglioni Leonardo , Volonterio Alessandro 
Published: March 2012

AbstractTitle compounds are produced from 5‐carboxymethylene hydantoins generated by reaction of carbodiimides and acetylenedicarboxylic acid monoesters under mild conditions.
ChemInform Abstract: Highly Asymmetric Intramolecular Cyclopropanation of Acceptor‐Substituted Diazoacetates by Co(II)‐Based Metalloradical Catalysis: Iterative Approach for Development of New‐Generation Catalysts.
Authors: Xu Xue , Lu Hongjian , Ruppel Joshua V. , Cui Xin , Lopez de Mesa Silke , Wojtas Lukasz , Zhang X. Peter 
Published: March 2012

AbstractA newly synthesized cobalt(II)‐catalyst is effectively used in the asymmetric intramolecular cyclopropanation of various α‐acceptor‐substituted diazoacetates providing oxabicyclo[3.1.0]hexan‐2‐one derivatives with high diastereo‐ and enantioselectivity.
ChemInform Abstract: Highly Selective Nickel‐Catalyzed Methyl‐Carboxylation of Homopropargylic Alcohols for α‐Alkylidene‐γ‐butyrolactones.
Authors: Li Suhua , Ma Shengming 
Published: March 2012

AbstractThe preparation of fused lactones succeeds in good yields with high stereo‐ and regioselectivities.
ChemInform Abstract: Dehydrogenative Heck Reaction of Furans and Thiophenes with Styrenes under Mild Conditions and Influence of the Oxidizing Agent on the Reaction Rate.
Authors: Vasseur Alexandre , Muzart Jacques , Le Bras Jean 
Published: March 2012

AbstractFurans and thiophenes undergo C—H activation with Pd(OAc)2 to give a series of coupling products with styrenes.
ChemInform Abstract: An Alkyne Hydroacylation Route to Highly Substituted Furans.
Authors: Lenden Philip , Entwistle David A. , Willis Michael C. 
Published: March 2012

AbstractThe Rh‐catalyzed reaction of propargylic alcohols with aldehydes being an ‐S‐Me functionality gives γ‐hydroxy‐α,β‐enones which undergo dehydrative cyclization to di‐ and trisubstituted furan structures.
ChemInform Abstract: Highly Diastereoselective Synthesis of 1‐Pyrrolines via SnCl4‐Promoted [3 + 2] Cycloaddition Between Activated Donor—Acceptor Cyclopropanes and Nitriles.
Authors: Sathishkannan Gopal , Srinivasan Kannupal 
Published: March 2012

AbstractThe products are isolated as single cis diastereomers.
ChemInform Abstract: Highly Efficient and Diastereoselective Gold(I)‐Catalyzed Synthesis of Tertiary Amines from Secondary Amines and Alkynes: Substrate Scope and Mechanistic Insights.
Authors: Liu Xin‐Yuan , Guo Zhen , Dong Sijia S. , Li Xiao‐Hua , Che Chi‐Ming 
Published: March 2012

AbstractThe reported Au‐catalyzed synthesis of tertiary amines with a very broad substrate scope can be conducted as a one‐pot reaction from simple and readily available starting materials, without the need of workup and isolation of air/moisture‐sensitive enamine intermediates.
ChemInform Abstract: Palladium Nanoparticles Encapsulated in a Metal—Organic Framework as Efficient Heterogeneous Catalysts for Direct C2 Arylation of Indoles.
Authors: Huang Yuanbiao , Lin Zujin , Cao Rong 
Published: March 2012

AbstractThe catalyst is easily recoverable and reusable several times without leaching and loss of activity.
ChemInform Abstract: Direct Asymmetric Hydrosilylation of Indoles: Combined Lewis Base and Broensted Acid Activation.
Authors: Xiao You‐Cai , Wang Chao , Yao Yuan , Sun Jian , Chen Ying‐Chun 
Published: March 2012

