bluuebunny/crossref_metadata_2025 huggingface dataset:
Direct Coupling Reactions of Alkynylsilanes Catalyzed by Palladium(II) Chloride and a Di(2‐pyridyl)methylamine‐Derived Palladium(II) Chloride Complex in Water and in NMP
Authors: Gil‐Moltó Juan , Nájera Carmen
Published: September 2006

Symmetrical internal alkynes can be prepared either by diarylation of mono‐ and bis(trimethylsilyl)acetylene (TMSA and BTMSA) catalyzed by ligand‐less palladium(II) chloride or by a di(2‐pyridyl)methylamine‐derived palladium(II) chloride complex 1 (typical 0.1–1 mol % of Pd loading) in water using pyrrolidine as base and tetra‐n‐butylammonium bromide as additive. Alternatively, this same process is performed in NMP in the presence of tetra‐n‐butylammonium acetate (TBAA) as base with even lower Pd loadings (0.001–1 mol % Pd). The same reaction conditions are applied to the synthesis of unsymmetrical internal alkynes by monoarylation of silylated terminal alkynes. Aryl iodides can be coupled with TMSA, BTMSA and silylated terminal alkynes under heating or at room temperature, whereas for aryl bromides couplings are performed under water reflux or at 110 °C in the case of NMP. Complex 1 can be reused during several cycles either in water or in NMP without loss of catalytic activity. These simple reaction conditions allow the preparation of internal alkynes without secondary products, most probably by succesive protiodesilylation‐Sonogashira coupling.
A Convenient and Highly Productive Aminohydroxylation Protocol Employing an Osmium‐Diamine Catalyst
Authors: Muñiz Kilian , Almodovar Iriux , Streuff Jan , Nieger Martin
Published: September 2006

In situ generated osmium‐diamine chelates from 2,3‐diaminopropionic acid or diaminosuccinic acid represent efficient catalysts for the highly productive aminohydroxylation of alkenes. The reaction can be employed with various osmium salts and successful catalyst recycling was demonstrated for a representative example. The catalyst design derives from the general structural features of recently investigated osmium complexes from alkene diamination reactions.
Highly Enantioselective Catalytic Alkynylation of Ketones – A Convenient Approach to Optically Active Propargylic Alcohols
Authors: Lu Gui , Li Xingshu , Li Yue‐Ming , Kwong Fuk Yee , Chan Albert S. C.
Published: September 2006

The development of highly enantioselective catalysts involving Cu(OTf)2 and chiral camphorsulfonamides for the alkynylation of ketone is described. The influences of Lewis acids, reaction conditions and chiral ligands on the outcome of the reaction are discussed. The best enantioselectivity (up to 97 % ee) was obtained in the alkynylation of 2′‐chloroacetophenone. The scope of the reaction is also examined.
Recyclable Selective Palladium‐Catalyzed Synthesis of Five‐, Six‐ or Seven‐Membered Ring Lactones and Lactams by Cyclocarbonylation in Ionic Liquids
Authors: Ye Fangguo , Alper Howard
Published: September 2006

The ionic liquids, BMIM PF6 or BMIM NTf2, are used successfully for the palladium‐catalyzed cyclocarbonylation of 2‐allylphenols and anilines, 2‐vinylphenols, and 2‐aminostyrenes. The reaction proceeds cleanly and efficiently to afford high yields of lactones or lactams with good or excellent selectivity for one isomer. The ionic liquid containing the palladium catalyst, and ligand, is recyclable in all cases.
Organocatalytic and Stereoselective [3 + 2] Cycloadditions of Azomethine Imines with α,β‐Unsaturated Aldehydes
Authors: Chen Wei , Yuan Xiang‐Hong , Li Rui , Du Wei , Wu Yong , Ding Li‐Sheng , Chen Ying‐Chun
Published: September 2006

Bipyrazolidin‐3‐one derivatives are biologically significant compounds and their importance has increased in the past decades. In this paper, the first stereoselective [3 + 2] dipolar cycloadditions of azomethine imines with α,β‐unsaturated aldehydes catalyzed by readily available α,α‐diarylprolinol salts are reported, providing a facile route to the synthesis of various chiral bipyrazolidin‐3‐one derivatives under mild conditions. The organocatalyst 1 g with strongly electron‐withdrawing groups exhibited the best stereoselectivity (exo:endo up to 98:2, for exo product up to 97 % ee), in the combination with trifluoroacetic acid.
Efficient Enantioselective Hydrosilylation of Aryl Ketones Catalyzed by a Chiral BINAP‐Copper(I) Catalyst‐Phenyl(methyl)silane System
Authors: Issenhuth Jean Thomas , Dagorne Samuel , Bellemin‐Laponnaz Stéphane
Published: September 2006

The Cu(I)‐chiral diphosphine (BINAP) system was found to efficiently catalyze the hydrosilylation of aryl alkyl ketones with excellent enantioselectivities by using phenyl(methyl)silane as stoichiometric hydride source.
An Efficient Intramolecular Stetter Reaction in Room Temperature Ionic Liquids Promoted By Microwave Irradiation
Authors: Zhou Zhong‐Zhen , Ji Feng‐Qing , Cao Min , Yang Guang‐Fu
Published: September 2006

