bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct estimation of entropy loss due to reduced translational and rotational motions upon molecular binding
Authors: Lu Benzhuo , Wong Chung F. 
Published: August 2005

AbstractThe entropic cost due to the loss of translational and rotational (T–R) degree of freedom upon binding has been well recognized for several decades. Tightly bound ligands have higher entropic costs than loosely bound ligands. Quantifying the ligand's residual T–R motions after binding, however, is not an easy task. We describe an approach that uses a reduced Hessian matrix to estimate the contributions due to translational and rotational degrees of freedom to entropy change upon molecular binding. The calculations use a harmonic model for the bound state but only include the T–R degrees of freedom. This approximation significantly speeds up entropy calculations because only 6 × 6 matrices need to be treated, which makes it easier to be used in computer‐aided drug design for studying many ligands. The methodological connection with other methods is discussed as well. We tested this approximation by applying it to study the binding of ATP, peptide inhibitor (PKI), and several bound water molecules to protein kinase A (PKA). These ligands span a wide range in size. The model gave reasonable estimates of the residual T–R entropy of bound ligands or water molecules. The residual T–R entropy demonstrated a wide range of values, e.g., 4 to 16 cal/K·mol for the bound water molecules of PKA. © 2005 Wiley Periodicals, Inc. Biopolymers 79: 277–285, 2005This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
β‐Hairpin formation in aqueous solution and in the presence of trifluoroethanol: A 1H and 13C nuclear magnetic resonance conformational study of designed peptides
Authors: Santiveri Clara M. , Pantoja‐Uceda David , Rico Manuel , Jiménez M. Angeles 
Published: August 2005

