bluuebunny/crossref_metadata_2025 huggingface dataset:
Untersuchungen über Schiffsche Basen, V. Massenspektrometrische Untersuchungen an doppelten Aldiminen von 1.2‐Diamino‐cyclopropanen und ihren Valenzisomerisierungsprodukten
Authors: Staab Heinz A. , Wünsche Christian
Published: June 2007

Die massenspektrometrische Fragmentierung von 2.3‐Dihydro‐1.4‐diazepinen wurde untersucht. Auf Grund der Massenspektren wurde für die Valenzisomerisierungsprodukte doppelter Aldimine von 1.2‐Diamino‐cyclopropanen die 2.3‐Dihydro‐1.4‐diazepin‐Struktur bewiesen.
Benzazole, XIX. Glykoside des Benzthiazolthions
Authors: Zinner Helmut , Peseke Klaus
Published: June 2007

Bei der Reaktion von α‐Acetobromhexosen mit Benzthiazolthion‐yl‐natrium in Äthanol werden nur S‐[Tetraacetyl‐β‐glykosyl]‐benzthiazolthione gebildet. Diese Verbindungen erhält man auch durch Umsetzen von α‐Acetobromhexosen mit Bis‐[benzthiazolthion‐yl]‐quecksilber in Dimethylformamid; als Nebenprodukte treten hier kleine Mengen an N‐[Tetraacetyl‐glykosyl]‐benzthiazolthionen auf. Die genannten Tetraacetate lassen sich zu freien S‐ bzw. N‐[Glykosyl]‐benzthiazolthionen entacetylieren. Die Strukturen der Verbindungen gehen aus den UV‐Absorptionsspektren hervor.
Über heterocyclische Siebenringsysteme, XIV. Weitere Ringschlußreaktionen mit o.o′‐Diamino‐biphenyl
Authors: Ried Walter , Sinharay Akhileswar
Published: June 2007

o.o′‐Diamino‐biphenyl reagiert mit aromatischen, heterocyclischen und α‐elektronegativ substituierten aliphatischen Imidsäureester‐hydrochloriden zu 6‐substituierten 5H‐Dibenzo[d.f][1.3]diazepinen (1–17). Mandelimidsäureester‐ und die kernsubstituierten Mandelimidsäureester‐hydrochloride setzen sich zu 6‐[α‐Hydroxy‐benzyl]‐5 H‐dibenzo[d.f][1.3]diazepinen um, die leicht zu den 6‐Benzoyl‐Derivaten dehydriert werden.
Zur Hydrolyse amphoterer Metallalkoxide, VII. Die Verseifung des Orthovanadinsäure‐tert.‐butylesters in Gegenwart von Kupfersalzen
Authors: Fuchs Joachim , Jahr Karl Friedrich , Eberhard Arnold , Preuss Fritz
Published: June 2007

Bei der Hydrolyse des Orthovanadinsäure‐tert.‐butylesters in Gegenwart von in organischen Solventien gelösten Kupfersalzen werden Kupferpolyvanadate erhalten. Das Verhältnis CuO:V2O5 (Base/Säure‐Verhältnis) der entstehenden Salze wird durch das Anion des eingesetzten Kupfersalzes sowie durch die Art des Lösungsmittels bestimmt. Dargestellt wurden die Verbindungen Cu3V10O28, Cu2H2V10O28 und CuV6O16.
Über die Umsetzung von Bromdiacetyl sowie alicyclischen 1‐Chlor‐dionen‐(2.3) mit primären und sekundären Aminen zu Reduktonen und einige Eigenschaften der Produkte
Authors: Simon Helmut , Heubach Günther , Bitterlich Wolfgang , Gleinig Harald
Published: June 2007

Aus verschiedenen Halogendiketonen wurden mit primären und sekundären Aminen aci‐Reduktone dargestellt. Die aus sekundären Aminen erhaltenen Verbindungen sind gleich oder analog solchen, die bei der Einwirkung von Salzen sekundärer Amine auf Zucker erhalten werden. Insbesondere die aus Bromdiacetyl gewonnenen Produkte wurden in ihrer Struktur sowie in ihrem Verhalten bei der Hydrolyse und Hydrierung näher untersucht.
Über Schwefel‐Ylide, IX. Reaktionen des Dimethyl‐oxo‐sulfoniummethylids mit Azomethinen, Azinen, Hydrazonen und Nitrilen
Authors: König Horst , Metzger Horst , Seelert Kurt
Published: June 2007

Dimethyl‐oxo‐sulfoniummethylid (1) bildet mit ungesättigten Stickstoff‐Kohlenstoff‐Systemen Aziridine, methylierte oder schwefelhaltige Produkte, die Einblick in die Reaktionsmechanismen erlauben. OH‐ und NH‐acide Verbindungen werden methyliert.
Zur Einwirkung von Alkali auf Benzthiazolium‐ und Thiazoliumsalze
Authors: Friedrich Walter , Kehr Helmut , Kröhnke Fritz , Schiller Peter
Published: June 2007