This communication describes the first report of a microwave‐assisted intramolecular Stetter reaction using imidazolium‐type room temperature ionic liquids (RTILs) as solvents, with thiazolium salts and Et3N as catalysts. The features such as good to excellent yields, shorter reaction time (5–20 min), and recyclable and reusable ionic liquid and catalyst make this method an environmentally benign and highly efficient procedure for the preparation of chromanone derivatives.
An Efficient Bismuth(III) Chloride‐Catalyzed Synthesis of 1,1‐Diarylalkenes via Friedel–Crafts Reaction of Acyl Chloride or Vinyl Chloride with Arenes
Authors: Sun Hongbin , Hua Ruimao , Chen Songjie , Yin Yingwu
Published: September 2006

In the presence of catalytic amount of bismuth(III) chloride, the reactions of acyl chlorides or vinyl chlorides with arenes afforded 1,1‐diarylalkenes in 25–82 % isolated yield. In the case of the reaction of acyl chlorides with arenes, the procedure includes an initial Friedel–Crafts acylation, subsequent formation of vinyl chlorides and final Friedel–Crafts‐type vinylation of another arene molecule with vinyl chloride. This paper reports the first Lewis acid‐catalyzed cleavage of the CCl bond of vinyl chloride and its application in the synthesis of multiply subtituted alkenes.
From a Racemate to a Single Enantiomer: Deracemization by Stereoinversion
Authors: Gruber Christian C. , Lavandera Iván , Faber Kurt , Kroutil Wolfgang
Published: September 2006

The stereoinversion of one enantiomer into its mirror‐image counterpart within a racemate furnishes a single stereoisomeric product in 100 % theoretical yield. This extremely efficient type of deracemization, whereby substrate and product possess an identical chemical structure, can be achieved by using bio‐ or chemo‐catalysts or combinations thereof and is applicable to secondary alcohols, amines and α‐substituted carboxylic acids. Special emphasis is devoted to the theoretical background of the one‐pot, single‐step deracemization of sec‐alcohols.
New Heterogenized Gold(I)‐Heterocyclic Carbene Complexes as Reusable Catalysts in Hydrogenation and Cross‐Coupling Reactions
Authors: Corma A. , Gutiérrez‐Puebla E. , Iglesias M. , Monge A. , Pérez‐Ferreras S. , Sánchez F.
Published: September 2006

Mononuclear unsymmetrical N‐heterocyclic carbene‐gold complexes and the corresponding solid catalysts in which a gold‐carbene complex has been immobilized on silica gel, ordered mesoporous silica (MCM‐41), and delaminated zeolite (ITQ‐2) have been prepared. These new catalysts have been tested in the hydrogenation of alkenes and the Suzuki cross‐coupling reaction to afford selectively non‐symmetrical biaryls. These reactions were studied with the soluble as well as with the heterogenized counterpart catalysts. The high accessibility introduced by the structure of the supports allows the preparation of highly efficient immobilized catalysts with TOFs up to 400 h−1. Moreover, the heterogenized complexes were reused and no deactivation of the catalysts can be observed.
Enzymatic Transformations 62. Preparative Scale Synthesis of Enantiopure Glycidyl Acetals using an Aspergillus niger Epoxide Hydrolase‐Catalysed Kinetic Resolution
Authors: Doumèche Bastien , Archelas Alain , Furstoss Roland
Published: September 2006

The hydrolytic kinetic resolution of five glycidaldehyde acetal derivatives was examined using the recombinant Aspergillus niger epoxide hydrolase as biocatalyst. This could successfully be performed, at room temperature, using solely demineralised water as solvent and following a two‐phase methodology allowing us to operate at a global substrate concentration as high as 200 g/L in the reactor. The observed E values were shown to be modest to excellent, depending on the structure of the acetal moiety, indicating that it is possible to achieve this resolution very efficiently just by choosing the right substituents. Both the unreacted (R)‐epoxide and the formed (S)‐diol could thus be obtained in good to excellent ee (ee>99 % for the epoxide). For the best substrates, the reaction could be performed within a few hours by using a biocatalyst over substrate molecular ratio of about 9 to 10×10−4 mol %. The turnover frequency (TOF) as well as the total turnover number (TON) of the enzyme proved to be excellent as compared to chemical catalysts – reaching respectively values in the order of 6×102 mol sub/mol enz/min and 6×104 mol sub/mol enz. The space‐time yield of the best (two‐phase) reactor could thus reach a value as high as 56 g/L/hour. As a demonstration experiment, a 50‐g scale resolution of glycidaldehyde 2,2‐dimethyltrimethylene acetal was performed.
Hydrophilic CNC‐Pincer Palladium Complexes: A Source for Highly Efficient, Recyclable Homogeneous Catalysts in Suzuki–Miyaura Cross‐Coupling
Authors: Churruca Fátima , SanMartin Raul , Inés Blanca , Tellitu Imanol , Domínguez Esther
Published: September 2006

The Suzuki biaryl coupling of a range of electronically dissimilar arylboronic acids and aryl bromides is performed in neat water with excellent to quantitative yields by means of a new CNC‐pincer palladium catalyst that is soluble in water due to its para‐carboxy group. Extremely high turnover numbers and frequencies combined with a remarkable robustness allow an effective catalyst reuse in sustainable conditions.
A 100 Gram‐Scale Production of a Key Building Block of Antibacterial Vancomycin: The Use of an Air‐Stable Chiral Zirconium Catalyst and Complete Recovery of a Silicon Source in Catalytic Asymmetric Mukaiyama Aldol Reaction
Authors: Isoda Takeshi , Akiyama Ryo , Oyamada Hidekazu , Kobayashi Shū
Published: September 2006

