bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation of Polynuclear (Diamine)telluratocobalt(III) Complexes
Authors: Hosokawa Yutaka , Shimura Yoichi 
Published: July 2006

Abstract
Penta- and hexa-nuclear condensates of mono(diamine)cobalt(III) complexes and tellurates have been prepared and some of the optically active isomers separated. They are [{Co(TeO6H4)(diamine)}(Te2O10){Co(TeO6H4)(diamine)}]6− (brown complexes) and [{Co(TeO6H4)(diamine)}(TeO6){Co(TeO6H4)(diamine)}]4− (blue complexes), where diamine=ethylenediamine, (R)-(−)-propylenediamine, and (R,R)-(−)-1,2-cyclohexanediamine. The structures have been determined from the visible and ultraviolet absorption and circular dichroism spectra; the electrostatic repulsion between cobalt(III) and tellurium (VI) atoms is considered in detail.
Synthesis and Characterization of Cobalt(II), Nickel(II), and Copper(II) Complexes with 2-Furancarbaldehyde Oxime
Authors: Kuma Hiro , Motobe Kyoji , Mori Wasuke , Yamada Shoichiro 
Published: July 2006

Abstract
Cobalt(II), nickel(II), and copper(II) complexes with 2-furancarbaldehyde oxime have been prepared and characterized mainly on the basis of electronic spectra and magnetic data. The cobalt(II) and nickel(II) complexes of the formula MX2(oxime)4 (X=Cl, Br) have been isolated. They are all six-coordinated, the oxime being coordinated as a unidentate through the nitrogen atom. Copper(II) forms complexes of the formula CuX2(oxime)2 (X=Cl, Br). Possible structures for these complexes are discussed.
The Total Synthesis of Neomycin C
Authors: Umezawa Sumio , Harayama Akihiko , Nishimura Yoshio 
Published: July 2006

Abstract
The total synthesis of the pseudo-tetrasaccharides antibiotic neomycin C is described, involving condensation of 6,3′,4′,5″-tetra-O-acetyl-1,3,2′,6′-tetra-N-(benzyloxycarbonyl)ribostamycin with 3,4-di-O-acetyl-2-deoxy-2-(p-methoxybenzylideneamino)-6-O-tosyl-α-d-glucopyranosyl bromide by a modified Koenigs-Knorr reaction.
Reaction of Dialkyl-substituted Alkynes with Carbon Dioxide Catalyzed by Nickel(0) Complexes. Incorporation of Carbon Dioxide in Alkyne Dimers and Novel Cyclotrimerization of the Alkynes
Authors: Inoue Yoshio , Itoh Yoshio , Kazama Haruo , Hashimoto Harukichi 
Published: July 2006

Abstract
Ni(cod)2–Ph2P(CH2)4PPh2 system (cod=1,5-cyclooctadiene) catalyzed the reaction of 3-hexyne, for example, with CO2 to give a CO2 incorporated product, i.e., tetraethyl-2-pyrone, in a fairly good yield together with novel two cyclotrimers of the alkyne having cyclopentadiene structures, i.e., pentaethyl-5-(1-propenyl)-1,3-cyclopentadiene and pentaethyl-5-allyl-1,3-cyclopentadiene. The novel two cyclotrimers were formed selectively on Ni(cod)2–PPh3 system under CO2, whereas under N2 the main trimer was hexaethylbenzene. A nickelacyclopentadiene intermediate has been proposed for the pyrone formation. The novel two cyclotrimers were also formed on the oligomerization catalyzed by a cationic nickel hydride complex, [HNi(Ph2PCH2CH2PPh2)2]OCOCF3, together with a novel dimer having a methylenecyclobutene structure, i.e., 1,2,4-triethyl-3-ethylidenecyclobutene. The effect of phosphine added and that of active-hydrogen compounds on the novel oligomerization are mentioned.
Carbon-13 NMR Chemical Shifts of Some Ruthenocenophanes and Ferrocenophanes
Authors: Senda Yasuhisa , Kamiyama Shin-ichi , Kasahara Akira , Izumi Taeko , Murakami Satoshi 
Published: July 2006