Die aus N‐Phenacyl‐benzthiazoliumbromiden (1) mit Alkali in wasserfreiem Medium erhaltenen Anhydrobasen erweisen sich als Dimere, als Bi‐benzthiazolinylidene‐(2.2′). Thermisch entsteht aus ihnen Bi‐benzthiazolyl‐(2.2′). — Die für (Benz‐)Thiazoliumsalze charakteristische leichte Ringaufspaltung mit wäßrigem Alkali zeigt sich auch am N‐[p‐Nitro‐benzyl]‐benzthiazoliumbromid (7); auch aus ihm läßt sich ein Dimeres mit Äthylenstruktur gewinnen. Mit Triäthylamin erhält man ein Ylid. Daß unter geeigneten Umständen aus 7 ein Nitron entstehen kann, beweist gleichwohl eine gewisse N‐Methylen‐Aktivität. Diese ist deutlich ausgeprägter in N‐Phenacyl‐ und N‐[p‐Nitro‐phenacyl]‐thiazolium‐ und ‐4‐methyl‐thiazoliumsalzen, obwohl man auch aus ihnen 2.2′‐Dimere erhalten kann.
Au34‐: A Chiral Gold Cluster?
Authors: Lechtken Anne , Schooss Detlef , Stairs Jason R. , Blom Martine N. , Furche Filipp , Morgner Nina , Kostko Oleg , von Issendorff Bernd , Kappes Manfred M.
Published: June 2007

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.
Structure and Magnetic Properties of Lanthanum and Calcium‐Deficient La0.5Ca0.5MnO3 Manganites.
Authors: Walha I. , Ehrenberg H. , Fuess H. , Cheikhrouhou A.
Published: June 2007

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.
Solvothermal Synthesis, Crystal Structure, and Thermal Stability of Three‐Layered Thioantimonate(III) Complexes: [Ni(C3H10N2)3] Sb4S7, [C4H14N2] Sb8S13×H2O, and [C6H18N2] Sb10S16×H2O.
Authors: Zhang Meng , Sheng Tian Lu , Huang Xi He , Fu Rui Biao , Wang Xin , Hu Sheng Min , Xiang Sheng Chang , Wu Xin Tao
Published: June 2007

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.
New Synthesis of 2‐Polyfluoroalkyl Substituted 1,4,5,6‐Tetrahydropyrimidines and 4,5,6,7‐Tetrahydro‐1H‐1,3‐diazepines.
Authors: Rudnichenko Alexander V. , Shermolovich Yuriy G.
Published: June 2007

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.
Dioxane Dibromide‐Mediated Solvent‐Free Synthesis of Vicinal Dibromides.
Authors: Chaudhuri Subrata Kumar , Roy Sanchita , Saha Manabendra , Bhar Sanjay
Published: June 2007

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.
Gold(I)‐Catalyzed Enantioselective Intramolecular Hydroamination of Allenes.
Authors: LaLonde Rebecca L. , Sherry Benjamin D. , Kang Eun Joo , Toste F. Dean
Published: June 2007

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.
Poly(pyrazol‐1‐ylmethyl)benzene Palladium Complexes: Synthesis, Characterization and Evaluation as Heck Coupling Catalysts.
Authors: Motsoane Nthabiseng M. , Guzei Ilia A. , Darkwa James
Published: June 2007

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 Novel Application of Tin‐Based Alkoxide Anion for Deacetylation.
Authors: Lin Weiying , Long Lingliang , Peng Daiwei , Guo Cancheng
Published: June 2007

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.
Hydrogenation of Imino‐bisnitriles — Synthesis of Novel Triamines.
Authors: Sundaramoorthi Raji , Keenan Terence P.
Published: June 2007

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.
Nonenzymatic Enantioselective Monoacetylation of Prochiral 2‐Protected Amino‐2‐alkyl‐1,3‐propanediols Utilizing a Chiral Sulfonamide—Zn Complex Catalyst.
Authors: Honjo Takashi , Nakao Michiyasu , Sano Shigeki , Shiro Motoo , Yamaguchi Kentaro , Sei Yoshihisa , Nagao Yoshimitsu
Published: June 2007

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 Way to Highly Enantiomerically Enriched Aza‐Morita—Baylis—Hillman‐Type Products.
Authors: Utsumi Naoto , Zhang Haile , Tanaka Fujie , Barbas Carlos F. III
Published: June 2007

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.
Ring Opening of Chiral 2‐(1‐Aminoalkyl)epoxides by Aliphatic Thiols with Total Selectivity: Synthesis of Enantiopure 3‐Amino‐1‐(alkylthio)alkan‐2‐ols.
Authors: Concellon Jose M. , del Solar Virginia , Suarez Jose Ramon , Blanco Elena G.
Published: June 2007

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.
Readily Accessible 9‐epi‐Amino Cinchona Alkaloid Derivatives Promote Efficient, Highly Enantioselective Additions of Aldehydes and Ketones to Nitroolefins.
Authors: McCooey Seamus H. , Connon Stephen J.
Published: June 2007

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.
Asymmetric Mannich Reactions with in situ Generation of Carbamate‐Promoted Imines by an Organic Catalyst.
Authors: Song Jun , Shih Hui‐Wen , Deng Li
Published: June 2007

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 Efficient Catalyst for Suzuki Coupling of Aryl Halides and Bromoarylphosphine Oxides.
Authors: Joshaghani Mohammad , Daryanavard Marzieh , Rafiee Ezzat , Xiao Jianliang , Baillie Collin
Published: June 2007

