bluuebunny/crossref_metadata_2025 huggingface dataset:
Cholecystokinin Modulates Migration of Gonadotropin-Releasing Hormone-1 Neurons
Authors: Giacobini Paolo , Kopin Alan S. , Beart Philip M. , Mercer Linda D. , Fasolo Aldo , Wray Susan
Published: May 2004

Expression of the brain–gut peptide cholecystokinin (CCK) in the developing olfactory–gonadotropin-releasing hormone-1 (GnRH-1) neuroendocrine systems was characterized, and the function of CCK in these systems was analyzed bothin vivoandin vitro. We present novel data demonstrating that CCK transcript and protein are expressed in sensory cells in the developing olfactory epithelium and vomeronasal organ, with both ligand and receptors (CCK-1R and CCK-2R) found on olfactory axons throughout prenatal development. In addition, migrating GnRH-1 neurons in nasal regions express CCK-1R but not CCK-2R receptors. The role of CCK in olfactory–GnRH-1 system development was evaluated using nasal explants, after assessing that thein vivoexpression of both CCK and CCK receptors was mimicked in thisin vitromodel. Exogenous application of CCK (10-7m) reduced both olfactory axon outgrowth and migration of GnRH-1 cells. This inhibition was mediated by CCK-1R receptors. Moreover, CCK-1R but not CCK-2R antagonism caused a shift in the location of GnRH-1 neurons, increasing the distance that the cells migrated. GnRH-1 neuronal migration in mice carrying a genetic deletion of either CCK-1R or CCK-2R receptor genes was also analyzed. At embryonic day 14.5, the total number of GnRH-1 cells was identical in wild-type and mutant mice; however, the number of GnRH-1 neurons within forebrain was significantly greater in CCK-1R–/–embryos, consistent with an accelerated migratory process. These results indicate that CCK provides an inhibitory influence on GnRH-1 neuronal migration, contributing to the appropriate entrance of these neuroendocrine cells into the brain, and thus represent the first report of a developmental role for CCK.
Block of AMPA Receptor Desensitization by a Point Mutation outside the Ligand-Binding Domain
Authors: Yelshansky Maria V. , Sobolevsky Alexander I. , Jatzke Claudia , Wollmuth Lonnie P.
Published: May 2004

Desensitization of ionotropic glutamate receptors (GluRs), specifically the AMPA receptor subtype, shapes the postsynaptic response at certain synapses in the brain. All known mechanisms that alter desensitization, either pharmacological or mutational, are associated with the ligand-binding domain. Here we report that substitution of a conserved positively charged arginine (R) with a negatively charged glutamate in the linker between the pore-forming M3 segment and the S2 lobe, a region outside the ligand-binding domain, blocks desensitization in homomeric AMPA receptors composed of GluR-Bisubunits. A charge-reversing substitution of a glutamate adjacent to this conserved R enhanced desensitization, consistent with these effects attributable to electrostatics. Homologous substitutions of the conserved R in GluR-Bo, GluR-Aiand the kainate receptor GluR-6 subunits produced comparable but less visible effects on desensitization. Subunit specificity was also apparent for accessibility of substituted cysteines in the M3–S2 linker, suggesting that this part of the channel is not structurally identical in different GluRs. Additionally, reactivity with a sulfhydryl-specific reagent was state dependent, suggesting that the conformations of the nonconducting closed and desensitized states are different at the level of the M3–S2 linker. Our results therefore represent the first identification of elements outside the ligand-binding domain affecting desensitization in non-NMDA receptor channels and suggest that electrostatic interactions involving charged residues in the M3–S2 linker influence channel gating in a subunit- and subtype-specific manner.
Acceleration of Visual System Development by Environmental Enrichment
Authors: Cancedda Laura , Putignano Elena , Sale Alessandro , Viegi Alessandro , Berardi Nicoletta , Maffei Lamberto
Published: May 2004

Thus far, the developmental plasticity of the visual system has been studied by altering or reducing visual experience. Here, we investigated whether a complex sensory-motor stimulation, provided by rearing animals in an enriched environment, affects visual system development. We found that raising mice in this condition causes an earlier eye opening, a precocious development of visual acuity, and an accelerated decline of white matter-induced long-term potentiation. These effects are accompanied by a precocious cAMP response element-mediated gene expression and a significant increase of BDNF protein and GAD65/67 expression in enriched pups. In addition, we showed that enriched pups experienced higher levels of licking behavior provided by adult females. Thus, rearing mice from birth in an enriched environment leads to a conspicuous acceleration of visual system development as ascertained at behavioral, electrophysiological, and molecular level.
Rapid Maxillary Expansion after Secondary Alveolar Bone Graft in a Patient with Bilateral Cleft Lip and Palate
Authors: de Oliveira Cavassan Arlete , de Albuquerque Marcelo D'Albuquerque , Capelozza Filho Leopoldino
Published: May 2004

Objective

To verify the effects of rapid maxillary expansion performed after secondary alveolar bone graft in one patient.

Setting

Department of Orthodontics of the Hospital for Rehabilitation of Craniofacial Anomalies, University of Sao Paulo.

Patient(s)

The patient had bilateral cleft lip and palate, had already had a bone graft, and showed a relapsing maxillary constriction in need of correction.

Intervention

A fixed dental-mucous-bone-supported expander corrected the maxillary constriction.

Main Outcome Measure(s)

Measurements were obtained from dental casts, including transverse dimensions (intercanine distance [IC], interfirst premolar distance [IP], and interfirst molar distance [IM]) and measurements of the grafted area (interfirst premolar/central incisors [IPI] and interfirst premolar/canine [IPC]) to observe the changes. Clinical and radiographic analyses were done through direct view.