Abstract
The 13C NMR spectra of ruthenocenophanes, ferrocenophanes and their precursors were measured. The examination of molecular models for metallocenophanes and the spectral data offer some hints about the conformation of the molecules.
Synthetic Studies on Terpenic Compounds. XII. Selective Degradation of the Side Chain in Portulal
Authors: Tokoroyama Takashi , Matsuo Keizo , Kanazawa Reizo 
Published: July 2006

Abstract
Stepwise degradation of the side chain in portulal has been investigated in connection with synthetic studies. Selective cleavage of the double bond in the side chain was achieved by ozonolysis after protection of the endo-double bond by iodoetherification of the corresponding alcohol. Further degradation led to the formation of the γ-lactone via the δ-lactone.
Fluorescence Decay Studies of 9-Aminoacridine Bound to Polyriboadenylic Acid
Authors: Kubota Yukio , Motoda Yuko 
Published: July 2006

Abstract
The interaction of the mutagenic dye 9-aminoacridine (9AA) with polyriboadenylic acid (poly rA) was studied by both steady-state and transient fluorescence measurements. It was found that the fluorescence decay of 9AA bound to poly d(A-T) follows a single-exponential decay law but that the decay data of 9AA bound to poly rA can be well described as a sum of two-exponential functions. The fact that nanosecond time-resolved fluorescence spectra are independent of time suggests that the double-exponential decay may be attributed to different microenvironments at the binding sites. The decay parameters, fluorescence emission maxima, and fluorescence quantum yields obtained at acid pH differ from those obtained at neutral pH. The fluorescence behavior of 9AA is discussed in connection with the conformational change of poly rA.
Is O2*(a1Δg) Formed in the O+O3, H+O3, and NO+O3 Reactions ?
Authors: Washida Nobuaki , Akimoto Hajime , Okuda Michio 
Published: July 2006

Abstract
An attempt was made to detect O2*(a1Δg) in the reactions of O+O3, H+O3, and NO+O3 using a photoionization mass spectrometer. No significant signals for O2*(a1Δg) were observed in these reactions. From the results, it is concluded that less than 0.06, 0.001, and 0.002 of the reactive collisions result in the production of O2*(a1Δg) in the reactions of O+O3, H+O3, and NO+O3 respectively, all at 298 K. The failure to observed O2*(a1Δg) in these reactions was discussed by means of correlation diagrams and GVB model representations.
Paramagnetic Cobalt(III) Complexes with Organic Ligands. V. The Isolation and Properties of Salts of the Paramagnetic Bis(2,2′-bipyridine)(5-nitrosalicylato)cobalt(III) and of the Paramagnetic “β1 and β2”-Isomers of the 5-Nitrosalicylato(triethylenetetramine)cobalt(III) and Their Derivatives
Authors: Yamamoto Yoshihisa , Toyota Eiko , Mitsudera Naoto 
Published: July 2006

Abstract
The picrate of the paramagnetic, [Co(5-NO2sal)(bpy)2]2+, has been isolated from a reaction mixture of picric acid, 60% nitric acid, and bis(2,2′-bipyridine)(salicylato)cobalt(III) chloride trihydrate, [Co(sal)(bpy)2]Cl·3H2O, which had been prepared from salicylic acid and cis-bis(2,2′-bipyridine)dichlorocobalt(III) chloride dihydrate. The absorption spectrum and the stability of an aqueous solution of the picrate of the paramagnetic, [Co(5-NO2sal)(bpy)2]2+, were somewhat different from those of complexes of the paramagnetic, [Co(5-NO2sal-R)(NH3)4]2+ (R: H, CH3). Several complexes of the paramagnetic, β1-5-nitrosalicylato-, β2-5-nitrosalicylato-, and β2-3-methyl (and 4-methyl)-5-nitrosalicylato(triethylenetetramine)cobalt(III) have, analogously, been isolated from reaction mixtures of 60% nitric acid and β1-salicylato-, β2-salicylato, or β2-methylsalicylato(triethylenetetramine)cobalt(III) chloride hydrate respectively. Their β1 and β2-isomeric forms were proved by a study of their IR and 1H-NMR spectra. From the IR, NMR, and the magnetic susceptibility measurement results, these compounds are considered to have the paramagnetic complex, [Co(5-NO2sal)L]2+(L: (NH3)4, (en)2, (bpy)2, and trien), and the electron hole is considered to delocalize over the chelate ring containing the cobalt atom and the 5-nitrosalicylato ligand.
Polarographic Study on the Transportation of Oxygen by Perfluorocarbon Emulsion as Artificial Blood
Authors: Hayashi Katsumi , Takagi Masanosuke 
Published: July 2006