AbstractIn order to check our current knowledge on the principles involved in β‐hairpin formation, we have modified the sequence of a 3:5 β‐hairpin forming peptide with two different purposes, first to increase the stability of the formed 3:5 β‐hairpin, and second to convert the 3:5 β‐hairpin into a 2:2 β‐hairpin. The conformational behavior of the designed peptides was investigated in aqueous solution and in 30% trifluoroethanol (TFE) by analysis of the following nuclear magnetic resonance (NMR) parameters: nuclear Overhauser effect (NOE) data, and CαH, 13Cα, and 13Cβ conformational shifts. From the differences in the ability to adopt β‐hairpin structures in these peptides, we have arrived to the following conclusions: (i) β‐Hairpin population increases with the statistical propensity of residues to occupy each turn position. (ii) The loop length, and in turn, the β‐hairpin type, can be modified as a function of the type of turn favored by the loop sequence. These two conclusions reinforce previous results about the importance of β‐turn sequence in β‐hairpin folding. (iii) Side‐chain packing on each face of the β‐sheet may play a major role in β‐hairpin stability; hence simplified analysis in terms of isolated pair interactions and intrinsic β‐sheet propensities is insufficient. (iv) Contributions to β‐hairpin stability of turn and strand sequences are not completely independent. (v) The burial of hydrophobic surface upon β‐hairpin formation that, in turn, depends on side‐chain packing also contributes to β‐hairpin stability. (vi) As previously observed, TFE stabilizes β‐hairpin structures, but the extent of the contribution of different factors to β‐hairpin formation is sometimes different in aqueous solution and in 30% TFE. © 2005 Wiley Periodicals, Inc. Biopolymers 79: 150–162, 2005This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
C2‐Symmetric Bis‐sulfoxides: Synthesis of Both Enantiomers and Utilization in Organometallic Chemistry and in Asymmetric Catalysis
Authors: Fernandez Inmaculada , Araujo Cristina S. , Alcudia Felipe , Khiar Noureddine 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Studies on Novel Synthetic. Part 56. Single‐Step Stereoselective Synthesis of (E)‐ and (Z)‐Allylamines from Acetyl Derivatives of Baylis—Hillman Adducts.
Authors: Das Biswanath , Mahender Gurram , Chowdhury Nikhil , Banerjee Joydeep 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Asymmetric Synthesis of α‐Monofluoromethyl‐ and α‐Difluoromethylbenzylamines Through Regioselective Hydrogenolysis.
Authors: Kanai Masatomi , Ueda Koji , Yasumoto Manabu , Kuriyama Yokusu , Inomiya Kenjin , Ootsuka Takashi , Katsuhara Yutaka , Higashiyama Kimio , Ishii Akihiro 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Controlling Diastereoselectivity in the Reactions of Enantiomerically Pure α‐Bromoacyl‐imidazolidinones with Nitrogen Nucleophiles: Substitution Reactions with Retentions or Inversion of Configuration.
Authors: Treweeke N. R. , Hitchcock P. B. , Pardoe D. A. , Caddick S. 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Remote Asymmetric Induction by Sulfoxides: DIBAL Reduction and Et2AlCN Hydrocyanation of ortho‐(p‐Tolylsulfinyl)benzyl Ketones
Authors: Garcia Ruano Jose L. , Rodriguez‐Fernandez M. Mercedes , Fernandez‐Ibanez M. Angeles , Maestro M. Carmen 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Unexpectedly Superior Enantioselectivity for trans‐Stilbene cis‐Dihydroxylation over Anchored Triosmium Carbonyl Species in Confined Al‐MCM‐41 Channels.
Authors: Caps Valerie , Paraskevas Ioannis , Tsang Shik Chi 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Coupling of 1‐Alkyl‐2‐(bromomethyl)aziridines with Lithium Dialkylcuprates Towards 1,2‐Dialkylaziridines.
Authors: D'hooghe Matthias , Rottiers Mario , Jolie Robrecht , De Kimpe Norbert 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Regioselective Synthesis, Structure and Behavior in Solutions of Novel Phosphorylated Thiazolidin‐4‐ones.
Authors: Kozlov Vladimir A. , Odinets Irina L. , Lyssenko Konstantin A. , Churusova Svetlana G. , Yarovenko Sergey V. , Petrovskii Pavel V. , Mastryukova Tatyana A. 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Structural Modifications and Antimicrobial Activity of N‐Cycloalkenyl‐2‐acylalkylidene‐2,3‐dihydro‐1,3‐benzothiazoles.
Authors: Latrofa Andrea , Franco Massimo , Lopedota Angela , Rosato Antonio , Carone Dora , Vitali Cesare 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Stereoselective Synthesis of Trisubstituted Tetrahydropyrans from Baylis—Hillman Derivatives via n‐Bu3SnH‐Mediated 6‐endo/6‐exo‐trig Vinyl Radical Cyclization.
Authors: Shanmugam Ponnusamy , Rajasingh Paramasivan 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Alkylation of 3‐Cyano‐4‐methoxymethyl‐6‐methyl‐2(1H)‐pyridone by Active Halomethylene Compounds. The Molecular Structure of 3‐Amino‐2‐benzoyl‐4‐methoxymethyl‐6‐methylfuro[2,3‐b]pyridine.
Authors: Kaigorodova E. A. , Vasilin V. K. , Sidorova E. A. , Zavodnik V. E. , Krapivin G. D. 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Catalytic Enantioselective Conjugate Addition of Dialkylzinc Reagents to N‐Substituted‐2,3‐dehydro‐4‐piperidones.
Authors: Sebesta Radovan , Pizzuti Maria Gabriella , Boersma Arnold J. , Minnaard Adriaan J. , Feringa Ben L. 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Pyridazine Derivatives. Part 40. Reactivity of 5‐Alkynylpyridazin‐3(2H)‐ones Toward Hydrochloric Acid.
Authors: Coelho Alberto , Novoa Hector , Peeters Oswald M. , Blaton Norbert , Alvarado Mario , Sotelo Eddy 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis and Antiproliferative Activity in vitro of New 2‐Aminobenzimidazole Derivatives. Part 2.
Authors: Nawrocka W. , Sztuba B. , Liszkiewicz H. , Kowalska M. W. , Wietrzyk J. , Nevozhai D. , Opolski A. 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Unexpected Reaction of 3‐Benzoyl‐4‐hydroxy‐2‐methyl‐4‐phenylpiperidine with 1,2‐Diaminobenzene.
Authors: Soldatenkov A. T. , Kutyakov S. V. , Volkov S. V. , Mamyrbekova Zh. A. , Polyanski K. B. 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Microwave‐Assisted Cyclocondensation of Dialdehydes with Chiral Diamines Forming Calixsalen Type Macrocycles.
Authors: Srimurugan Sankareswaran , Viswanathan Balasubramanian , Varadarajan Thirukkallam Kanthadai , Varghese Babu 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of Non‐Natural Amino Acids Based on the Ruthenium‐Catalyzed Oxidation of a Phenyl Group to Carboxylic Acid.
Authors: Moutevelis‐Minakakis Panagiota , Sinanoglou Charalambos , Loukas Vassilios , Kokotos George 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Benzoyl Cyanide: A Mild and Efficient Reagent for Benzoylation of Nucleosides.
Authors: Prasad Ashok K. , Kumar Vineet , Maity Jyotirmoy , Wang Zhiwei , Ravikumar Vasulinga T. , Sanghvi Yogesh S. , Parmar Virinder S. 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of Novel Non‐Isoprenoid Phenolic Acids and 3‐Alkylpyridines
Authors: Jain Subhash C. , Kumar Rohtash , Goswami Rajeev , Pandey Mukesh K. , Khurana Shilpi , Rohatgi Leena , Gyanda Kapil 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Noniterative Approach to the Total Asymmetric Synthesis of 15‐Carbon Polyketides and Analogues with High Stereodiversity
Authors: Vogel Pierre , Gerber‐Lemaire Gerber , Carmona Ana T. , Meilert Kai Torsten , Schwenter Marc‐Etienne 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
Approaches to the Stereoselective Total Synthesis of Biologically Active Natural Products
Authors: Baron Anne , Ball Matthew , Bradshaw Benjamin , Donnelly Sam , Germany Olivier , Oller Pilar C. , Kumar Naresh , Martin Nathaniel , O'Brien Matthew , Omori Hiroki , et al. et al. 
Published: August 2005