Results

The occlusal radiograph of the maxilla after expansion showed opening of the intermaxillary suture in the premaxillary area, which was clinically confirmed by the diastema between the maxillary central incisors. No radiographic alteration was observed in the grafted area. The transverse measurements of the dental casts (IC, IP, and IM) showed a significant increase. The measurements of the teeth adjacent to the grafted area, IPI and IPC, increased.

Conclusions

The orthopedic effect of rapid maxillary expansion after bone graft was verified. Nevertheless, additional studies are necessary to define any side effects in patients submitted to bone graft.
Three-Dimensional Analysis of Maxillary and Mandibular Growth Increments
Authors: Lux Christopher J. , Conradt Christian , Burden Donald , Komposch Gerda
Published: May 2004

Objective

To analyze changes in the facial, maxillary, and mandibular skeleton in the vertical, sagittal, and transverse dimensions during an orthodontically relevant period of dentofacial development (i.e., between 7 and 15 years of age).

Subjects and Method

This longitudinal study comprised posteroanterior (PA) and lateral cephalograms at 7, 9, 11, 13, and 15 years of 18 untreated Class I subjects with good occlusion. Transverse growth (width) was analyzed on the basis of PA cephalograms and sagittal (depth) and vertical (height) growth by means of lateral cephalograms. For each linear measurement, mean percentage increases were calculated relative to the size at 7 years of age.

Results and Conclusions

Between 7 and 15 years of age, in the whole facial skeleton and the maxilla, percentage increases were most pronounced in the vertical dimension when compared with the sagittal and transverse dimensions. In the mandible, the largest percentage increases were found in both sexes for vertical growth of the ramus, followed by sagittal growth (body length) and then mandibular width. In the sagittal dimension, development was more pronounced in the mandible (at pogonion more than at B point) than in the maxilla (A point). With respect to vertical growth, percentage increases in posterior face height exceeded the increases in anterior face height. When facial shape changes were analyzed between 7 and 15 years of age in both sexes, the ratio facial height/facial width increased and the ratio facial depth/ facial height decreased, which points toward an age-related increasing influence of vertical development.
Intracellular Delivery of Quantum Dots for Live Cell Labeling and Organelle Tracking
Authors: Derfus A. M. , Chan W. C. W. , Bhatia S. N.
Published: May 2004

Several strategies borrowed from the field of gene delivery are adapted to enhance delivery of semiconductor quantum dots (QDs) to the interior of live cells. To traffic QDs to subcellular organelles, QDs were then derivatized with known peptide localization sequences, demonstrating the ability to target QDs to the nucleus and mitochondria (see Figure).
Organic Polarized Light‐Emitting Diodes via Förster Energy Transfer Using Monodisperse Conjugated Oligomers
Authors: Chen A. C. A. , Culligan S. W. , Geng Y. , Chen S. H. , Klubek K. P. , Vaeth K. M. , Tang C. W.
Published: May 2004

A heptafluorene lightly doped with monodisperse conjugated oligomersis used for the first demonstration of organic polarized (see Figure) light‐emitting diodes utilizing Förster energy transfer. Emission of blue‐green, green, red, and white light is accomplished with a turn‐on voltage of < 4 V, peak polarization ratios of up to 26, integrated polarization ratios of up to 19, and luminance yields of up to 6.4 cd A–1.
Zeolite Coatings on Microcellular Ceramic Foams: A Novel Route to Microreactor and Microseparator Devices
Authors: Zampieri A. , Colombo P. , Mabande G. T. P. , Selvam T. , Schwieger W. , Scheffler F.
Published: May 2004

A novel zeolite–ceramic composite monolith with a hierarchical bimodal (nano‐, macroscale) pore system (see Figure) has been prepared by coating the internal cell walls of microcellular polymer‐derived ceramic foams (cell size ∼ 8 μm) with a thin layer of MFI‐type zeolite. Applications are envisaged as microreactors and microseparator devices for catalysis and adsorption/ separation because of the material's unique microstructural design.
Effect of Phase Retardation on Defect‐Mode Lasing in Polymeric Cholesteric Liquid Crystals
Authors: Song M. H. , Park B. , Shin K.‐C. , Ohta T. , Tsunoda Y. , Hoshi H. , Takanishi Y. , Ishikawa K. , Watanabe J. , Nishimura S. , Toyooka T. , Zhu Z. , Swager T. M. , Takezoe H.
Published: May 2004

Lasing via a phase retardation defect modeis reported for the first time. The Figure shows the far‐field pattern of laser emission realized by inserting an anisotropic nematic liquid crystal (LC) defect layer between polymer cholesteric LC layers. The system mimics the cuticle ofPlusiotis resplendens, a beetle, using the birefringence of the anisotropic layer to achieve reflectance greater than the 50 % provided by simple cholesteric LC photonic bandgaps.
Dendrimers in Solution: Insight from Theory and Simulation
Authors: Ballauff Matthias , Likos Christos N.
Published: May 2004

A variety of experimental and theoretical approaches show that, akin to linear polymers, dendrimers in good solvent conditions are best described as flexible macromolecular aggregates with a dense core and fluctuating monomer groups. We present theoretical and simulational evidence of how the shape and inner structure of dendrimers depends on the generation number as well as the effective interactions that exist between dendrimers in solution. These approaches based on simplified dendritic structures show there is a tunable and ultrasoft interaction between the centers of the solublized dendrimers. Results from small‐angle neutron scattering data confirm the theory and indicate that dendrimers are model systems of ultrasoft colloids that bridge the gap between polymers and hard spheres. Dendrimers can form a class of materials analogous to the related systems of star polymers and block copolymer micelles which exhibit special properties.
On the Structure of Liquid Hydrogen Fluoride.
Authors: McLain Sylvia E. , Benmore Chris J. , Siewenie Joan E. , Urquidi Jacob , Turner John F. C.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Structure of the UO22+—SO42‐ Ion Pair in Aqueous Solution.
Authors: Neuefeind J. , Skanthakumar S. , Soderholm L.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
The Crystal Structure of a New Low Temperature Modification of In3Ir.
Authors: Flandorfer Hans
Published: May 2004