Abstract
Restrictive factors of oxygen release from dispersed particles of perfluorocarbon (PFC) in a form of emulsion have been studied by polarographic reduction currents of oxygen in the emulsion. The oxygen reduction currents in PFC emulsion in open system increased linearly with the volume fraction of PFC component, and were diffusion-controlled. The increase of current was ascribed to the increase of oxygen supply to the electrode from PFC particles in the emulsion. Analyzing the oxygen reduction current due to PFC particles, the ratio of diffusion coefficients of oxygen inside and outside PFC particle (D1⁄D0) and the oxygen partition coefficient between the both sides (C1⁄C0) were obtained. The release of oxygen from PFC particle was rate-determined by oxygen diffusion in the particle and the diffusion itself was determined by inner viscosity of PFC particle. The surfactant layer of PFC particle did not play any appreciable role such as permeability barrier for oxygen transportation.
Potentiometric Study on the Complex Formation of Cobalt(II) Ion with Ethylenediamine-N-acetic Acid, Diethylenetriamine, and Iminodiacetic Acid
Authors: Ohsaka Takeo , Oyama Noboru , Matsuda Hiroaki 
Published: July 2006

Abstract
The formation constants of Co(II)–ethylenediamine-N-acetate (edma), –diethylenetriamine (dien) and –iminodiacetate (ida) complexes were determined by potentiometric titration in 1.0 M NaClO4 solution at 25 °C. The following results were obtained. Edma: logβ101=7.51, logβ102=14.05: dien: logβ101=9.34, logβ102=16.89; ida: logβ101=6.54, logβ102=11.95, βpqr being the overall formation constant defined in the text. The relative effects of amino and carboxyl groups on the affinity of ligands to Co(II) ion are discussed.
Lithiation of Alkoxyalkyl Phenyl Sulfones. New Approach to Acyl Anion Synthesis
Authors: Tanaka Kazuhiko , Matsui Syuichi , Kaji Aritsune 
Published: July 2006

Abstract
(1-Ethoxyethoxy)methyl and 1-(1-ethoxyethoxy)ethyl phenyl sulfones undergo metalation with LDA in THF in the presence of HMPA. The resulting lithium salts were easily alkylated with various alkyl halides and hydrolyzed under mild conditions to give the corresponding carbonyl compounds. The new synthetic method for the preparation of aldehydes and ketones employing these carbanions has been developed.
A Catalytic Effect of Amines on the Reaction of Arenesulfinic Acids with N,N′-Thiodiphthalimide
Authors: Abe Yasuo , Horii Toyokazu , Oka Kunio , Kawamura Shunichi , Nakabayashi Takeshige 
Published: July 2006

Abstract
In the presence of catalytic amounts of several amines, N,N′-thiodiphthalimide has been allowed to react with one or two equiv. of arenesulfinic acids in dichloromethane, thus giving N-(arylsulfonylthio)phthalimides or bis(arenesulfonyl) sulfides respectively in good yields. The arenesulfinate anion seems to be a better nucleophile against N,N′-thiodiphthalimide than arenesulfinic acid. The mechanism of the catalytic reaction will be discussed.
The Acetylation of Toluene and Benzene with Acetyl Chloride and Bromide and Acetic Anhydride Catalyzed by Calcined Iron Sulfate Activated by Exposure to a Mixture of Benzyl Chloride and the Aromatics
Authors: Arata Kazushi , Hino Makoto 
Published: July 2006