AbstractTrichlorosilane in combination with a chiral Lewis base catalyst allows the asymmetric reduction of unprotected 1H‐indoles to chiral indolines.
ChemInform Abstract: Rhodium(III)‐Catalyzed Oxidative Carbonylation of Benzamides with Carbon Monoxide.
Authors: Du Ya , Hyster Todd K. , Rovis Tomislav 
Published: March 2012

AbstractAn efficient strategy for the oxidative carbonylation of aromatic amides (I) and (IV) via C—H/N—H activation to form phthalimides using an Rh(III) catalyst is described.
ChemInform Abstract: Ruthenium Diacetate‐Catalyzed Oxidation Alkenylation of C—H Bonds in Air: Synthesis of Alkenyl N‐Arylpyrazoles.
Authors: Arockiam Percia B. , Fischmeister Cedric , Bruneau Christian , Dixneuf Pierre H. 
Published: March 2012

AbstractThe first examples of an oxidative alkenylation of N‐arylpyrazoles by cooperative action of a Ru(III) catalyst and acetate ligands in air are described.
ChemInform Abstract: Ring Lithiation and Functionalization of Imidazol‐2‐ylidene‐boranes.
Authors: Solovyev Andrey , Lacote Emmanuel , Curran Dennis P. 
Published: March 2012

AbstractA double functionalization at both C‐4 and C‐5 of substrates (I) is possible in either one or two steps to produce derivatives which are of interest as catalysts or complexation agents.
ChemInform Abstract: Palladium‐Catalyzed Intramolecular Sulfonamidation/Oxidation of Imines: Access to Multifunctional Benzimidazoles.
Authors: Fu Shaomin , Jiang Huanfeng , Deng Yuanfu , Zeng Wei 
Published: March 2012

AbstractA convenient method to prepare various benzimidazoles is reported.
ChemInform Abstract: Copper‐Catalyzed, One‐Pot, Three‐Component Synthesis of Benzimidazoles by Condensation and C—N Bond Formation.
Authors: Kim Yong , Kumar Rajesh , Park Namjin , Heo Yumi , Lee Sunwoo 
Published: March 2012

AbstractIt allows an efficient access to a wide range of benzimidazoles and related compounds.
ChemInform Abstract: Amphiphilic Allylation of Arylidene‐1,3‐oxazol‐5(4H)‐one Using Bis‐π‐allylpalladium Complexes: An Approach to Synthesis of Cyclohexyl and Cyclohexenyl α‐Amino Acids.
Authors: Genady Afaf R. , Nakamura Hiroyuki 
Published: March 2012

AbstractThe bis‐allylation of activated azlactones proceeds via a three‐component assembling reaction between azlactones (I), allyl acetate (II), and allyltrifluoroborate (III) in the presence of a palladium catalyst, thus avoiding toxic allylstannanes.
ChemInform Abstract: Highly Dispersed Silica‐Supported Nanocopper as an Efficient Heterogeneous Catalyst: Application in the Synthesis of 1,2,3‐Triazoles and Thioethers.
Authors: Veerakumar Pitchaimani , Velayudham Murugesan , Lu Kuang‐Lieh , Rajagopal Seenivasan 
Published: March 2012

AbstractThe new nanocatalyst consisting of copper nanoparticles supported on amine modified silica is fully characterized and serves as an efficient heterogeneous catalyst for the synthesis of disubstituted triazoles and thioethers.
ChemInform Abstract: Cu(II) Catalyzed Imine C—H Functionalization Leading to Synthesis of 2,5‐Substituted 1,3,4‐Oxadiazoles.
Authors: Guin Srimanta , Ghosh Tuhin , Rout Saroj Kumar , Banerjee Arghya , Patel Bhisma K. 
Published: March 2012

AbstractBenzohydrazides derived from aliphatic aldehydes decompose.
ChemInform Abstract: Accelerating Lead Optimization of Chromone Carboxamide Scaffold Throughout Microwave‐Assisted Organic Synthesis.
Authors: Cagide Fernando , Reis Joana , Gaspar Alexandra , Borges Fernanda 
Published: March 2012