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Ternary System Tm—Cu—Ge: Isothermal Section of the Phase Diagram at 870 K and Crystal Structures of the Compounds.
Authors: Fedyna L. O. , Bodak O. I. , Tokaychuk Ya. O. , Fedyna M. F. , Mokra I. R.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
The Growth and Spectroscopic Characteristics of Ca3Y2(BO3)4:Tm3+ Crystal.
Authors: Tu Chaoyang , Wang Yan , You Zhenyu , Li Jianfu , Zhu Zhaojie , Wu BaiChang
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Rietveld Analysis for Eu2+ Doped 4SrO×7Al2O3 and Its Luminescent Properties.
Authors: Yuan Zhao‐Xin , Chang Cheng‐Kang , Mao Da‐Li
Published: May 2004

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The AgGaS2 + 2CdSe ↔ AgGaSe2 + 2CdS System
Authors: Olekseyuke I. D. , Husak O. A. , Gulay L. D. , Farasyuk O. V.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Phase Equilibria in the Quasi‐Ternary System Cu2Se—CdSe—In2Se3.
Authors: Zmiy O. F. , Mishchenko I. A. , Olekseyuk I. D.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Rechargeable Fe(III)/(VI) Super‐Iron Cathodes.
Authors: Licht Stuart , Tel‐Vered Ran
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
On the Characterization of La1.5Mg17Ni0.5 Composite Materials Prepared by Hydriding Combustion Synthesis.
Authors: Li Qian , Lin Qin , Jiang Lijun , Chou Kuo‐Chih
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Gd5Si2B8: A Ternary Rare‐Earth‐Metal Silicide Boride Compound.
Authors: Babizhetskyy Volodymyr , Roger Jerome , Deputier Stephanie , Guerin Roland , Jardin Regis , Bauer Josef , Hiebl Kurt , Jardin Christophe , Saillard Jean‐Yves , Halet Jean‐Francois
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis and Oxidation of Nanocrystalline HfB2.
Authors: Chen Luyang , Gu Yunle , Shi Liang , Yang Zeheng , Ma Jianhua , Qian Yitai
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
First Isolated Active Titanium Peroxo Complex: Characterization and Theoretical Study.
Authors: Kholdeeva Oxana A. , Trubitsina Tatiana A. , Maksimovskaya Raisa I. , Golovin Anatolii V. , Neiwert Wade A. , Kolesov Boris A. , Lopez Xavier , Poblet Josep M.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Boc‐L‐proline as a New Chiral Ligand for Enantioselective Phenylacetylene Addition to Aromatic Aldehydes.
Authors: Zhou Yu‐feng , Wang Rui , Xu Zhao‐qing , Yan Wen‐jin , Liu Lei , Gao Yan‐feng , Da Chao‐shan
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
(S)‐Serine Derived N—O and N—P Oxazoline Ligands for Asymmetric Catalysis.
Authors: Jones Geraint , Richards Christopher J.
Published: May 2004

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Substitution of β‐Nitrostyrenes by Electrophilic Carbon‐Centered Radicals.
Authors: Garcia‐Torres Alejandro , Cruz‐Almanza Rymundo , Miranda Luis D.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Aza‐Baylis—Hillman Reactions of Diisopropyl Azodicarboxylate or Diethyl Azodicarboxylate with Acrylates and Acrylonitrile.
Authors: Shi Min , Zhao Gui‐Ling
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Cyclizations of N‐Stannylaminyl Radicals onto Nitriles.
Authors: Benati Luisa , Bencivenni Giorgio , Leardini Rino , Minozzi Matteo , Nanni Daniele , Scialpi Rosanna , Spagnolo Piero , Zanardi Giuseppe , Rizzoli Corrado
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
High Yield Synthesis of Aryl Cyanides under Microwave Irradiation.
Authors: Ghaffarzadeh Mohammad , Bolourtchian Mohammad , Halvagar Mohammad Reza , Hosseini Maryam
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Hydrogen Transfer Reduction of Aldehydes with Alkali‐Metal Carbonates and Iridium NHC Complexes
Authors: Miecznikowski John R. , Crabtree Robert H.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Stille Coupling Made Easier — The Synergic Effect of Copper(I) Salts and the Fluoride Ion.
Authors: Mee Simon P. H. , Lee Victor , Baldwin Jack E.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Direct Copper(I) Iodide Dimethyl Sulfide Catalyzed Conjugate Addition of Alkenyl Groups from Vinylzirconocene Reagents.
Authors: El‐Batta Amer , Hage Taleb R. , Plotkin Steve , Bergdahl Mikael
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of a Novel Silicon Bearing Linker for Solid Phase Synthesis.
Authors: Ramage Robert , Andrews Martin J. I. , Raphy Jenny , Wang Pu
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Oxonitriles: Multicomponent Grignard Addition‐Alkylations.
Authors: Fleming Fraser F. , Zhang Zhiyu , Wang Qunzhao , Steward Omar W.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
An Unusually Robust Triple Bond: Synthesis, Structure and Reactivity of 3‐Alkynylcyclopropenes.
Authors: Gilbertson Robert D. , Wu He‐Ping , Gorman‐Lewis Drew , Weakley Timothy J. R. , Weiss Hans‐Christoph , Boese Roland , Haley Michael M.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Catalytic [2 + 2]‐Cycloaddition Reactions of Silyl Enol Ethers. A Convenient and Stereoselective Method for Cyclobutane Ring Formation.
Authors: Takasu Kiyosei , Ueno Megumi , Inanaga Kazato , Ihara Masataka
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Efficient Oxidative Radical Cyclizations of Ester Enolates with Carbocation Desilylation as Termination: Synthesis of Cyclopentanoid Monoterpenes and Analogues.
Authors: Jahn Ullrich , Hartmann Philip , Kaasalainen Emmi
Published: May 2004