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.
Broensted Acid Catalyzed Propargylation of 1,3‐Dicarbonyl Derivatives. Synthesis of Tetrasubstituted Furans.
Authors: Sanz Roberto , Miguel Delia , Martinez Alberto , Alvarez‐Gutierrez Julia M. , Rodriguez Felix
Published: June 2007

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 Epoxidation of Conjugated Z‐Olefins with Newly Modified Mn(salen) Complex.
Authors: Egami Hiromichi , Irie Ryo , Sakai Ken , Katsuki Tsutomu
Published: June 2007

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 Addition of Chlorotitanium Enolates of N‐Acyl Thiazolidinethione to Activated Imines — A Novel Synthesis of β‐Lactams.
Authors: Herold‐Dublin Marike , Liotta Dennis C.
Published: June 2007

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.
Metal‐Free Entry to Phosphonylated Isoindoles by a Cascade of 5‐exo‐dig Cyclization, a [1,3]‐Alkyl Shift, and Aromatization under Microwave Heating.
Authors: Dieltiens Nicolai , Stevens Christian V.
Published: June 2007

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.
Gold(III)‐Catalyzed Double Hydroamination of o‐Alkynylaniline with Terminal Alkynes Leading to N‐Vinylindoles.
Authors: Zhang Yuhua , Donahue James P. , Li Chao‐Jun
Published: June 2007

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.
CeCl3×7H2O/IBX‐Promoted Oxidation of 3‐Alkylindoles to 3‐Hydroxyoxindoles.
Authors: Yadav J. S. , Reddy B. V. Subba , Reddy Ch. Suresh , Krishna A. D.
Published: June 2007

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.
Carbazole Synthesis by Platinum‐Catalyzed C—H Functionalizing Reaction Using Water as Reoxidizing Reagent.
Authors: Yamamoto Mitsuru , Matsubara Seijiro
Published: June 2007

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.
1,3‐Dipolar Cycloaddition of Ethyl Diazoacetate to Alkynes in the Pores of Zeolite NaY.
Authors: Kobayashi Keijiro , Igura Yuta , Imachi Shouhei , Masui Yoichi , Onaka Makoto
Published: June 2007

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.
Novel Procedure for Highly Stereoselective Synthesis of Bicyclic Cyclopropane‐lactam with cis‐2‐Aryl‐1‐benzoyl‐3,3‐dicyanocyclopropane and 2‐Cyanomethyl‐1,3‐benzothiazole in Water.
Authors: Ren Zhongjiao , Cao Weiguo , Chen Jie , Lu Yeying
Published: June 2007

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.
4‐Hydroxy‐2‐quinolones. Part 109. Alkylation of 4‐Substituted Ethyl 2‐Oxo‐1,2‐dihydroquinoline‐3‐carboxylates.
Authors: Ukrainets I. V. , Sidorenko L. V. , Gorokhova O. V. , Bereznyakova N. L. , Shishkina S. V.
Published: June 2007

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.
4‐Hydroxy‐2‐quinolones. Part 110. Bromination of 1‐R‐4‐Hydroxy‐2‐oxo‐1,2‐dihydroquinoline‐3‐carboxylic Acid Anilides.
Authors: Ukrainets I. V. , Tkach A. A. , Sidorenko L. V. , Gorokhova O. V.
Published: June 2007

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.
Investigation on 2,3′‐Biquinolyl Series. Part 21. Reactions of 1′‐Alkyl‐4′‐aryl‐1′,4′‐dihydro‐2,3′‐biquinolyls and 1′‐Alkyl‐2′‐aryl‐1′,2′‐dihydro‐2,3′‐biquinolyls with Sulfur.
Authors: Moiseev D. V. , Goncharov V. I. , Aksenov A. V.
Published: June 2007

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.
Formation of the Pyridine Ring in the Synthesis of Dipyrido[3′,2′:4,5]thieno[3,2‐b:3,2‐d]pyridines.
Authors: Vasilin V. K. , Lipunov M. M. , Konyushkin L. D. , Kaigorodova E. A. , Krapivin G. D.
Published: June 2007

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.
Rapid Access to Pyrimido[5,4‐c]isoquinolines via a Sulfur Monoxide Extrusion Reaction.
Authors: Fu Renzhong , Xu Xianxiu , Dang Qun , Chen Feng , Bai Xu
Published: June 2007

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.
Regioselective Two‐Step Synthesis of 3‐Substituted 2‐Aminoimidazo[1,2‐a]pyrimidines.
Authors: Carballares Santiago , Cifuentes Marta M. , Stephenson Gregory A.
Published: June 2007

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.
Electrophilic Aromatic Substitution Reactions of 1,2‐Dihydro‐1,2‐azaborines.
Authors: Pan Jun , Kampf Jeff W. , Ashe Arthur J. III
Published: June 2007

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.
Convenient and Regioselective One‐Pot Solvent‐Free Synthesis of β‐Hydroxyphosphonates.
Authors: Sardarian A. R. , Shahsavari‐Fard Z.
Published: June 2007

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 the First Representatives of Benzanellated Dihydroselenochromenes.
Authors: Drevko Ya. B. , Fedotova O. V.
Published: June 2007