We have achieved a 100 gram‐scale production of anti‐(2S,3S)‐β‐(p‐benzyloxy‐m‐chloro)phenyl‐N‐trifluoroacetyl‐L‐serine methyl ester (1) in high yield with high diastereo‐ and enantioselectivities based on a catalytic asymmetric Mukaiyama aldol reaction. The use of an air‐stable zirconium‐molecular sieves combined catalyst [(R)‐I4‐ZrMS] facilitates easy manufacturing operation and reproducibility. Moreover, this is the first example of the complete recovery of the silicon source in a Mukaiyama aldol reaction.
Brønsted Acid‐Catalyzed Nucleophilic Substitution of Alcohols
Authors: Sanz Roberto , Martínez Alberto , Miguel Delia , Álvarez‐Gutiérrez Julia M. , Rodríguez Félix
Published: September 2006

Simple Brønsted acids such as p‐toluenesulfonic acid monohydrate (PTS) or polymer‐bound p‐toluenesulfonic acid efficiently catalyze the direct nucleophilic substitution of the hydroxy group of allylic and benzylic alcohols with a large variety of carbon‐ and heteroatom‐centered nucleophiles. Reaction conditions are mild, the process is conducted under an atmosphere of air without the need for dried solvents, and water is the only side product of the reaction.
Double Carbonylation Reactions of Enynols and Thiols to Form Thioester Substituted 6‐Membered Ring Lactones
Authors: Cao Hong , Xiao Wen‐Jing , Alper Howard
Published: September 2006

The double carbonylation reaction of enynols with thiols affords functionalized 6‐membered ring lactones. Two kinds of 6‐membered ring lactones were obtained by the use of different palladium complexes with added phosphine ligands.
Elejalde syndrome—A case report
Authors: Šilhánová Eva , Plevová Pavlína , Čuřík Romuald , Kasperčík Ivo , Křepelová Anna
Published: September 2006

Elejalde syndrome (McKusick 200995), also known as acrocephalopolydactylous dysplasia, is a rare condition. We describe a sixth patient with this syndrome which is characterized by craniosynostosis and hyperproliferation of fibroblasts in many tissues including skin, liver, kidney, and pancreas. The cause of the syndrome is the homozygous state of an autosomal recessive mutation. We present a hypothesis that Elejalde syndrome might be associated with an inactivating FGFR gene mutation. © 2006 Wiley‐Liss, Inc.
Festschrift for Dr. John M. Opitz: Pathogenesis of cardiac conduction disorders in children genetic and histopathologic aspects
Authors: Gilbert‐Barness Enid , Barness Lewis A.
Published: September 2006

Fetal dysrhythmias are usually transient. Abnormal fetal rates and rhythms during labor are “functional.” Fetal dysrhythmias may be associated with congenital heart disease and fetal hydrops. Bradycardia is usually related to fetal distress; supraventricular tachycardia, atrial flutter, and atrial fibrillation may be associated with severe congestive heart failure. Ventricular fibrillation is rare in the fetus and infant and is usually associated with myocardial necrosis with perimembranous septal defect; the nonbranching atrioventricular (AV) bundle may have an aberrant position and result in cardiac arrhythmia. Wolff–Parkinson–White syndrome with conduction abnormalities and left ventricular hypertrophy (LVH) is due to an accessory pathway that bypasses the AV sulcus and results in faster conduction. Carnitine deficiency may be primary or secondary and may result in cardiac arrhythmia. Histiocytoid cardiomyopathy is characterized by cardiomegaly, incessant ventricular tachycardia, and frequently sudden death. Arrhythmogenic right ventricular dysplasia (ARVD) results in ventricular tachycardia and left bundle branch block. Noncompaction of the left ventricle predisposes to potentially fatal arrhythmias. Long Q‐T syndromes (LQTS) are a heterogeneous group of disorders with many genetic mutations. Brugada syndrome is an autosomal dominant trait with right bundle branch block and ST elevation. Barth syndrome is an X‐linked disorder with dilated cardiomyopathy, cyclic neutropenia and skeletal myopathy. Hypertrophic cardiomyopathy in infancy may be related to metabolic diseases, particularly glycogen storage diseases; the familial form predisposes to sudden death. Arrhythmias following cardiac surgery may occur after closure of a ventricular septal defect (VSD) or damage to the conduction system. © 2006 Wiley‐Liss, Inc.
A fourth locus for hereditary hemorrhagic telangiectasia maps to chromosome 7
Authors: Bayrak‐Toydemir Pinar , McDonald Jamie , Akarsu Nurten , Toydemir Reha M. , Calderon Fernanda , Tuncali Timur , Tang Wei , Miller Franklin , Mao Rong
Published: September 2006