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Metalated Nitriles: Halogen—Metal Exchange with α‐Halonitriles.
Authors: Fleming Fraser F. , Zhang Zhiyu , Knochel Paul
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Efficient Medium‐Ring Cyclization under Non‐High‐Dilution Conditions Using SmI2.
Authors: Tamiya Hiroaki , Goto Kazuhiro , Matsuda Fuyuhiko
Published: May 2004

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Eco‐Friendly Oxidative Iodination of Various Arenes with a Urea‐Hydrogen Peroxide Adduct (UHP) as the Oxidant.
Authors: Lulinski Piotr , Kryska Anna , Sosnowski Maciej , Skulski Lech
Published: May 2004

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Structural Revision of the Ring‐Opened Product in the ZnCl2‐Catalyzed Reactions of 1‐Benzyl‐2‐phenylaziridine with Thiols.
Authors: Furuta Yukiko , Kumamoto Takuya , Ishikawa Tsutomu
Published: May 2004

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New S,O‐Acetals from (1R)‐(‐)‐Myrtenal as Chiral Auxiliaries in Nucleophilic Additions.
Authors: Chacon‐Garcia Luis , Lagunas‐Rivera Selene , Perez‐Estrada Salvador , Vargas‐Diaz M. Elena , Joseph‐Nathan Pedro , Tamariz Joaquin , Zepeda L. Gerardo
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Oxidation of Toluenes to Benzoic Acids by Oxygen in Non‐acidic Solvents.
Authors: Yang Fan , Sun Jing , Zheng Rui , Qiu Wenwei , Tang Jie , He Mingyuan
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of β‐Substituted α‐Amino Acids via Lewis Acid Promoted Radical Conjugate Additions to α,β‐Unsaturated α‐Nitro Esters and Amides.
Authors: Srikanth G. S. C. , Castle Steven L.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of a Novel C2‐Symmetric Thiourea and Its Application in the Pd‐Catalyzed Cross‐Coupling Reactions with Arenediazonium Salts under Aerobic Conditions.
Authors: Dai Mingji , Liang Bo , Wang Cuihua , Chen Jiahua , Yang Zhen
Published: May 2004

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Homocoupling of 1‐Alkynyl Tosylamides.
Authors: Rodriguez David , Castedo Luis , Saa Carlos
Published: May 2004