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.
Coumarin Base‐Pair Replacement as a Fluorescent Probe of Ultrafast DNA Dynamics.
Authors: Coleman Robert S. , Berg Mark A. , Murphy Catherine J.
Published: June 2007

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 Perylenedicarboxamide Linker for DNA Hairpins.
Authors: Lewis Frederick D. , Zhang Ligang , Kelley Richard F. , McCamant David , Wasielewski Michael R.
Published: June 2007

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.
Naphthalenyl‐ and Anthracenyl‐Ethynyl dT Analogues as Base Discriminating Fluorescent Nucleosides and Intramolecular Energy Transfer Donors in Oligonucleotide Probes.
Authors: Xiao Qiang , Ranasinghe Rohan T. , Tang Adrian M. P. , Brown Tom
Published: June 2007

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.
Furan Decorated Nucleoside Analogues as Fluorescent Probes: Synthesis, Photophysical Evaluation, and Site‐Specific Incorporation.
Authors: Greco Nicholas J. , Tor Yitzhak
Published: June 2007

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.
Use of 2‐Aminopurine as a Fluorescent Tool for Characterizing Antibiotic Recognition of the Bacterial rRNA A‐Site.
Authors: Barbieri Christopher M. , Kaul Malvika , Pilch Daniel S.
Published: June 2007

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.
Monitoring G‐Quadruplex Structures and G‐Quadruplex—Ligand Complex Using 2‐Aminopurine Modified Oligonucleotides.
Authors: Kimura Takumi , Kawai Kiyohiko , Fujitsuka Mamoru , Majima Tetsuro
Published: June 2007

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 Novel Polyhydroxylated Tetrahydropyranopyrroles.
Authors: Naud Sebastien , Pipelier Muriel , Chaumette Christophe , Viault Guillaume , Huet Francois , Legoupy Stephanie , Dubreuil Didier
Published: June 2007

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.
Expedient Stereoselective Synthesis of Coronafacic Acid Through Intramolecular Diels—Alder Cyclization.
Authors: Moreau Benoit , Ginisty Maryon , Alberico Dino , Charette Andre B.
Published: June 2007

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.
Crystalline Oxyfluorinated Open‐Framework Compounds: Silicates, Metal Phosphates, Metal Fluorides and Metal‐Organic Frameworks (MOF)
Authors: Loiseau Thierry , Ferey Gerard
Published: June 2007

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.
Thermal Dehydration Characteristics of Hydrated Salts: A Critical Review
Authors: Kanungo S. B. , Mishra S. K.
Published: June 2007

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.
Characterization of Coordination Compounds by Electrochemical Parameters
Authors: Pombeiro Armando J. L.
Published: June 2007

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.
Supramolecular Chirality in Coordination Chemistry
Authors: Seeber Georg , Tiedemann Bryan E. F. , Raymond Kenneth N.
Published: June 2007

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 Review of Antiinfective and Antiinflammatory Chalcones
Authors: Nowakowska Zdzislawa
Published: June 2007

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.
1,3‐Aminoalcohols and Their Derivatives in Asymmetric Organic Synthesis
Authors: Lait Susan M. , Rankic Danica A. , Keay Brian A.
Published: June 2007

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.
Phenylselenoethers as Precursors of Acyclic Free Radicals: Creating Tertiary and Quaternary Centers Using Free Radical Based Intermediates
Authors: Cardinal‐David Benoit , Brazeau Jean‐Francois , Katsoulis Ioannins A. , Guindon Yvan
Published: June 2007

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.
Catalytic Asymmetric Epoxidation of Enones and Related Compounds
Authors: Berkessel Albrecht
Published: June 2007

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.
The Nanothreading of Polymers
Authors: Rusa C. C. , Rusa M. , Peet J. , Uyar T. , Fox J. , Hunt M. A. , Wang X. , Balik C. M. , Tonelli A. E.
Published: June 2007

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.
Theoretical Studies on Acetylenic Scaffolds
Authors: Chauvin Remi , Lepetit Christine
Published: June 2007

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.
Cooperative Grid Vortals
Authors: Haupt Tomasz , Kalyanasundaram Anand
Published: June 2007

Vertical Grid portals, or Vortals, proved to be useful by providing access to applications running on high‐performance computational platforms and to distributed data enabling data sharing and other forms of collaboration. This paper identifies the commonalities between Vortals in various application domains, i.e. application‐independent patterns of orchestrating Grid services employed by a typical Vortal. These patterns can be captured as façades—a software layer between the Vortal business logic and generic Grid services that promotes a horizontal integration. The façades are reusable and considerably simplify the development of new Vortals. Furthermore, the façades foster interactions between different Vortals, and hence making them the cooperative Grid Vortals. Copyright © 2007 John Wiley & Sons, Ltd.
Crystallization behaviors of carbon fiber reinforced BN‐Si3N4 matrix composite
Authors: Li Bin , Zhang Chang‐Rui , Wang Si‐Qing , Cao Feng
Published: June 2007