Hereditary hemorrhagic telangiectasia (HHT) is a genetically and clinically heterogeneous multisystem vascular dysplasia. Mutations of the endoglin and ACVRL1 genes are known to cause HHT. However, existence of HHT families in which linkage to these genes has been excluded has suggested that other gene(s) can cause HHT in some families. Recently, a family was reported to be linked to chromosome 5q, the HHT3 locus. Here we report on linkage results on a family with classic features of HHT, albeit a less severe phenotype with regards to epistaxis and telangiectases, in which linkage to HHT1, HHT2, and HHT3 is ruled out. Whole genome linkage analysis and fine mapping results suggested a 7 Mb region on the short arm of chromosome 7 (7p14) between STR markers D7S2252 and D7S510. We obtained a maximum two point LOD score of 3.60 with the STR marker D7S817. This region was further confirmed by haplotype analysis. These findings suggest the presence of another gene causing HHT (HHT4). The features in this family that strongly suggest the presence of a hereditary, multisystem vascular dysplasia would be easily missed during the typical evaluation and management of a patient with an AVM. This family helps emphasize the need to obtain a very detailed, targeted medical and family history for even mild, infrequent but recurring nosebleed, subtle telangiectases. Further studies of the candidate region and the identification of the gene responsible for the vascular anomalies in this family will add to our understanding of vascular morphogenesis and related disorders. © 2006 Wiley‐Liss, Inc.
Impaired visual search in drivers with Parkinson's disease
Authors: Uc Ergun Y. , Rizzo Matthew , Anderson Steven W. , Sparks JonDavid , Rodnitzky Robert L. , Dawson Jeffrey D.
Published: September 2006

Objective

To assess the ability for visual search and recognition of roadside targets and safety errors during a landmark and traffic sign identification task in drivers with Parkinson's disease (PD).

Methods

Seventy‐nine drivers with PD and 151neurologically normal older adults underwent a battery of visual, cognitive, and motor tests. The drivers were asked to report sightings of specific landmarks and traffic signs along a four‐lane commercial strip during an experimental drive in an instrumented vehicle.

Results

The drivers with PD identified significantly fewer landmarks and traffic signs, and they committed more at‐fault safety errors during the task than control subjects, even after adjusting for baseline errors. Within the PD group, the most important predictors of landmark and traffic sign identification rate were performances on Useful Field of View (visual speed of processing and attention) and Complex Figure Test‐Copy (visuospatial abilities). Trail Making Test (B‐A), a measure of cognitive flexibility independent of motor function, was the only independent predictor of at‐fault safety errors in drivers with PD.

Interpretation

The cognitive and visual deficits associated with PD resulted in impaired visual search while driving, and the increased cognitive load during this task worsened their driving safety. Ann Neurol 2006
A heterozygous effect for PINK1 mutations in Parkinson's disease?
Authors: Abou‐Sleiman Patrick M. , Muqit Miratul M. K. , McDonald Neil Q. , Yang Yan Xiang , Gandhi Sonia , Healy Daniel G. , Harvey Kirsten , Harvey Robert J. , Deas Emma , Bhatia Kailash , Quinn Niall , Lees Andrew , Latchman David S. , Wood Nicholas W.
Published: September 2006

Objective

To investigate the significance of PINK1 mutations in sporadic Parkinson's disease (PD).

Methods

We determined the frequency of PINK1 mutations by direct sequencing in a large series of PD patients with apparently sporadic disease (n = 768).

Results

Twelve heterozygous mutations were identified, nine in PD patients and three in control subjects.

Interpretation

Given the difficulty in interpreting the pathogenic significance of the heterozygous mutations that have already been reported in parkin and DJ‐1, we first determined the frequency of heterozygous PINK1 mutations in the general population by sequencing a large number of control subjects (n = 768), then subsequently assessed their functional significance by examining their effects on stress‐induced alterations to the mitochondrial membrane potential (ΔΨm). We demonstrate an enrichment of heterozygous mutations in sporadic PD patients compared with matched control subjects (1.2% in PD vs 0.4% in control subjects). Furthermore, we show that they adversely affect ΔΨm in a similar way to the familial G309D mutation. Although it remains difficult to conclusively demonstrate the pathogenicity of heterozygous mutations, the results of this study and the previously reported subclinical nigrostriatal dysfunction in carriers of heterozygous PINK1 mutations suggest the possibility that these heterozygous mutations are a significant risk factor in the development of later onset PD. Ann Neurol 2006
What does it mean to be an author? The intersection of credit, contribution, and collaboration in science
Authors: Birnholtz Jeremy P.
Published: September 2006

In this article, I draw on interview data gathered in the High Energy Physics (HEP) community to address recent problems stemming from collaborative research activity that stretches the boundaries of the traditional scientific authorship model. While authorship historically has been attributed to individuals and small groups, thereby making it relatively easy to tell who made major contributions to the work, recent collaborations have involved hundreds or thousands of individuals. Printing all of these names in the author list on articles can mean difficulties in discerning the nature or extent of individual contributions, which has significant implications for hiring and promotion procedures. This also can make collaborative research less attractive to scientists at the outset of a project. I discuss the issues that physicists are considering as they grapple with what it means to be “an author,” in addition to suggesting that future work in this area draw on the emerging economics literature on “mechanism design” in considering how credit can be attributed in ways that both ensure proper attribution and induce scientists to put forth their best effort.
Information arts and information science: Time to unite?
Authors: Karamuftuoglu Murat
Published: September 2006