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A New and Efficient Method for the Synthesis of Trifluoromethylthio‐ and Selenoethers.
Authors: Pooput Chaya , Medebielle Maurice , Dolbier William R. Jr.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Pinacol‐Pinacolone Rearrangement on FeCl3 Modified Montmorillonite K10.
Authors: Shinde Ajit B. , Shrigadi Nilesh B. , Bhat Ramakrishna P. , Samant Shriniwas D.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Stereoselective Synthesis of Heterosubstituted Aziridines and Their Functionalization.
Authors: De Vitis Luisella , Florio Saverio , Granito Catia , Ronzini Ludovico , Troisi Luigino , Capriati Vito , Luisi Renzo , Pilati Tullio
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Oxone®‐KI Induced Lactonization and Etherification of Unsaturated Acids and Alcohols: A Formal Synthesis of Mintlactone.
Authors: Curini Massimo , Epifano Francesco , Marcotullio M. Carla , Montanari Francesca
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Aminoalkylation with Aldehydes Mediated by Solid Lithium Perchlorate.
Authors: Saidi Mohammad R. , Nazari Mohammad
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
A Flexible Approach for the Asymmetric Synthesis of N‐Protected (R)‐5‐Alkyl Tetramates and (R)‐5‐Alkyl Tetramic Acid Derivatives.
Authors: Huang Pei‐Qiang , Deng Jun
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Dimer of Trifluoropyruvic Acid: Synthesis and Molecular Structure.
Authors: Sevenard Dmitri V. , Loop Ildiko , Lork Enno , Breuer Eli , Roeschenthaler Gerd‐Volker
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Unusual Thermolysis of Diisobutyl Polysulfides.
Authors: Korchevina N. A. , Sukhomazova E. N. , Deryagina E. N.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Preparation of Novel 1,2,3‐Triazoles and a Comparative Study Involving Two Recent Methods for 1,2,3‐Triazole Synthesis.
Authors: Melo Julio Onesio Ferreira , Ratton Patricia Melo , Augusti Rodinei , Donnici Claudio Luis
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis and Antibiotic Activity of the Tricyclic Furo[3,2‐c] Isochromen‐2‐trione Unit of the Pyranonaphthoquinones.
Authors: Bianchi Dario A. , Sutich Emma G. , Kaufman Teodoro S.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Bromination and Azidation Reactions of 2‐Styrylchromones. New Syntheses of 4(5)‐Aryl‐5(4)‐(2‐chromonyl)‐1,2,3‐triazoles.
Authors: Silva Artur M. S. , Vieira Judite S. , Brito Cristela M. , Cavaleiro Jose A. S. , Patonay Tamas , Levai Albert , Elguero Jose
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
A Novel Cascade Reaction of Aryl Aldoxime with Dimedone under Microwave Irradiation: The Synthesis of N‐Hydroxylacridine.
Authors: Tu Shujiang , Miao Chunbao , Gao Yuan , Fang Fang , Zhuang Qiya , Feng Youjian , Shi Daqing
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Reactions of 1‐[Benzoyl(2‐hetaroyl)]‐2,2‐dimethylhydrazines with 1,3‐Dibromopropyne, 2‐Propynyl Bromide, and Allyl Bromide.
Authors: Nakhmanovich A. S. , Karnaukhova R. V. , Larina L. I. , Ushakov P. E. , Lopyrev V. A.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of N,N′‐Disubstituted 3‐Aminobenzo[c] and [d]Azepin‐2‐ones as Potent and Specific Farnesyl Transferase Inhibitors.
Authors: Le Diguarher Thierry , Ortuno Jean‐Claude , Shanks David , Guilbaud Nicolas , Pierre Alain , Raimbaud Eric , Fauchere Jean‐Luc , Hickman John A. , Tucker Gordon C. , Casara Patrick J.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
A Novel Synthesis of (E)‐gem‐Dimetalloalkenes Containing Boron and Silicon: An Easy Access to Alkyl Trimethylsilyl Ketones.
Authors: Bhat Narayan G. , Tamm Amanda , Gorena Amanda
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of New α‐ or γ‐Functionalized Hydroxymethylphosphinic Acid Derivatives.
Authors: Cristau Henri‐Jean , Herve Agnes , Virieux David
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Direct Conversion of sec‐Phosphine Oxides into Phosphinous Acid‐Boranes.
Authors: Stankevic Marek , Andrijewski Grzegorz , Pietrusiewicz K. Michal
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of Symmetrical Methylenebis(alkyl hydrogen phosphonates) by Selective Cleavage of Methylenebis(dialkyl phosphonates) with Morpholine.
Authors: Reddy Gantla Vidyasagar , Jacobs Hollie K. , Gopalan Aravamudan S. , Barrans Richard E. Jr. , Dietz Mark L. , Stepinski Dominique C. , Herlinger Albert W.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Carbonylation of Lithium Enolates with Carbon Monoxide Mediated by Selenium.
Authors: Fujiwara Shin‐ichi , Nishiyama Akira , Shin‐ike Tsutomu , Kambe Nobuaki , Sonoda Noboru
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Chemical Composition and Antitumor Activities from Givotia madagascariensis.
Authors: Krebs Hans C. , Duddeck Helmut , Malik Shahid , Beil Winfried , Rasoanaivo Philippe , Andrianarijaona Mamy
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
An Efficient Alternative Synthesis of (+)‐(6S,7S)‐7‐Hydroxy‐6,11‐cyclofarnes‐3(15)‐en‐2‐one, the (S)‐Enantiomer of the Antibacterial Sesquiterpene from Premna oligotricha.
Authors: Nozawa Masato , Hoshi Takashi , Suzuki Toshio , Hagiwara Hisahiro
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Chemoselective Glycosylations Using Sulfonium Triflate Activator Systems.
Authors: Codee Jeroen D. C. , van den Bos Leendert J. , Litjens Remy E. J. N. , Overkleeft Herman S. , van Boeckel Constant A. A. , van Boom Jacques H. , van der Marel Gijs A.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Moisture‐Stable Promoters for Selective α‐Fucosylation Reactions: Synthesis of Antigen Fragments.
Authors: Adinolfi Matteo , Iadonisi Alfonso , Ravida Alessandra , Schiattarella Marialuisa
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Improved Procedure for the Selective N‐Debenzylation of Benzylamines by Diisopropyl Azodicarboxylate.
Authors: Kroutil Jiri , Trnka Tomas , Cerny Miloslav
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Synthetic Studies on Natural Products. Part 19. A Convenient Method for the Preparation of 7‐Cyanocamptothecins (II) and 7‐Cyanomappicine Ketones (III)
Authors: Das Biswanath , Srinivas K. V. N. S. , Mahender I. , Ravindranath N. , Ramesh C.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis and Biological Evaluation of (‐)‐Laulimalide Analogues.
Authors: Gallagher Brian M. Jr. , Fang Francis G. , Johannes Charles W. , Pesant Marc , Tremblay Martin R. , Zhao Hongjuan , Akasaka Kozo , Li Xiang‐yi , Liu Junke , Littlefield Bruce A.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis and Preliminary Antimicrobial Evaluation of New 7‐(N‐Pyrrolyl) Derivatives of Cephalosporins.
Authors: Bijev Atanas , Nankov Atanas , Keuleyan Emma , Markovska Rumiana , Daneva Elitsa
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
Citrafungins A and B, Two New Fungal Metabolite Inhibitors of GGTase I with Antifungal Activity.
Authors: Singh Sheo B. , Zink Deborah L. , Doss George A. , Polishook Jon D. , Ruby Carolyn , Register Elizabeth , Kelly Theresa M. , Bonfiglio Cynthia , Williamson Joanne M. , Kelly Rosemarie
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
A Convergent Synthesis of the Macrocyclic Core of Cytotrienins: Application of RCM for Macrocyclization.
Authors: Evano Gwilherm , Schaus Jennifer V. , Panek James S.
Published: May 2004

For Abstract see ChemInform Abstract in Full Text.
First Total Synthesis of Murisolin.
Authors: Maezaki Naoyoshi , Tominaga Hiroaki , Kojima Naoto , Yanai Minori , Urabe Daisuke , Tanaka Tetsuaki
Published: May 2004

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Magnetization Reversal by Quantum Tunneling in Nanometer‐sized Particles and Clusters
Authors: Wernsdorfer Wolfgang
Published: May 2004

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Mesostructured Solid Acids
Authors: Hamoudi S. , On D. Trong , Kaliaguine S.
Published: May 2004

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LixNi1‐xO (0 < x ≤ 0.3) Solid Solutions: Formation, Structure and Transport Properties
Authors: Antolini Ermete
Published: May 2004