The crystallization behaviors of a new carbon fiber reinforced composite with a hybrid matrix comprising BN and Si3N4 prepared by precursor infiltration and pyrolysis were investigated by Fourier transform infrared spectroscopy, X‐ray diffraction and scanning electron microscopy. The results show that the as‐received composite is almost amorphous, and its main composition is BN and Si3N4. When heat treated at 1600°C, the composite is crystallized and shows a much better crystal form. When heat treated at 2100°C, Si3N4 in the matrix is decomposed, and BN exhibits a relatively complete crystallization. The existence of B4C and SiC is detected, which indicates the interfacial chemical reactions between nitride matrices and carbon fibers. The surface morphology of carbon fibers in the composite changed significantly when heated from 1600 to 2100°C, which also proved the occurrence of interfacial chemical reactions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of crystal thickness of separate confinement heterostructure layers on 1.55‐μm loss‐coupled dfb laser characteristics
Authors: Han Jae‐Ho , Park Sung‐Woong
Published: June 2007

We investigated the effect of the crystal thickness of the separate confinement heterostructure (SCH) guiding layers on the characteristics (threshold current, quantum efficiency) of 1550‐nm loss‐coupled Distributed Feedback laser diode fabricated with a simple step growth having an automatically buried absorptive grating InAsP layer. By increasing the thickness of SCH crystal layers from 40‐nm to 80‐nm in both below and above the multi‐quantum well region, we could achieve lower threshold currents both in 25°C and 85°C with increased ratio of quantum efficiencies between two temperatures. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Luminescence of GaN single crystals prepared by heating a Ga melt in Na–N2 atmosphere
Authors: Yamada Takahiro , Yamane Hisanori , Goto Takenari , Yao Takafumi , Yao Yongzhao , Sekiguchi Takashi
Published: June 2007

Colorless transparent prismatic crystals (0.5‐2.0 mm long) and hopper crystals (1.0‐2.5 mm long) of GaN were prepared by heating a Ga melt at 800°C in Na vapor under N2 pressures of 7.0 MPa for 300 h. The photoluminescence (PL) spectrum of a prismatic crystal at 4 K showed the emission peaks of neutral donor‐bound exciton (D0‐X) and free exciton (XA) at 3.472 eV and 3.478 eV, respectively, in the near band edge region. The full‐width at half‐maximum (FWHM) of (D0‐X) peak was 1.9 meV. The emission peaks of a donor–acceptor pair transition (D0‐A0) and its phonon replicas were observed in a lower energy range (2.9‐3.3 eV). The emission peaks of the D0‐A0 and phonon replicas were also observed in the cathodoluminescence (CL) spectrum at 20 K. The (D0‐X) PL peak of a hopper crystal at 4 K was at 3.474 eV (2.1 meV higher), having a FWHM of 6.1 meV which was over 3 times larger than that of the prismatic crystal. A strong broad band with a maximum intensity around 1.96 eV was observed for the hopper crystals in the CL spectrum at room temperature. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Self‐Consistent Chemical Model of Partially Ionized Hydrogen Plasmas: Electrical Conductivity
Authors: Arkhipov Yu. V. , Baimbetov F. B. , Davletov A. E.
Published: June 2007

The Bogolyubov hierarchy for equilibrium distribution functions is employed to define a chemical model for partially ionized hydrogen plasmas. The Helmholtz free energy is found in a self‐consistent manner beyond the linear mixing rule allowing one to determine not only the ionization equilibrium but the correlation functions as well. Particle interactions are effectively treated such that the charged and neutral components of the plasma are closely interrelated which results in short‐range order formation in the system of interest. The method proposed is an analog of the Debye‐Hückel theory of fully ionized gases and allows one to study both thermodynamics and transport phenomena in a partially ionized hydrogen. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Properties of Hot Dense Plasmas by Orbital‐Free Molecular Dynamics
Authors: Lambert F. , Clérouin J. , Mazevet S. , Gilles D.
Published: June 2007

Quantum Molecular Dynamics simulations (QMD) based on Density Functional Theory (DFT) are now the tool of choice for describing the properties of matter in the warm dense regime (WDM). Thermodynamic and transport properties can be computed for pure phases and mixtures for a wide range of densities ρ0/10 < ρ < 2 – 5ρ0 (where ρ0 is the normal material density) and temperatures 0 < T < 10 eV. The existence of upper bounds in density and temperature is mainly due to the introduction of orbitals for evaluating the electron kinetic energy in the Kohn‐Sham equations. To get rid of this time consuming part of the computation, we propose a model combining, in a consistent way an Orbital Free Density Functional approach based on the Thomas‐Fermi approximation of the electron kinetic energy coupled with classical Molecular Dynamics for the ions (referred as OFMD model).Thanks to an efficient numerical scheme, up to thousand of particles can be propagated leading to accurate static and dynamical properties. Simulations on iron up to 5 keV and boron up to 10 times the normal density were performed. A comparison with linear screening theories using Yukawa's potentials was also done. This method bridges the gap between quantum and classical molecular dynamics in the field of hot‐dense plasmas. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Localization of Coherent Wave Packets in Plasmas due to Decoherence
Authors: Gocke C. , Röpke G.
Published: June 2007

Localization of electron and ion states in a plasma is considered, applying the picture of a test particle in a dissipative environment. The plasma environment is represented by the dielectric function. For the reduced statistical operator a quantum master equation in Born‐Markov‐approximation can be used to quantify the influence of the dissipative background, which gives rise to decoherence and friction. We compare localization of ions due to collisional decoherence with the electronic part with screened interaction and localization by the thermal radiation field. The usual procedure to treat ions classically and electrons as quantum objects is supported by comparing the width of robust states and the mean distance in plasmas. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hydrogen Balmer Spectrum from a High‐Pressure Arc Discharge: Revisited
Authors: Omar B. , Wierling A. , Günter S. , Röpke G.
Published: June 2007