AbstractFor Abstract see ChemInform Abstract in Full Text.
First Observation of NIR 4f–4f Luminescence through the Energy Transfer from the SOMO π* Doublet in Nitronyl Nitroxide Radical Lanthanide(III) Complexes
Authors: Kaizaki Sumio , Shirotani Dai , Tsukahara Yasunori , Nakata Hiroyasu 
Published: August 2005

AbstractThis study demonstrates the first observation of energy transfer from the doublet state of the nitronyl nitroxide radical ligand in LnIII complexes, exerting the light‐harvesting antenna effect on the NIR luminescence for the first time. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
The N‐Lithiation of 2,4,6‐Triphenylborazine
Authors: Nöth Heinrich , Troll Alexander 
Published: August 2005

AbstractThe reaction of the borazine Ph3B3N3H3, 1, with a diethyl ether solution of LiMe/LiI/TMEDA yields [(Ph4B3N3H3)Li(tmeda)LiI(tmeda)], 2. However, when halide free LiMe is used in the presence of TMTA, then (Ph4B3N3H3)Li(tmta), 3, is formed which shows that a Me/Ph exchange occurs with the formation of LiPh which adds to 1 to form the borazinate 3. A Bu/Ph exchange is also observed in the reaction of 1 with LitBu/tmta. The product isolated from THF is compound [(Ph4B3N3H2Li–Li(thf)3], 6c, which results from deprotonation of and LiPh addition to 1. A straightforward 1:1 LiPh addition reaction is observed on treatment of the borazine Ph3B3N3Me3, 4, with LiPh in diethyl ether solution to give the borazinate (Ph4B3N3Me3)Li(OEt2), 5. Reaction of 1 with LiPh (ratio 1:1) in diethylether produces (Ph4B3N3H2Li)[Ph3B3N3H2Li(OEt2)2], 7, while an excess of LiPh leads to triple deprotonation and LiPh addition to the N atoms of compound (Ph3B3N3Li3) to give the adduct [Ph3B3N3Li3(OEt2)3][LiPh(OEt2)], 8. All new compounds have been characterized by spectroscopic methods and X‐ray structure determinations. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Current‐Voltage Characterisation of Monolayer‐Supported Au‐Nanoclusters by Scanning Tunnelling Microscopy under Ambient Conditions
Authors: Jacobsen Volker , Zhu Tao , Knoll Wolfgang , Kreiter Maximilian 
Published: August 2005