This article explicates the common ground between two currently independent fields of inquiry, namely information arts and information science, and suggests a framework that could unite them as a single field of study. The article defines and clarifies the meaning of information art and presents an axiological framework that could be used to judge the value of works of information art. The axiological framework is applied to examples of works of information art to demonstrate its use. The article argues that both information arts and information science could be studied under a common framework; namely, the domain‐analytic or sociocognitive approach. It also is argued that the unification of the two fields could help enhance the meaning and scope of both information science and information arts and therefore be beneficial to both fields.
Article decay in the digital environment: An analysis of usage of OhioLINK by date of publication, employing deep log methods
Authors: Huntington Paul , Nicholas David , Jamali Hamid R. , Tenopir Carol
Published: September 2006

The article presents the early findings of an exploratory deep log analysis of journal usage on OhioLINK, conducted as part of the MaxData project, funded by the U.S. Institute of Museum and Library Services. OhioLINK, the original “Big Deal,” provides a single digital platform of nearly 6,000 full‐text journals for more than 600,000 people; for the purposes of the analysis, the raw logs were obtained from OhioLINK for the period June 2004 to December 2004. During this period approximately 1,215,000 items were viewed on campus in October 2004 and 1,894,000 items viewed off campus between June and December 2004. This article provides an analysis of the age of material that users consulted. From a methodological point of view OhioLINK offered an attractive platform to conduct age of publication usage studies because it is one of the oldest e‐journal libraries and thus offered a relatively long archive and stable platform to conduct the studies. The project sought to determine whether the subject, the search approach adopted, and the type of journal item viewed (contents page, abstract, full‐text article, etc.) was a factor in regard to the age of articles used.
Comparative citation analysis of duplicate or highly related publications
Authors: Knothe Gerhard
Published: September 2006

Four cases, illustrated by four examples, of duplicate or highly related publications can be distinguished and are analyzed here using citation data obtained from the Science Citation Index (SCI): (1) publication by different authors in the same journal; (2) the same author(s) publishing in different journals; (3) publication by different authors in different journals; (4) the same author(s) publishing highly related papers simultaneously in the same journal, often as part of a series of papers. Example 1, illustrating case 1, is an occurrence of highly related publications in mechanistic organic chemistry. Example 2, from analytical organic chemistry, contains elements of cases 2 and 3. Example 3, dealing solely with case 3, discusses two time‐delayed publications from analytical biochemistry, which were highlighted by Garfield several times in the past to show how the SCI could be utilized to avoid duplicate publication. Example 4, derived from synthetic organic chemistry (total syntheses of taxol), contains elements of cases 1, 3, and 4 and, to a lesser extent, case 2. The citation records of the highly related or duplicate publications can deviate considerably from the journal impact factors; this was observed in three of the four examples relating to cases 2, 3, and 4. The examples suggest that citation of a paper may depend significantly on the journal in which it is published. As an indicator of this dependence, the journals in which the papers used in the present examples appeared were examined. Other factors such as key words in the paper title may also play a role.
Measuring online information seeking context, Part 1: Background and method
Authors: Kelly Diane
Published: September 2006

Context is one of the most important concepts in information seeking and retrieval research. However, the challenges of studying context are great; thus, it is more common for researchers to use context as a post hoc explanatory factor, rather than as a concept that drives inquiry. The purposes of this study were to develop a method for collecting data about information seeking context in natural online environments, and identify which aspects of context should be considered when studying online information seeking. The study is reported in two parts. In this, the first part, the background and method are presented. Results and implications of this research are presented in Part 2 (Kelly, in press). Part 1 discusses previous literature on information seeking context and behavior and situates the current work within this literature. This part further describes the naturalistic, longitudinal research design that was used to examine and measure the online information seeking contexts of users during a 14‐week period. In this design, information seeking context was characterized by a user's self‐identified tasks and topics, and several attributes of these, such as the length of time the user expected to work on a task and the user's familiarity with a topic. At weekly intervals, users evaluated the usefulness of the documents that they viewed, and classified these documents according to their tasks and topics. At the end of the study, users provided feedback about the study method.
A New Protein Engineering Approach Combining Chemistry and Biology, Part I; Site‐Specific Incorporation of 4‐Iodo‐L‐phenylalanine in vitro by Using Misacylated Suppressor tRNAPhe
Authors: Kodama Koichiro , Fukuzawa Seketsu , Sakamoto Kensaku , Nakayama Hiroshi , Kigawa Takanori , Yabuki Takashi , Matsuda Natsuko , Shirouzu Mikako , Takio Koji , Tachibana Kazuo , Yokoyama Shigeyuki
Published: September 2006

An Escherichia coli suppressor tRNAPhe (tRNAPheCUA) was misacylated with 4‐iodo‐L‐phenylalanine by using the A294G phenylalanyl–tRNA synthetase mutant (G294‐PheRS) from E. coli at a high magnesium‐ion concentration. The preacylated tRNA was added to an E. coli cell‐free system and a Ras protein that contained the 4‐iodo‐L‐phenylalanine residue at a specific target position was synthesized. Site‐specific incorporation of 4‐iodo‐L‐phenylalanine was confirmed by using LC–MS/MS. Free tRNAPheCUA was not aminoacylated by aminoacyl–tRNA synthetases (aaRSs) present in the E. coli cell‐free system. Our approach will find wide application in protein engineering since an aryl iodide tag on proteins can be used for site‐specific functionalization of proteins.
Sequence‐Dependent Binding of Dipeptides by an Artificial Receptor in Water
Authors: Schmuck Carsten , Rupprecht Daniel , Wienand Wolfgang
Published: September 2006