AbstractTreatment of chromone‐2‐carboxylic acid with POCl3 and subsequent microwave‐assisted reaction of the acyl chloride with aniline derivatives offers a convenient access to the biologically important targets.
ChemInform Abstract: The Synthesis of Xanthones, Xanthenediones, and Spirobenzofurans: Their Antibacterial and Antifungal Activity.
Authors: Omolo Justin J. , Johnson Myron M. , van Vuuren Sandy F. , de Koning Charles B. 
Published: March 2012

AbstractThe compounds (II)—(V), (VII), and (VIII) and the previously synthesized compound (IX) are tested for their antimicrobial activity.
ChemInform Abstract: Thermally Induced Skeletal Rearrangement of (Z)‐O‐Propargylic α,β‐Unsaturated Aldoximes to Multisubstituted Pyridine Oxides.
Authors: Nakamura Itaru , Zhang Dong , Terada Masahiro 
Published: March 2012

AbstractA novel synthesis of the important pyridine structures proceeds through thermal [2,3] rearrangement followed by 4π electrocyclization and ring enlargement.
ChemInform Abstract: A Highly Efficient and Enantioselective Access to Tetrahydroisoquinoline Alkaloids: Asymmetric Hydrogenation with an Iridium Catalyst.
Authors: Chang Mingxin , Li Wei , Zhang Xumu 
Published: March 2012

AbstractThe iridium hydrido complex in combination with elemental iodine allows the preparation of tetrahydro derivatives with high levels of enantioselectivity.
ChemInform Abstract: An Efficient Approach to Pyrazolo[5,1‐a]isoquinolin‐2‐amines via a Silver(I)‐Catalyzed Three‐Component Reaction of 2‐Alkynylbenzaldehyde, Sulfonohydrazide, and Nitrile.
Authors: Yu Xingxin , Yang Qin , Lou Honglei , Peng Yiyuan , Wu Jie 
Published: March 2012

AbstractA three‐component cascade cyclization strategy provides access to the title compounds (III), (V), (VII), and (VIII) in good to excellent yields under mild conditions.
ChemInform Abstract: Microwave‐Assisted One‐Pot Synthesis of 2‐Aryl‐5,6‐dihydro‐4H‐1,3‐thiazines via Reaction Between Lawesson′s Reagent and Allyl Arylamides Derived from Morita—Baylis—Hillman Acetates.
Authors: Bhowmik Subhendu , Mishra Amita , Batra Sanjay 
Published: March 2012

AbstractA new methodology to access thiazines is developed.
ChemInform Abstract: One Pot Synthesis of cis‐Bispyrimidodiazepinone Derivatives via Low‐Valent Titanium Reagent (TiCl4/Sm).
Authors: Dou Guolan , Shi Daqing 
Published: March 2012

AbstractThe title derivatives (III) and (V) are readily obtained by the reaction of bis(benzylidene)propanediamines (I) and (IV) with triphosgene (II) via a low‐valent titanium reagent.
ChemInform Abstract: Synthesis of Amino‐benzothiaoxazepine‐1,1‐dioxides Utilizing a Microwave‐Assisted, SNAr Protocol.
Authors: Organ Michael G. , et al. et al. 
Published: March 2012

AbstractDesign and synthesis of a 126‐membered library of amino‐benzothiaoxazepine‐1,1‐dioxides via microwave‐assisted aromatic substitution reactions are described.
ChemInform Abstract: Enantioselective Phospha‐Michael Reaction of Diphenyl Phosphonate with Nitroolefins Utilizing Conformationally Flexible Guanidinium/Bisthiourea Organocatalyst: Assembly‐State Tunability in Asymmetric Organocatalysis.
Authors: Sohtome Yoshihiro , Horitsugi Natsuko , Takagi Rika , Nagasawa Kazuo 
Published: March 2012