The interpretation of hydrogen Balmer spectra emitted from a high‐pressure arc discharge (Radtke and Günther, Contrib. Plasma Phys. 26, 143 (1986)) is re‐examined. Assuming local thermodynamic equilibrium, synthetic Balmer spectra are calculated for given temperature and density conditions. Radiation transport is accounted for using a one‐dimensional plasma layer model. The lineshape of bound‐bound transitions is determined using a microscopic quantum‐statistical approach. Free‐free and free‐bound contributions are added by taking expressions from literature. Comparing the synthetic spectra with experimental ones, plasma temperature and density conditions are inferred. The plasma parameters are confronted with theoretical results for the compositions of dense plasma. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Properties of Dense Fluid Hydrogen and Helium in Giant Gas Planets
Authors: Vorberger J. , Tamblyn I. , Bonev St. A. , Militzer B.
Published: June 2007

Equilibrium properties of hydrogen‐helium mixtures under thermodynamic conditions found in the interior of giant gas planets are studied by means of density functional theory molecular dynamics simulations. Special emphasis is placed on the molecular‐to‐atomic transition in the fluid phase of hydrogen in the presence of helium. Helium has a substantial influence on the stability of hydrogen molecules. The molecular bond is strengthened and its length is shortened as a result of the increased localization of the electron charge around the helium atoms, which leads to more stable hydrogen molecules compared to pure hydrogen for the same thermodynamic conditions. The ab initio treatment of the mixture enables us to investigate the structure of the liquid and to discuss hydrogen‐hydrogen, helium‐helium, and hydrogen‐helium correlations on the basis of pair correlation functions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Super‐orthogonal space–time trellis codes for two transmit antennas in fast fading channels
Authors: Birol Aslı , Aygölü Ümit
Published: June 2007

Super‐orthogonal space–time trellis codes (SOSTTC) are full rate, full diversity space–time codes with high coding gains for quasi‐static fading channels. In this paper, this design approach is extended to fast fading channels and new SOSTTC are proposed for BPSK and QPSK modulations based on the design criteria valid for this type of channels. The new full rate codes have 4‐ and 16‐state trellises for BPSK and QPSK cases, respectively, to avoid parallel transitions which restrict the error performance. The frame error performances are evaluated through computer simulations and it is shown that the proposed codes have superior performance in the fast fading case compared to their counterparts previously given in the literature for fast and quasi‐static fading channels. Copyright © 2007 John Wiley & Sons, Ltd.
Glutamine synthetase is essential in early mouse embryogenesis
Authors: He Youji , Hakvoort Theodorus B.M. , Vermeulen Jacqueline L.M. , Lamers Wouter H. , Van Roon Maria A.
Published: June 2007

Glutamine synthetase (GS) is expressed in a tissue‐specific and developmentally controlled manner, and functions to remove ammonia or glutamate. Furthermore, it is the only enzyme that can synthesize glutamine de novo. Since congenital deficiency of GS has not been reported, we investigated its role in early development. Because GS is expressed in embryonic stem (ES) cells, we generated a null mutant by replacing one GS allele in‐frame with a β‐galactosidase‐neomycine fusion gene. GS+/LacZ mice have no phenotype, but GSLacZ/LacZ mice die at ED3.5, demonstrating GS is essential in early embryogenesis. Although cells from ED2.5 GSLacZ/LacZ embryos and GSGFP/LacZ ES cells survive in vitro in glutamine‐containing medium, these GS‐deficient cells show a reduced fitness in chimera analysis and fail to survive in tetraploid‐complementation assays. The survival of heavily (>90%) chimeric mice up to at least ED16.5 indicates that GS deficiency does not entail cell‐autonomous effects and that, after implantation, GS activity is not essential until at least the fetal period. We hypothesize that GS‐deficient embryos die when they move from the uterine tube to the harsher uterine environment, where the embryo has to catabolize amino acids to generate energy and, hence, has to detoxify ammonia, which requires GS activity. Developmental Dynamics 236:1865–1875, 2007. © 2007 Wiley‐Liss, Inc.
Pressure segregation methods based on a discrete pressure Poisson equation. An algebraic approach
Authors: Badia Santiago , Codina Ramon
Published: June 2007

In this paper, we introduce some pressure segregation methods obtained from a non‐standard version of the discrete monolithic system, where the continuity equation has been replaced by a pressure Poisson equation obtained at the discrete level. In these methods it is the velocity instead of the pressure the extrapolated unknown. Moreover, predictor–corrector schemes are suggested, again motivated by the new monolithic system. Key implementation aspects are discussed, and a complete stability analysis is performed. We end with a set of numerical examples in order to compare these methods with classical pressure‐correction schemes. Copyright © 2007 John Wiley & Sons, Ltd.
Interrelations between motivational stance, cortical excitability, and the frontal electroencephalogram asymmetry of emotion: A transcranial magnetic stimulation study
Authors: Schutter Dennis J.L.G. , de Weijer Antoin D. , Meuwese Julia D.I. , Morgan Barak , van Honk Jack
Published: June 2007