An artificial dipeptide receptor (1) was designed and observed to bind the deprotonated dipeptide Ac‐D‐Ala‐D‐Ala‐OH in buffered water with K = 33 100 m−1, whereas other dipeptides such as Ac‐Gly‐Gly‐OH or Ac‐D‐Val‐D‐Val‐OH were bound less efficiently, by factors of more than 10 (K < 3000 m−1). The efficient binding and the pronounced sequence selectivity are the result of a combination of strong electrostatic contacts and size‐discriminating hydrophobic interactions. To provide such a combination, a guanidiniocarbonylpyrrole cation was attached to a novel cyclotribenzylene‐substituted alanine derivative 5, to provide a hydrophobic bowl‐shaped cavity just large enough to bind a methyl group but not any larger alkyl chains, thus causing the receptor to prefer alanine to valine. We describe the synthesis of 1 and the evaluation of its complexation properties in UV and fluorescence titration studies.
DyNAs: Constitutional Dynamic Nucleic Acid Analogues
Authors: Sreenivasachary Nampally , Hickman David T. , Sarazin Dominique , Lehn Jean‐Marie
Published: September 2006

Dynamic cationic polymers were generated in aqueous media from functionally complementary monomers bearing nucleobase groups.1H NMR spectroscopy was used to follow the polycondensation reaction of the nucleobase‐appended dihydrazides1and2with the dialdehydesBandC. The reversibility of these polymers was established by proton NMR spectroscopy through exchange of the dihydrazide2with polymer1 B. The polymers1 B,2 B,1 C, and2 Crepresent dynamic biopolymers of nucleic acid type, DyNAs. Electrostatic interaction of these polymers with polyanionic entities, such as polyphosphates, polynucleotides, and polyaspartic acid, was shown to take place. It induces a change in size of the dynamic polymer, as it responds by an increase in degree of polymerization to an increase of the overall anionic charge introduced, that is, to the total electrostatic interaction.
δ‐La(BO2)3 ( δ‐LaB3O6): A New High‐Pressure Modification of Lanthanum meta‐Oxoborate.
Authors: Heymann Gunter , Soltner Theresa , Huppertz Hubert
Published: September 2006

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, please click on HTML or PDF.
Resonance in the Electron‐Doped High‐Transition‐Temperature Superconductor Pr0.88LaCe0.12CuO4‐δ.
Authors: Wilson Stephen D. , Dai Pengcheng , Li Shiliang , Chi Songxue , Kang H. J. , Lynn J. W.
Published: September 2006

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, please click on HTML or PDF.
Electrical and Magnetic Properties of NdCuPb Compound
Authors: Oener Yildirhan
Published: September 2006

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, please click on HTML or PDF.
Enthalphies of Formation for the Al—Cu—Ni—Zr Quaternary Alloys Calculated via a Combined Approach of Geometric Model and Miedema Theory.
Authors: Ouyang Yifang , Zhong Xiaping , Du Yong , Feng Yuanping , He Yuehui
Published: September 2006

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, please click on HTML or PDF.
Cheap and Environmentally Benign Electrochemical Energy Storage and Conversion Devices Based on AlI3 Electrolytes.
Authors: Xue Bofei , Fu Zhengwen , Li Hong , Liu Xizhe , Cheng Sunchao , Yao Jia , Li Dongmei , Chen Liquan , Meng Qingbo
Published: September 2006

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, please click on HTML or PDF.
A Computational Investigation on the Electrochemical Properties of Spinel‐Like LiCoAsO4 as Positive Electrode for Lithium‐Ion Batteries.
Authors: Arroyo‐de Dompablo M. Elena , Amador Ulises
Published: September 2006

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, please click on HTML or PDF.
Ca7Co8Sn25 — Ca3Co4Sn13 Revised.
Authors: Schreyer Martin , Faessler Thomas F.
Published: September 2006

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, please click on HTML or PDF.
α,β‐Unsaturated β‐Silyl Imide Substrates for Catalytic, Enantioselective Conjugate Additions: A Total Synthesis of (+)‐Lactacystin and the Discovery of a New Proteasome Inhibitor.
Authors: Balskus Emily P. , Jacobsen Eric N.
Published: September 2006

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, please click on HTML or PDF.
Highly Enantioselective Aza‐Baylis—Hillman Reaction in a Chiral Reaction Medium.
Authors: Gausepohl Rolf , Buskens Pascal , Kleinen Jochen , Bruckmann Angelika , Lehmann Christian W. , Klankermayer Juergen , Leitner Walter
Published: September 2006

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, please click on HTML or PDF.
Enantioselective Hydrogenation of Acyclic Aromatic N‐Aryl Imines Catalyzed by an Iridium Complex of (S,S)‐1,2‐Bis(tert‐butylmethylphosphino)ethane.
Authors: Imamoto Tsuneo , Iwadate Noriyuki , Yoshida Kazuhiro
Published: September 2006