AbstractThe organocatalyst (GBT) efficiently promotes the asymmetric addition of the phosphonate (II) to nitroolefins giving β‐nitrophosphonates in high optical purity.
ChemInform Abstract: Highly Enantioselective Hydrogenation of β‐Acyloxy and β‐Acylamino α,β‐Unsaturated Phosphonates Catalyzed by Rhodium Phosphane‐Phosphite Complexes.
Authors: Chavez M. Angeles , Vargas Sergio , Suarez Andres , Alvarez Eleuterio , Pizzano Antonio 
Published: March 2012

AbstractThe Rh complex (RPO) efficiently promotes the asymmetric hydrogenation of title phosphonates giving synthetically and biologically important β‐functionalized phosphonates in high optical purity.
ChemInform Abstract: Copper(II) Triflate: A Versatile Catalyst for the One‐Pot Preparation of Orthogonally Protected Glycosides.
Authors: Tran Anh‐Tuan , Jones Rachel A. , Pastor Julien , Boisson Julien , Smith Nichola , Galan M. Carmen 
Published: March 2012

AbstractUnder these conditions two and three one‐pot transformations are possible.
Anticancer Activity of Silver–N‐Heterocyclic Carbene Complexes: Caspase‐Independent Induction of Apoptosis via Mitochondrial Apoptosis‐Inducing Factor (AIF)
Authors: Eloy Laure , Jarrousse Anne‐Sophie , Teyssot Marie‐Laure , Gautier Arnaud , Morel Laurent , Jolivalt Claude , Cresteil Thierry , Roland Sylvain 
Published: March 2012

AbstractFourteen silver(I) complexes bearing N‐heterocyclic carbene (NHC) ligands were prepared and evaluated for anticancer activity. Some of these were found to exhibit potent antiproliferative activity toward several types of human cancer cell lines, including drug‐resistant cell lines, with IC50 values in the nanomolar range. An initial investigation into the mechanism of cell death induced by this family of silver(I) complexes was carried out. Cell death was shown to result from the activation of apoptosis without involvement of primary necrosis. In HL60 cells, silver–NHCs induce depolarization of the mitochondrial membrane potential (ΔΨm) and likely allow the release of mitochondrial proteins to elicit early apoptosis. This effect is not related to the overproduction of reactive oxygen species (ROS). In addition, apoptosis is not associated with the activation of caspase‐3, but is triggered by the translocation of apoptosis‐inducing factor (AIF) and caspase‐12 from mitochondria and the endoplasmic reticulum, respectively, into the nucleus to promote DNA fragmentation and ultimately cell death. No modification in cell‐cycle distribution was observed, indicating that silver–NHCs are not genotoxic. Finally, the use of a fluorescent complex showed that silver–NHCs target mitochondria. Altogether, these results demonstrate that silver–NHCs induce cancer cell death independent of the caspase cascade via the mitochondrial AIF pathway.
Discovery of N‐Arylalkyl‐3‐hydroxy‐4‐oxo‐3,4‐dihydroquinazolin‐2‐carboxamide Derivatives as HCV NS5B Polymerase Inhibitors
Authors: Deore Ravindra Ramesh , Chen Grace Shiahuy , Chang Pei‐Teh , Chern Ting‐Rong , Lai Shin‐Yu , Chuang Ming‐Hsieh , Lin Jung‐Hsin , Kung Fan‐Lu , Chen Chien‐Shu , Chiou Chun‐Tang , Chern Ji‐Wang 
Published: March 2012