Several electrophysiological studies have provided evidence for the frontal asymmetry of emotion. In this model the motivation to approach is lateralized to the left, whereas the motivation to avoidance is lateralized to the right hemisphere. The aim of the present experiment was to seek evidence for this model by relating electrophysiological and phenomenological indices of frontal asymmetry to a direct measure of cortical excitability. Frontal asymmetrical resting states of the electroencephalogram and motivational tendencies indexed by the Carver and White questionnaire were compared with neural excitability of the left and right primary motor cortex as assessed by transcranial magnetic stimulation in 24 young healthy right‐handed volunteers. In agreement with the model of frontal asymmetry, predominant left over right frontal cortical excitability was associated with enhanced emotional approach relative to emotional avoidance. Moreover, the asymmetries of brain excitability and approach–avoidance motivational predispositions were both reflected by frontal beta (13–30 Hz) electroencephalogram asymmetries. In conclusion, the currently demonstrated interconnections between cortical excitability, electrophysiological activity, and self‐reported emotional tendencies for approach or avoidance support the frontal asymmetry of emotion model and provide novel insights into its biological underpinnings. Hum Brain Mapp 2008. © 2007 Wiley‐Liss, Inc.
Modulation of cortical oscillatory activity during transcranial magnetic stimulation
Authors: Brignani Debora , Manganotti Paolo , Rossini Paolo M. , Miniussi Carlo
Published: June 2007

Transcranial magnetic stimulation (TMS) can transiently modulate cortical excitability, with a net effect depending on the stimulation frequency (≤1 Hz inhibition vs. ≥5 Hz facilitation, at least for the motor cortex). This possibility has generated interest in experiments aiming to improve deficits in clinical settings, as well as deficits in the cognitive domain. The aim of the present study was to investigate the on‐line effects of low frequency (1 Hz) TMS on the EEG oscillatory activity in the healthy human brain, focusing particularly on the outcome of these modulatory effects in relation to the duration of the TMS stimulation. To this end, we used the event‐related desynchronization/synchronization (ERD/ERS) approach to determine the patterns of oscillatory activity during two consecutive trains of sham and real TMS. Each train of stimulation was delivered to the left primary motor cortex (MI) of healthy subjects over a period of 10 min, while EEG rhythms were simultaneously recorded. Results indicated that TMS induced an increase in the power of brain rhythms that was related to the period of the stimulation, i.e. the synchronization of the α band increased with the duration of the stimulation, and this increase was inversely correlated with motor‐evoked potentials (MEPs) amplitude. In conclusion, low frequency TMS over primary motor cortex induces a synchronization of the background oscillatory activity on the stimulated region. This induced modulation in brain oscillations seems to increase coherently with the duration of stimulation, suggesting that TMS effects may involve short‐term modification of the neural circuitry sustaining MEPs characteristics. Hum Brain Mapp 2008. © 2007 Wiley‐Liss, Inc.
Application of oncogenetic trees mixtures as a biostatistical model of the clonal cytogenetic evolution of meningiomas
Authors: Ketter Ralf , Urbschat Steffi , Henn Wolfram , Feiden Wolfgang , Beerenwinkel Niko , Lengauer Thomas , Steudel Wolf‐Ingo , Zang Klaus D. , Rahnenführer Jörg
Published: June 2007

Meningiomas are mostly benign tumors that originate from the coverings of brain and spinal cord. Typically, they reveal a normal karyotype or monosomy for chromosome 22. Rare clinical progression of meningiomas is associated with a nonrandom pattern of secondary losses of other autosomes. Deletion of the short arm of one chromosome 1 appears to be a decisive step for anaplastic growth in meningiomas. We calculated an oncogenetic tree model that estimates the most likely cytogenetic pathways of 661 meningioma patients in terms of accumulation of somatic chromosome changes in tumor cells. The genetic progression score (GPS) estimates the genetic status of a tumor as progression in the corresponding tumor cells along this model. Large GPS values are highly correlated with early recurrence of meningiomas [p< 10−4]. This correlation holds even if patients are stratified by WHO grade. We show that tumor location also has an impact on genetic progression. Clinical relevance of the GPS is thus demonstrated with respect to origin, WHO grade and recurrence of the tumor. As a quantitative measure the GPS allows a more precise assessment of the prognosis of meningiomas than categorical cytogenetic markers based on single chromosomal aberrations. © 2007 Wiley‐Liss, Inc.
Incidence rates of hepatocellular carcinoma in the U.S. and Denmark: Recent trends
Authors: Jepsen Peter , Vilstrup Hendrik , Tarone Robert E. , Friis Søren , Sørensen Henrik Toft
Published: June 2007