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, please click on HTML or PDF.
Reaction Behavior of Cumulene in Diels—Alder and Friedel—Crafts Reactions.
Authors: Asakawa Tomohiro , Iinuma Mie , Furuta Takumi , Fujii Satoshi , Kan Toshiyuki , Tanaka Kiyoshi
Published: September 2006

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, please click on HTML or PDF.
Unusual Ambiphilic Carbenoid Equivalent in Amide Cyclopropanation.
Authors: Lin Kuo‐Wei , Yan Shiuan , Hsieh I‐Lin , Yan Tu‐Hsin
Published: September 2006

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, please click on HTML or PDF.
Urea‐Hydrogen Peroxide and Microwave: An Eco‐Friendly Blend for Allylic Oxidation of Alkenes with Catalytic Selenium Dioxide.
Authors: Manktala R. , Dhillon R. S. , Chhabra B. R.
Published: September 2006

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, please click on HTML or PDF.
Iodination of Alcohols Using Triphenylphosphine/Iodine under Solvent‐Free Conditions Using Microwave Irradiation.
Authors: Hajipour Abdol Reza , Falahati Ali Reza , Ruoho Arnold E.
Published: September 2006

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, please click on HTML or PDF.
Highly Regioselective Ring Opening of Epoxides and Aziridines Using (Bromodimethyl)sulfonium Bromide.
Authors: Das Biswanath , Krishnaiah Maddeboina , Venkateswarlu Katta
Published: September 2006

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, please click on HTML or PDF.
Reaction of Azolethiones with Diacetylene.
Authors: Volkov A. N. , Vokova K. A.
Published: September 2006

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, please click on HTML or PDF.
Basic Ionic Liquid as Catalysis and Reaction Medium: A Novel and Green Protocol for the Markovnikov Addition of N‐Heterocycles to Vinyl Esters, Using a Task‐Specific Ionic Liquid, [bmIm]OH.
Authors: Xu Jian‐Ming , Liu Bo‐Kai , Wu Wei‐Bo , Qian Chao , Wu Qi , Lin Xian‐Fu
Published: September 2006

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, please click on HTML or PDF.
Highly Enantioselective Access to Primary Propargylamines: 4‐Piperidinone as a Convenient Protecting Group.
Authors: Aschwanden Patrick , Stephenson Corey R. J. , Carreira Erick M.
Published: September 2006

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, please click on HTML or PDF.
Microwave Assisted Fast and Clean Conversion of Mesylate to Azide: Synthesis of (1S,2R/1R,2S)‐1‐Azido‐2‐carbocyclic Amines as Immediate Precursors to Versatile 1,2‐cis‐Diamines.
Authors: Govindaraju T.
Published: September 2006

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, please click on HTML or PDF.
Microwave‐Assisted Suzuki Coupling Reactions with an Encapsulated Palladium Catalyst for Batch and Continuous‐Flow Transformations.
Authors: Baxendale Ian R. , Griffiths‐Jones Charlotte M. , Ley Steven V. , Tranmer Geoffrey K.
Published: September 2006

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, please click on HTML or PDF.
Photomediated Synthesis of β‐Alkylketones from Cycloalkanes.
Authors: Dondi Daniele , Cardarelli Anna Maria , Fagnoni Maurizio , Albini Angelo
Published: September 2006

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, please click on HTML or PDF.
Mix‐and‐Heat Benzylation of Alcohols Using a Bench‐Stable Pyridinium Salt.
Authors: Poon Kevin W. C. , Dudley Gregory B.
Published: September 2006

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, please click on HTML or PDF.
Regeneration of Carbonyl Compounds from Oximes, Semicarbazones and Tosylhydrazones with Calcium Hypochlorite and Moist Montmorillonite K‐10.
Authors: Movassagh Barahman , Dahaghin Ebrahim
Published: September 2006

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, please click on HTML or PDF.
Protection of Aldehydes as 1,1‐Diacetates and Deprotection of 1,1‐Diacetates to Aldehydes.
Authors: Nanda Puja , Paul Satya , Gupta Rajive
Published: September 2006

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, please click on HTML or PDF.
Acyl Iodides in Organic Synthesis. Part 7. Reactions with Trialkyl(alkynyl)silanes, ‐germanes, and ‐stannanes.
Authors: Voronkov M. G. , Trukhina A. A. , Vlasova N. N. , Mirskov R. G. , Yarosh O. G.
Published: September 2006

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, please click on HTML or PDF.
Copper(I) Chloride Catalyzed Three‐Component Coupling Reaction of Primary Amines with Electrophiles and α‐Halogen‐Substituted Allylsilanes to Form Unsymmetrical Tertiary Amines.
Authors: Kozuka Makoto , Inoue Akihiko , Tsuchida Teruko , Mitani Michiharu
Published: September 2006

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, please click on HTML or PDF.
A Tripodal Sulfur Ligand for the Selective Ruthenium‐Catalyzed Hydrogenation of Dimethyl Oxalate.
Authors: Boardman Brian , Hanton Martin J. , van Rensburg Hendrik , Tooze Robert P.
Published: September 2006

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, please click on HTML or PDF.
Diastereoselective and Enantiospecific Synthesis of γ‐Substituted α,β‐Unsaturated Nitriles from O‐Protected Allylic Cyanohydrins.
Authors: Baeza Alejandro , Casas Jesus , Najera Carmen , Sansano Jose M.
Published: September 2006