AbstractThe current‐voltage characteristics of a double‐tunnel junction based on a gold crystallite with a diameter of ca. 2 nm, separated from a gold surface by ca. 1 nm was investigated by scanning tunnelling microscopy. The sample architecture was built by attaching gold nanoparticles covered with 2‐mercaptosuccinic acid to an atomically flat gold surface which was covered by a self‐assembled monolayer (SAM) of 6‐amino‐1‐hexanethiol. Surface plasmon and infrared spectroscopy as well as STM imaging were employed to identify suitable preparation conditions and prove the existence of the desired architecture. No reproducible steps in the current‐voltage characteristics are observed on this system under ambient conditions. Nonetheless, a sound signature for tunnelling through the double‐tunnel junction is established by a quantitative fit of the averaged experimental data to a theoretical model of a single‐tunnel junction. Firstly, the current on the particle is strongly reduced at low absolute external voltage and secondly the current voltage characteristics are asymmetric. Since both deviations from theory are absent in reference experiments on the bare monolayer, they may serve as a robust signature for double‐tunnel junctions and open the door to the investigation of single‐electron tunnelling under ambient conditions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
The Effects of Organisation, Embedding and Surfactants on the Properties of Cadmium Chalcogenide (CdS, CdSe and CdS/CdSe) Semiconductor Nanoparticles
Authors: Frenzel Johannes , Joswig Jan‐Ole , Sarkar Pranab , Seifert Gotthard , Springborg Michael 
Published: August 2005

AbstractAn overview of recent density‐functional‐based studies on the structure, surface structure and electronic and optical properties of CdS, CdSe and CdS/CdSe semiconductor nanoparticles is given. In particular, the effects of organisation, embedding and surfactants on the properties of these particles are discussed and illustrated by our own results and literature examples. The surface stabilisation by ligands, core/shell embedding or superstructure organisation combined with electronic structure stabilisation of these nanoparticles directly influences their properties: for stabilised nanoparticles a size‐dependent decay of the lowest optical excitation energy towards the value of the bulk is found, as observed experimentally. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Regional econometric income forecast accuracy
Authors: Fullerton Thomas M. , Tinajero Roberto , Waldman Lawrence 
Published: August 2005

AbstractEconometric prediction accuracy for personal income forecasts is examined for a region of the United States. Previously published regional structural equation model (RSEM) forecasts exist ex ante for the state of New Mexico and its three largest metropolitan statistical areas: Albuquerque, Las Cruces and Santa Fe. Quarterly data between 1983 and 2000 are utilized at the state level. For Albuquerque, annual data from 1983 through 1999 are used. For Las Cruces and Santa Fe, annual data from 1990 through 1999 are employed. Univariate time series, vector autoregressions and random walks are used as the comparison criteria against structural equation simulations. Results indicate that ex ante RSEM forecasts achieved higher accuracy than those simulations associated with univariate ARIMA and random walk benchmarks for the state of New Mexico. The track records of the structural econometric models for Albuquerque, Las Cruces and Santa Fe are less impressive. In some cases, VAR benchmarks prove more reliable than RSEM income forecasts. In other cases, the RSEM forecasts are less accurate than random walk alternatives. Copyright © 2005 John Wiley & Sons, Ltd.
Sediment infiltration traps: their use to monitor salmonid spawning habitat in headwater tributaries of the Cascapédia River, Québec
Authors: Zimmermann André E. , Lapointe Michel 
Published: August 2005

AbstractSediment infiltration can clog salmon nests and reduce egg survival. As a countermeasure, environmental managers often deploy infiltration traps to monitor sediment infiltration. Traps provide a repeatable means of measuring infiltration and enable comparisons to be made between sites. Results from infiltration rates measured with traps have also been used to estimate infilling rates into salmon nests. Application of these data is questionable, as the composition of the bed and the amount of fine sediment within the bed is known to affect infiltration rates. Thus, infiltration rates measured with infiltration traps may differ from the infiltration rates occurring in redd and riffle gravels.To examine how relationships between sediment infiltration rates varied between four watersheds, we continuously monitored suspended sediment transport, shear stress and infiltration rates at four sites over 5 months. We also compared infiltration rates measured with infiltration traps with changes in the hydraulic conductivity and subsurface grain size distribution of adjacent artificially constructed salmon nests and natural riffle gravels.Among the four watersheds, clear differences in sediment infiltration rates were observed. The differences correlated with the subsurface silt content but no strong relationship existed between land‐use or basin physiography/geology. Despite observing an average of 30 kg m−2 of sediment finer than 2 mm being deposited in the infiltration traps during the study, no change in redd or riffle substrate was observed. If the deposition rates measured with the traps reflect the processes in redds, enough sediment would have been deposited to inhibit egg emergence. However, no reduction in egg survival to the eyed stage was observed. In summary, our results show that infiltration traps with clean gravels can be used to detect intersite differences in sediment transport regimes. Extrapolations of sediment infiltration rates measured with such collectors to estimate infiltration rates in redds or riffles is, however, flawed. Copyright © 2005 John Wiley & Sons, Ltd.
Analysis of the epidermal growth factor receptor specific transcriptome: Effect of receptor expression level and an activating mutation
Authors: Pedersen Mikkel W. , Pedersen Nina , Damstrup Lars , Villingshøj Mette , Sønder Søren U. , Rieneck Klaus , Bovin Lone F. , Spang‐Thomsen Mogens , Poulsen Hans S. 
Published: August 2005