Hepatocellular carcinoma (HCC) incidence rates vary by gender, age, time and place. Geographic differences in gender‐, age‐ and time‐specific HCC incidence rates may improve the understanding of HCC risk factors. We computed annual standardized HCC incidence rates for the United States (U.S.) 1978–2004 and for Denmark 1978–2003. Among U.S. white men aged 45–59 the HCC incidence rates were comparable to the Danish rates until 1995, but more than tripled over the following 8 years to become over 2.5‐fold higher than the Danish rate by 2003, with an additional small increase in 2004. HCC rates in black U.S. men aged 45–59 also increased sharply after 1995. Among women aged 45–59 the U.S. HCC rates were elevated in recent years, but did not show the sharp increase after 1995 observed among men; the Danish rates showed a decreasing trend throughout 1978–2003. U.S. rates in the 60–74 years age groups showed a protracted and gradual increase with no evidence of a sharp increase after 1995. In the 60–74 years age group, rates for Danish men were comparable to those for U.S. white men, but rates for Danish women decreased. The U.S. prevalence rates of hepatitis C virus (HCV) infection are 2.1 and 1.1% for men and women, respectively, the Danish 0.2%. The disparity in HCV prevalence is the most likely explanation for the differences between Danish and U.S. trends in HCC incidence. Intravenous drug use and blood transfusions are the major sources of HCV, and we suggest that increased HCV infection prevalence among Vietnam era military veterans may contribute to the earlier and steeper HCC incidence increase for U.S. men than for U.S. women. © 2007 Wiley‐Liss, Inc.
Suppression of mesangial cell proliferation and extracellular matrix production in streptozotocin‐induced diabetic rats by Sp1 decoy oligodeoxynucleotide in vitro and in vivo
Authors: Kang Jeong Han , Chae Young‐Mi , Park Kwan‐Kyu , Kim Cheorl‐Ho , Lee In‐Seon , Chang Young‐Chae
Published: June 2007

Transcription factor Sp‐1 is an important fibrogenic factor that is involved in the pathogenesis of diabetic nephropathy. In this study, we examined the effect of Sp1 decoy oligodeoxynucleotides (ODNs) on the extracellular matrix (ECM) gene expression in cultured rat mesangial cells (RMC) and streptozotocin (STZ)‐induced diabetic rats. The ring‐type Sp1 decoy ODNs significantly decreased ECM mRNA expression and Sp1 binding to the promoter region of these PDGF‐induced genes in RMC. In addition, the decoy ODNs was introduced into the left renal artery of diabetic rat using the hemagglutinating virus of Japan (HVJ)‐liposome mediated gene transfer method and effectively delivered to the kidney. On 14 days after ring‐type Sp1 decoy ODNs injection, type IV collagen, fibronectin mRNA, and protein expression were markedly decreased, and the rate of urinary creatinine excretion was reduced in the ring‐type Sp1 decoy ODNs‐treated diabetic rats. These results indicated that the ring‐type Sp1 decoy ODNs would be superior to P‐Sp1 ODNs. Also, the R‐Sp1 decoy ODN when introduced in vivo, effectively reduced ECM production during the progression of nephropathy. Therefore, ring‐type Sp1 decoy is a promising tool for developing new therapeutic applications for progressive diabetic nephropathy. J. Cell. Biochem. 103: 663–674, 2008. © 2007 Wiley‐Liss, Inc.
PyFrag—Streamlining your reaction path analysis
Authors: Zeist Willem‐Jan Van , Guerra Célia Fonseca , Bickelhaupt F. Matthias
Published: June 2007

The PyFrag program (released as PyFrag2007.01) is a “wrap‐around” for the Amsterdam Density Functional (ADF) package and facilitates the extension of the fragment analysis method implemented in ADF along an entire potential energy surface. The purpose is to make analyses of reaction paths and other (in principle also multidimensional) potential energy surfaces more transparent and user‐friendly. PyFrag also automates the analysis of reaction paths in terms of the extended activation strain model of chemical reactivity. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
A new detection algorithm for image analysis of single, fluorescence‐labeled proteins in living cells
Authors: Michel René , Steinmeyer Ralf , Falk Michael , Harms Gregory S.
Published: June 2007

A new algorithm is presented for the detection of single, fluorescence‐labeled proteins in the analysis of images from living cells. It is especially suited for images with just a few (<1 per 10 μm2) fluorescence peaks from individual proteins with high background and noise (signal to background ratios as low as 2 and signal to noise as low as 10). The analysis uses the peaks over threshold method from extreme value theory and requires minimal assumptions on the underlying distributions. The significant advantage of the method over others is the rare occurrence to detect false positives. Some examples of simulated and real data are given as comparisons. The algorithm is implemented in MATLAB. Microsc. Res. Tech., 2007. © 2007 Wiley‐Liss, Inc.
Maximum diameter of regular digraphs
Authors: Soares Josè
Published: June 2007

We prove that everyr‐biregular digraph withnvertices has its directed diamter bounded by (3n‐r‐ 3)/(r+1). We show that this bound is tight for directed as well as for undirected graphs. The upper bound remains valid for Eulerian digraphs with minimum outdegreer. © 1929 John Wiley & Sons, Inc.
Directed star decompositions of the complete directed graph
Authors: Colbourn Charles J. , Hoffman D. G. , Rodger C. A.
Published: June 2007

An (s, t)‐directed star is a directed graph with s + t + 1 vertices and s + t arcs; s vertices have indegree zero and outdegree one, t have indegree one and outdegree zero, and one has indegree s and outdegree t. An (s, t)‐directed star decomposition is a partition of the arcs of a complete directed graph of order n into (s, t)‐directed starsx. We establish necessary and sufficient conditions on s, t, and n for an (s, t)‐directed star decomposition of order n to exist.