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, please click on HTML or PDF.
Synthesis of Pentalene Systems Employing a Sequence of Pauson—Khand Reaction, Michael Reaction, and Desilylation.
Authors: Becheanu Armand , Bell Thomas , Laschat Sabine , Baro Angelika , Frey Wolfgang , Steinke Nelli , Fischer Peter
Published: September 2006

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, please click on HTML or PDF.
Unexpected Multicomponent Reaction of 2/4‐Methoxyarylaldehydes with Arylhydroxylamines and Maleic Anhydride: A Novel Synthesis of Unsymmetrical Diarylamines.
Authors: Sridharan V. , Karthikeyan K. , Muthusubramanian S.
Published: September 2006

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, please click on HTML or PDF.
(IPr)Pd(acac)Cl: An Easily Synthesized, Efficient, and Versatile Precatalyst for C—N and C—C Bond Formation.
Authors: Marion Nicolas , Ecarnot Elise C. , Navarro Oscar , Amoroso Dino , Bell Andrew , Nolan Steven P.
Published: September 2006

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, please click on HTML or PDF.
Chiral Borate Esters in Asymmetric Synthesis. Part 5. Asymmetric Reduction of Oxime Ethers Promoted by Chiral Spiroborate Esters with an O3BN Framework.
Authors: Chu Yunbo , Shan Zixing , Liu Dejun , Sun Nannan
Published: September 2006

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, please click on HTML or PDF.
Synthesis and Characterization of New Triazenide Salts
Authors: Virag Andrej , Meden Anton , Kocevar Marijan , Polanc Slovenko
Published: September 2006

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, please click on HTML or PDF.
Ir‐ and Ru‐Catalyzed Sequential Reactions: Asymmetric α‐Alkylative Reduction of Ketones with Alcohols
Authors: Onodera Gen , Nishibayashi Yoshiaki , Uemura Sakae
Published: September 2006

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, please click on HTML or PDF.
Synthesis of β‐Amino Alcohols from Aromatic Amines and Alkylene Carbonates Using Na‐Y Zeolite Catalyst.
Authors: Shivarkar Anandkumar B. , Gupte Sunil P. , Chaudhari Raghunath V.
Published: September 2006

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, please click on HTML or PDF.
Synthons for Biologically Active Compounds on the Basis of Naphthalene Ozonolysis Products.
Authors: Kukovinets O. S. , Kislitsyn M. I. , Zainullin R. A. , Abdullin M. I. , Galin F. Z.
Published: September 2006

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, please click on HTML or PDF.
Selective Terminal Heck Arylation of Vinyl Ethers with Aryl Chlorides: A Combined Experimental—Computational Approach Including Synthesis of Betaxolol.
Authors: Datta Gopal K. , von Schenck Henrik , Hallberg Anders , Larhed Mats
Published: September 2006

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, please click on HTML or PDF.
Halogenation of N‐Substituted p‐Quinone Imines and p‐Quinone Oximes Esters. Part 4. Chlorination and Bromination of N‐Arylsulfonyl‐2(3)‐methyl(2‐chloro)‐1,4‐benzoquinone Monoimines.
Authors: Avdeenko A. P. , Konovalova S. A.
Published: September 2006

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, please click on HTML or PDF.
A Simple and Environmentally Friendly Method for the Synthesis of N‐Phenylanthranilic Acid Derivatives.
Authors: Girisha Hanakere R. , Srinivasa Gejjalagere R. , Gowda D. Channe
Published: September 2006

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, please click on HTML or PDF.
Synthesis of γ‐N‐Acylamino‐β‐keto Esters and Ethyl 5‐Oxazoleacetates via Ritter Reaction and Hydration of γ‐Hydroxy‐α,β‐alkynoic Esters.
Authors: Rao K. Srinivasa , Reddy D. Srinivasa , Pal Manojit , Mukkanti K. , Iqbal Javed
Published: September 2006

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, please click on HTML or PDF.
Construction of Enantiomerically Enriched Tertiary α‐Hydroxycarboxylic Acid Derivatives by Phase‐Transfer‐Catalyzed Asymmetric Alkylation of Diaryloxazolidin‐2,4‐diones.
Authors: Ooi Takashi , Fukumoto Kazuhiro , Maruoka Keiji
Published: September 2006

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, please click on HTML or PDF.
Chemo‐ and Stereoselectivity of the Reaction of Aromatic Aldehydes with Triphenylphosphine and Trichloroacetic Acid Derivatives.
Authors: Matveeva E. D. , Erin A. S. , Osetrov A. G. , Leshcheva I. F. , Kurts A. L.
Published: September 2006

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, please click on HTML or PDF.
A Highly Enantioselective, Pd—TangPhos‐Catalyzed Hydrogenation of N‐Tosylimines.
Authors: Yang Qin , Shang Gao , Gao Wenzhong , Deng Jingen , Zhang Xumu
Published: September 2006

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, please click on HTML or PDF.
Oxidation of Prochiral Sulfides with Chiral Dioxirane.
Authors: Dieva S. A. , Eliseenkova R. M. , Efremov Yu. Ya. , Sharafutdinova D. R. , Bredikhin A. A.
Published: September 2006

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, please click on HTML or PDF.