AbstractOverexpression or expression of activating mutations of the epidermal growth factor receptor (EGFR) is common in cancer and correlates with neoplastic progression. The present study employed Affymetrix® oligonucleotide arrays to profile genes induced by ligand‐activated EGFR with the receptor either moderately expressed or overexpressed at an in‐itself transforming level. These changes were compared to those induced by the naturally occurring constitutively active variant EGFRvIII. This study provides novel insight on the activities and mechanisms of EGFRvIII and EGFR mediated transformation, as genes encoding proteins with functions in promoting cell proliferation, invasion, antiapoptosis, and angiogenesis featured prominently in the EGFRvIII‐ and EGFR‐expressing cells. Surprisingly, it was found that ligand‐activated EGFR induced the expression of a large group of genes known to be inducible by interferons. Expression of this module was absent in the EGFRvIII‐expressing cell line and the parental cell line. Treatment with the specific EGFR inhibitor AG1478 indicated that the regulations were primary, receptor‐mediated events. Furthermore, activation of this module correlated with activation of STAT1 and STAT3. The results thus demonstrate that ligand‐activated EGFR at different expression levels results in different kinetics of signaling and induction of gene expression. In addition, the constitutively active variant EGFRvIII seems to activate only a subset of signal pathways and induce a subset of genes as compared to the ligand‐activated EGFR. © 2005 Wiley‐Liss, Inc.
Statins in nephrotic syndrome: A new weapon against tissue injury
Authors: Buemi Michele , Nostro Lorena , Crascì Eleonora , Barillà Antonio , Cosentini Vincenzo , Aloisi Carmela , Sofi Tito , Campo Susanna , Frisina Nicola 
Published: August 2005

AbstractThe nephrotic syndrome is characterized by metabolic disorders leading to an increase in circulating lipoproteins levels. Hypertriglyceridemia and hypercholesterolemia in this case may depend on a reduction in triglyceride‐rich lipoproteins catabolism and on an increase in hepatic synthesis of Apo B‐containing lipoproteins. These alterations are the starting point of a self‐maintaining mechanism, which can accelerate the progression of chronic renal failure. Indeed, hyperlipidemia can affect renal function, increase proteinuria and speed glomerulosclerosis, thus determining a higher risk of progression to dialysis. 3‐hydroxy‐3‐methylglutaryl‐coenzyme A (HMG‐CoA) reductase is the rate‐limiting enzyme in cholesterol synthesis from mevalonate and its inhibitors, or statins, can therefore interfere with the above‐mentioned consequences of hyperlipidemia. Statins are already well known for their effectiveness on primary cardiovascular prevention, which cannot be explained only through their hypolipemic effect. As far as kidney diseases are concerned, statin therapy has been shown to prevent creatinine clearance decline and to slow renal function loss, particularly in case of proteinuria, and its favorable effect may depend only partially on the attenuation of hyperlipidemia. Statins may therefore confer tissue protection through lipid‐independent mechanisms, which can be triggered by other mediators, such as angiotensin receptor blockers. Possible pathways for the protective action of statins, other than any hypocholesterolemic effect, are: cellular apoptosis/proliferation balance, inflammatory cytokines production, and signal transduction regulation. Statins also play a role in the regulation of the inflammatory and immune response, coagulation process, bone turnover, neovascularization, vascular tone, and arterial pressure. In this study, we would like to provide scientific evidences for the pleiotropic effects of statins, which could be the starting point for the development of new therapeutical strategies in different clinical areas. © 2005 Wiley Periodicals, Inc.