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Revelations in Dinitrogen Activation and Functionalization by Metal Complexes
Authors: Kozak Christopher M. , Mountford Philip
Published: May 2004

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Proton Transfer to Organometallic Hydrides via Unconventional Hydrogen Bonding: Problems and Perspectives
Authors: Belkova N. V. , Gutsul E. I. , Shubina E. S. , Epstein L. M.
Published: May 2004

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Metallaboranes and Metallacarboranes of S‐and P‐Block Elements
Authors: Rana Geeta , Vyakaranam Kamesh , Maguire John A. , Hosmane Narayan S.
Published: May 2004

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Synthesis of Piperidines
Authors: Buffat Maxime G. P.
Published: May 2004

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N‐Acylhydrazines: Future Perspectives Offered by New Syntheses and Chemistry
Authors: Licandro Emanuela , Perdicchia Dario
Published: May 2004

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The Use of N‐Boc‐1,3‐Oxazolidines as Chiral Auxiliaries in Asymmetric Synthesis
Authors: Agami Claude , Couty Francois
Published: May 2004

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Old Codons, New Amino Acids
Authors: Hahn Ulrich , Palm Gottfried J. , Hinrichs Winfried
Published: May 2004

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Synthesis and Properties of Allenic Natural Products and Pharmaceuticals
Authors: Hoffmann‐Roeder Anja , Krause Norbert
Published: May 2004

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H1‐Histamines: Pharmacological Basis of Their Activity
Authors: Dittmann Andreas , Mohr Klaus
Published: May 2004

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Nucleophilic Ring Opening of Aziridines
Authors: Hu X. Eric
Published: May 2004

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Supramolecular Chemistry
Authors: Gale Philip A.
Published: May 2004

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Transition Metals in Organic Synthesis. Part 1. Catalytic Applications
Authors: Fairlamb Ian. J. S.
Published: May 2004

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Synthetic Methods. Part 3. Biocatalysis and Enzymes in Organic Synthesis
Authors: Davis Benjamin G.
Published: May 2004

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Recent Developments in Rhodium‐Catalyzed Allylic Substitution and Carbocyclization Reactions
Authors: Evans P. Andrew , Leahy David K.
Published: May 2004

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Nucleophilic Activation of Enones via Homogeneous Catalytic Hydrogenation: Catalytic Reductive C—C Bond Formation under Hydrogenation Conditions
Authors: Jang Hye‐Young , Huddleston Ryan R. , Krische Michael J.
Published: May 2004

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Ammonium, Oxonium and Sulfonium Ylides—Generation of Sulfonium Ylides from Carbenes and Carbenoids
Authors: Ando Wataru , Matsuyama Haruo
Published: May 2004

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Ammonium, Oxonium and Sulfonium Ylides—Generation of Sulfur Ylides from Metal Carbenoids
Authors: Davies Huw M. L.
Published: May 2004

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Hydrazide‐Based Hypercoordinate Silicon Compounds
Authors: Kost Daniel , Kalikhman Inna
Published: May 2004

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New Synthetic Protocol in Organic Synthesis: Catalytic Functionalization of Unreactive C—H Bonds
Authors: Kakiuchi Fumitoshi
Published: May 2004

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Molecular Design and Development of Potassium Channel Blockers
Authors: Kaiho Tatsuo , Miyamoto Michihiko , Nobori Tadahito , Katakami Tsutomu
Published: May 2004

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Chemistry of Structurally Confused Kinamycins
Authors: Kumamoto Takuya , Ishikawa Tsutomu , Omura Satoshi
Published: May 2004

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Development of the First Spiro Bis(isoxazoline) Ligands (SPRIXs) and Their Applications to Catalytic Enantioselective Reactions
Authors: Arai Midori A. , Shinohara Toshio , Arai Takayoshi , Sasai Hiroaki
Published: May 2004

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Selective Optimization of Side Activities: Another Way for Drug Discovery
Authors: Wermuth Camille G.
Published: May 2004

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Cyclizations of N‐Acyliminium Ions
Authors: Maryanoff Bruce E. , Zhang Han‐Cheng , Cohen Judith H. , Turchi Ignatius J. , Maryanoff Cynthia A.
Published: May 2004

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Mixed Phosphine—Phosphine Oxide Ligands
Authors: Grushin Vladimir V.
Published: May 2004

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Supramolecular Host—Guest Systems in Zeolites Prepared by Ship‐in‐a‐Bottle Synthesis
Authors: Corma Avelino , Garcia Hermenegildo
Published: May 2004

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Camptothecin: Current Perspectives
Authors: Thomas Craig J. , Rahier Nicolas J. , Hecht Sidney M.
Published: May 2004

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Cyclopropylstannanes: Synthesis and Applications
Authors: Rubina Marina , Gevorgyan Vladimir
Published: May 2004

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Chemistry in Motion—Unidirectional Rotating Molecular Motors
Authors: Mandl Christian P. , Koenig Burkhard
Published: May 2004

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ω‐Conotoxins and Approaches to Their Non‐Peptide Mimetics.
Authors: Baell Jonathan B. , Duggan Peter J. , Lok Y. Phei
Published: May 2004

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Photochemical Cycloaddition Between Benzene Derivatives and Alkenes
Authors: Hoffmann Norbert
Published: May 2004

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Molybdenum‐Catalyzed Asymmetric Allylic Alkylations
Authors: Belda Oscar , Moberg Christina
Published: May 2004

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Asymmetric Synthesis and Organometallic Chemistry of Functionalized Phosphines Containing Stereogenic Phosphorus Centers
Authors: Leung Pak‐Hing
Published: May 2004