AbstractThe metal ion chelating β‐N‐hydroxy‐γ‐ketocarboxamide pharmacophore was integrated into a quinazolinone scaffold, leading to N‐arylalkyl‐3‐hydroxy‐4‐oxo‐3,4‐dihydroquinazolin‐2‐carboxamide derivatives as hepatitis C virus (HCV) NS5B polymerase inhibitors. Lead optimization led to the identification of N‐phenylpropyl carboxamide 9 k (IC50=8.8 μM). Compound 9 k possesses selectivity toward HCV1b replicon Ava.5 cells (EC50=17.5 μM) over parent Huh‐7 cells (CC50=187.5 μM). Compound 9 k effects a mixed mode of NS5B inhibition, with NTP‐competitive displacement properties. The interaction between 9 k and NS5B is stabilized by the presence of magnesium ions. Docking studies showed that the binding orientation of 9 k occupies the central portions of both magnesium‐mediated and NTP‐ribose‐response binding sites within the active site region of NS5B. As a result, 3‐hydroxy‐4‐oxo‐3,4‐dihydroquinazolin‐2‐carboxamide derivatives are disclosed herein as novel, mainly active site inhibitors of HCV NS5B polymerase.
Organic Reactions in Ionic Liquids Studied by in Situ XPS
Authors: Niedermaier Inga , Kolbeck Claudia , Taccardi Nicola , Schulz Peter S. , Li Jing , Drewello Thomas , Wasserscheid Peter , Steinrück Hans‐Peter , Maier Florian 
Published: March 2012

AbstractWe demonstrate the application of in situ X‐ray photoelectron spectroscopy (XPS) to monitor organic, liquid‐phase reactions. By covalently attaching ionic head groups to the reacting organic molecules, their volatility can be reduced such that they withstand ultra high vacuum conditions. The applied method, which is new for the investigation of organic reactions, allows for following the fate of all elements present in the reaction mixture—except for hydrogen—in a quantitative and oxidation‐state‐sensitive manner in one experiment. This concept is demonstrated for the alkylation of a tertiary amine attached to an imidazolium or phosphonium moiety by the anion 4‐chlorobutylsulfonate ([ClC4H8SO3]−). In the course of the reaction, the covalently bound chlorine is converted to chloride and the amine to ammonium as reflected by the distinct shifts in the N 1s and Cl 2p binding energies.
Synthesis and Toxicology of p‐Phosphonic Acid Calixarenes and O‐Alkylated Analogues as Potential Calixarene‐Based Phospholipids
Authors: Martin Adam D. , Houlihan Emma , Morellini Natalie , Eggers Paul K. , James Eliza , Stubbs Keith A. , Harvey Alan R. , Fitzgerald Melinda , Raston Colin L. , Dunlop Sarah A. 
Published: March 2012

AbstractA series of p‐phosphonic acid calix[n]arenes 1 a–g bearing hydroxy groups, n=4 and 5, or alkyl chains of varying lengths at their lower rim, n=4, were synthesised, and in vitro assessments of their effect on cell viability in rat PC12 cells and primary cultures of mixed retinal cells were conducted. Compounds 1 a and 1 g, bearing hydroxy groups at their lower rim, displayed lower toxicity towards PC12 cells than their alkylated counterparts; concentrations of up to 1 mg mL−1 did not affect the number of viable cells. Mixed retinal cultures showed a higher susceptibility towards toxic effects for all calixarenes tested. Compound 1 b self‐assembles into nanofibres from a toluene solution, and 1 c assembles into micelles from an aqueous solution, with these nanoscale architectures showing potential applications for various biological roles, such as solubilising p‐nitrophenol and curcumin.
A localization strategy based on n‐times trilateral centroid with weight
Authors: Qiu Tie , Zhou Yu , Xia Feng , Jin Naigao , Feng Lin 
Published: March 2012

SUMMARYLocalization based on received signal strength indication (RSSI) is a low cost and low complexity technology, and it is widely applied in distance‐based localization of wireless sensor networks. The error of existing localization technologies is significant. This paper presents the N‐times trilateral centroid weighted localization algorithm, which can reduce the error considerably. Considering the instability of RSSI, we use the weighted average of many RSSIs as current RSSI. To improve the accuracy, we select a number of (no less than three) reliable beacon nodes to increase the localization times. Then we calculate the distances between reliable beacon nodes and the mobile node using an empirical formula. The mobile node is located N times using the trilateral centroid algorithm. Finally, we take the weighted average of the filtered reference coordinates as the mobile node's coordinates. We conduct experiments with the STM32W108 chip, which supports IEEE 802.15.4. The results show that the proposed algorithm performs better than the trilateral centroid algorithm. Copyright © 2012 John Wiley & Sons, Ltd.