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Syntheses of Heterocyclic Compounds under Microwave Irradiation
Authors: Xu Yu , Guo Qing‐Xiang
Published: May 2004

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Water‐Soluble Porphyrins and Their Metal Complexes
Authors: Makarska M. , Radzki S.
Published: May 2004

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The Chemical Total Synthesis of Proteins
Authors: Seitz Oliver
Published: May 2004

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Heterogeneous Catalytic Transfer Hydrogenation in Peptide Synthesis
Authors: Gowda D. Channe , Abiraj K.
Published: May 2004

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Extending Chemoselective Ligation to Sugar Chemistry: Convergent Assembly of Bioactive Neoglycoconjugates
Authors: Peri Francesco
Published: May 2004

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α‐Amino Acids and Derivatives in the Asymmetric Synthesis of Tetrahydroisoquinoline Alkaloids
Authors: Vicario Jose L. , Badia Dolores , Carrillo Luisa , Etxebarria Juan
Published: May 2004

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A Pyridylsilyl Group Expands the Scope of the Intermolecular Pauson—Khand Reactions
Authors: Preston Adam J. , Parquette Jon R.
Published: May 2004

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Mesoporous Solids for Green Chemistry
Authors: Clark James H.
Published: May 2004

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Peptide Chemistry at Degussa Fine Chemicals
Authors: Knaup Guenter , Mueller Thomas , Schwarm Michael
Published: May 2004

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Industrial Application of Coupling Reagents in Peptides
Authors: Marder Oleg , Albericio Fernando
Published: May 2004

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Fructose‐Permeable Liquid Membranes Containing Boronic Acid Carriers
Authors: Duggan Peter J.
Published: May 2004

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Collisional Activation of Peptide Ions in FT‐ICR Mass Spectrometry
Authors: Laskin Julia , Futrell Jean H.
Published: May 2004

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A Dozen Carborane Structures Refined by Comparison of Quantum Chemical Calculated and Experimental NMR Chemical Shift Values
Authors: Williams Robert E.
Published: May 2004

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Exploring Dynamics in the Far‐Infrared with Terahertz Spectroscopy
Authors: Schmuttenmaer Charles A.
Published: May 2004

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Ultrafast Dynamics of Carotenoid Excited States — From Solution to Natural and Artificial Systems
Authors: Polivka Tomas , Sundstroem Villy
Published: May 2004

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Dynamics of Water in Biological Recognition
Authors: Pal Samir Kumar , Zewail Ahmed H.
Published: May 2004

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Performance improvement of TCP over an ad hoc network
Authors: Yuki Taichi , Yamamoto Takayuki , Sugano Masashi , Murata Masayuki , Miyahara Hideo , Hatauchi Takaaki
Published: May 2004

FRN (flexible radio network) is an ad hoc network product that can realize a wide‐area data collection network. This paper discusses a performance improvement method when TCP is applied to the transport layer in FRN. It is shown that even when the terminal is not moving as in FRN, the throughput can be improved in radio link failure due to noise or obstacles by combining ELFN (explicit link failure notification), which is proposed as a method for TCP performance improvement in ad hoc networks, with routing information. The proposed method is evaluated by simulation in this paper. A further objective is to reduce the performance degradation due to packet collision. The delayed ACK and the ACK retransmission with priority in the case of packet collisions are analyzed and the effectiveness of the method is demonstrated. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(11): 99–107, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10134
A fundamental study of a thin λ/4 wave absorber using FSS technology
Authors: Itou Akihiko , Hashimoto Osamu , Yokokawa Hidehiro , Sumi Kazutoshi
Published: May 2004

The λ/4 wave absorber is expected to be useful for indoor wireless LAN because of its simple structure and ease of design. However, this type of wave absorber has the deficiency that the thickness cannot be less than 1/4 of the wavelength within the spacer used. In this paper, an FSS (Frequency Selective Surface) is inserted in tandem with a resistive film as an absorbing film in the spacer section of the λ/4 wave absorber. By varying the phase within the spacer, thickness reduction of the absorber is attempted. In this case, it is necessary to understand the impedance of the FSS at the design frequency. In this paper, the impedance is first derived by the FDTD method. Substituting this result into an electric equivalent circuit, the insertion position of the FSS and the surface resistivity of the resistive film maximizing the absorbing characteristic are determined. A thin λ/4 wave absorber of this type is designed and fabricated and the absorption is measured. It is confirmed that a λ/4 wave absorber can be realized with approximately half the conventional thickness. Basic data on the frequency characteristics and angular dependence of this type of absorber can be obtained. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(11): 77–86, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10180
Correspondence between frequency characteristics of radiated emission and input impedance of power‐ground planes of PCB
Authors: Fujiwara Osamu , Nakamura Kenji , Wang Jianqing
Published: May 2004

The frequency at the peak of electromagnetic radiation from a PCB (Printed Circuit Board) as a result of ground bounce is considered predictable from the frequency characteristics of the input impedance between the power supply and ground layer (below called the PCB impedance). However, the relationship is largely unknown. In this paper, the electromagnetic radiation of the PCB and the frequency spectrum of the PCB impedance are analyzed by the FDTD (Finite‐Difference Time‐Domain) method and their relational mechanism is studied by comparison with the measured values. It is found that the peak of the electromagnetic radiation appears at the frequency where the PCB is a minimum if the PCB is excited by a voltage source with an internal resistance sufficiently smaller than the PCB impedance, and that this peak is shifted toward the frequency at which the PCB impedance becomes a maximum if the internal resistance is increased. The radiation power ratio derived from the resistive components (called the resonant resistances) at two frequencies where the PCB impedance is maximum and minimum (resonant frequencies) mostly agrees with the ratio of the squares of the radiated electric field. Hence, the radiation peak frequencies of the PCB are determined both by the internal resistance of the excitation source and the resonant resistance of the PCB impedance. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(11): 30–38, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10209
Design method for a broadband inverted F antenna by parallel resonance mode
Authors: Sekine Syu‐ichi , Itoh Takayoshi , Odachi Noriaki , Murakami Yasushi , Shoki Hiroki
Published: May 2004

This paper presents a broadband inverted F antenna realized by adding a wire element and describes a method for its design based on the operating principle. This inverted F antenna has a configuration with a wire element attached at the middle of the wire element already connected at the feed point. Broadband operation is made possible by a new method in which a parallel resonance antenna is combined with the wire inverted F antenna, which is a series resonance antenna. A design method is proposed in which matching at each resonant frequency is independently adjusted by means of these two different resonances. Its effectiveness is demonstrated by experiments and by a simulation by NEC2. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(11): 11–20, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10215
De Novo Synthesis of Racemic Spirocyclopropane‐Annelated 2‐Deoxyhexose Derivatives
Authors: de Meijere Armin , Leonov Andrei , Heiner Thomas , Noltemeyer Mathias , Bes M. Teresa
Published: May 2004

High‐pressure‐induced inverse‐electron‐demand hetero‐Diels−Alder reactions of ethyl trans‐4‐ethoxy‐2‐oxo‐3‐butenoate (2a) and methyl trans‐4‐benzyloxy‐2‐oxo‐3‐butenoate (2b) with benzyl (cyclopropylidenemethyl) ether (1) each yielded mixtures of two separable diastereomeric esters 7a (64%) and 7b (80%) which, in three subsequent steps, led to the 3‐ethylated and 3‐benzylated α‐ and β‐anomeric benzyl spiro[2‐deoxy‐(D,L)‐arabino‐hexopyranoside‐2,1′‐cyclopropanes] α‐10a,b and β‐10a,b, respectively. The relative configuration of β‐10a was proved by an X‐ray crystal structure analysis. Deprotection of β‐10b was achieved by Pd‐catalyzed hydrogenation in dimethylacetamide leading to spiro[2‐deoxy‐α/β‐2‐(D,L)‐arabino‐hexopyranoside‐2,1′‐cyclopropane] (4). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
A Simple and Effective Procedure for the N‐Permethylation of Amino‐Substituted Naphthalenes
Authors: Sorokin Vladimir I. , Ozeryanskii Valery A. , Pozharskii Alexander F.
Published: May 2004

A wide range of amino‐substituted naphthalenes can be N‐permethylated by the system Me2SO4/Na2CO3/H2O(alcohols) with good to excellent yields. Steric hindrance does not prevent the reaction. Some amines with electron‐withdrawing groups, especially at nonconjugated positions, are also alkylated. The procedure allows the combination of a reduction (catalytic or by tin dichloride in acidic media) and a methylation in a one‐pot process. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Cover Picture: Eur. J. Org. Chem. 3/2003
Authors: Adam Waldemar , Diedering Manfred , Martí Vicente
Published: May 2004

The cover picture shows the spin‐dependent diastereoselectivities in the photodenitrogenation of a tricyclic azoalkane to the corresponding syn (inversion) and anti (retention) housanes. The saturated azoalkane A(CH2CH2) is the first example in which the triplet process is highly diastereoselective (see upper right‐hand corner). In this triplet 3DR(CH2CH2) diradical, steric effects between the gemdimethyl‐substituted methano bridge and the cyclopentane‐annellated ring are held responsible for the highly stereoselective ring closure to the anti‐housane. In the singlet photodenitrogenation the diazenyl diradical 1DZ(CH2CH2) intervenes, for which such steric effects are of minor relevance along the SH2 reaction coordinate (inversion). Details are discussed in the article by W. Adam, M. Diedering and V. Martí on p. 592 ff.
Microwave‐Assisted Solution‐Phase Synthesis of 1,4,5‐Trisubstituted Pyrazoles
Authors: Giacomelli Giampaolo , Porcheddu Andrea , Salaris Margherita , Taddei Maurizio
Published: May 2004

A small parallel library of 1,4,5‐trisubstituted pyrazoles was prepared in solution using a three‐step procedure starting from Meldrum acid. The Meldrum acid was acylated with different acyl chlorides and the products opened with different alcohols and amines to give substituted β‐keto esters and β‐keto amines. Further reaction with N,N‐dimethylformamide dimethylacetal and the final cyclisation were effectively carried out under microwave irradiation. Scavenger resins were employed exclusively in the first step, whereas use of microwaves allowed complete conversion of the starting materials in the other two steps. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Low Temperature, High Conversion, Liquid‐Phase Benzylic Oxidation with Dioxygen by Metal/NHPI‐Catalyzed Co‐Oxidation with Benzaldehyde
Authors: Schmieder‐van de Vondervoort Lizette , Bouttemy Sabine , Heu Ferdinand , Weissenböck Kurt , Alsters Paul L.
Published: May 2004

A new liquid‐phase catalytic oxidation system for the low temperature, high conversion benzylic mono‐oxyfunctionalization of 10,11‐dihydrocarbamazepine (1) into oxcarbazepine (4) with dioxygen has been developed. The method is based on a co‐oxidation of 1 with benzaldehyde in the presence of a four‐component catalyst system consisting of Co(OAc)2, Ni(OAc)2, Cr(NO3)3, and N‐hydroxyphthalimide (NHPI). The influence of the catalyst system on the formation and decomposition of the crucial hydroperoxide intermediate 2 has been investigated. Based on these results, the role of each of the components in the catalyst system is discussed. The scope of this method for the oxidation of other substrates has been studied, and the results are compared with those obtained by Co/NHPI catalyzed oxidation of these substrates. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)