Abstract
The acetylations of toluene and benzene with acetyl halides and acetic anhydride were studied over catalysts prepared by heat-treating FeSO4 in air, followed by activation on exposure to benzyl chloride in toluene or benzene at 40–80 °C for 1 h, together with FeCl3 and AlCl3. The sulfates treated at 700 and 800 °C showed high activity. The former, activated at 60 °C, gave 68% methylacetophenones, and the latter, more than 90%, with an isomer distribution of 2% ortho-, 1% meta-, and 97% para-form in the reaction of toluene with acetyl halides at room temperature, while the maximum yield was 24% with FeCl3 and 29% with AlCl3. A high yield of acetophenone, 77%, was obtained over the FeSO4 (700 °C) catalyst in the reaction of benzene with acetyl bromide at 60 °C for 1 h. The present catalysts were also highly active for the acetylation of toluene with acetic anhydride; e.g., 55% methylacetophenones were obtained over the FeSO4 (800 °C) catalyst at 100 °C for 5 h. FeCl3 and AlCl3 gave quite low yield compared with the present catalysts.
The Crystal Structure of N-(t-Butoxycarbonyl)-l-methionylglycine Benzyl Ester
Authors: Yamane Takashi , Umemura Takashi , Kojima Tadao , Yamada Yasuyuki , Ashida Tamaichi 
Published: July 2006

Abstract
The crystal structure of N-(t-butoxycarbonyl)-l-methionylglycine benzyl ester has been determined. The crystal data are: P21, a=15.884(4), b=5.083(2), c=13.296(3) Å, β=94.54(2)°, Z=2. The final R is 0.055 for 1518 reflections. In the methionyl residue the Cα–Cβ bond is longer than the Cβ–Cγ bond. The tendency is consistent with that found in the other methionine compounds. The methionyl side chain has the most stable trans zig-zag conformation (χ1=−73.2, χ2=175.3, and χ3=174.9°). The peptide main chains are packed in a parallel β-sheet structure, the torsion angles (φ,ψ) of the methionyl residue being (−110.6, 108.3°).
Liquid Crystal Formation in Binary Systems. I. An Interpretation of the Phase Diagrams of the Azoxydianisole–Schiff Base Systems
Authors: Araya Kotaro , Matsunaga Yoshio 
Published: July 2006

Abstract
In order to confirm the presence of a transition at the temperature where the liquid crystal-isotropic liquid transition curve in the nematogen-rich region is met by the other transition curve, five binary systems comprising azoxydianisole (AA) and a Schiff base were examined by means of differential scanning calorimetry. A small but sharp endothermic peak due to a phase change is observable at the expected temperature upon heating, provided that it is well separated from the eutectic temperature. When the above-mentioned curve intersects the solid-liquid transition curve on the Schiff base-rich side, a liquid crystal coexisting with the solid base is transformed into an isotropic liquid coexisting with the same solid at this temperature. The presence of a nematic phase below this temperature could be demonstrated by measuring the separation of the outer hyperfine extrema in the ESR spectrum of bis(acetylacetonato)oxovanadium(IV) dissolved in the mixtures. The sequence of the transformation is entirely different when the intersection occurs on the AA-rich side. However, attempts to confirm the transition of the latter type by ESR were not successful.
Solubilization of Coal by a Treatment with Butylzinc Compounds under Mild Conditions. —Active Species in a Zinc-Butyl Iodide System for Coal Solubilization—
Authors: Yoneyama Yoshiharu , Kato Tsutomu , Mizutani Makoto , Gonda Kiyoshi 
Published: July 2006

Abstract
To elucidate the effectiveness of a treatment of coal with butylzinc compounds on coal solubilization, Yubari coal was treated with Bu2Zn and/or BuZnX (X = Cl, Br, I) in the presence or absence of alkyl halide (RX). Both the treatment using Bu2Zn or BuZnI and that with a combination of Bu2Zn and RX (X = Cl, Br) were not very effective for coal solubilization, whereas the combination of Bu2Zn, BuZnX (X = Cl, Br, I) and BuX (X = Cl, Br, I) was very effective. The best yield of a benzene-soluble product (BS) of Yubari coal was 96%. The 13C NMR and FT-IR spectra of each BS fraction of Yubari coal treated with 13CH3I, CH3I, and BuI, respectively, in the presence of BuZnI and Bu2Zn showed that the alkyl and butyl groups from RX and butylzinc compounds were introduced into the BS fractions according to addition and substitution toward aromatic moieties. The addition of alkyl groups to aromatic moieties seemed to be more effective coal solubilization than the substitution of alkyl groups. These results indicate that BuZnI, Bu2Zn, and BuI are indispensable species in the Zn/BuI system for effective coal-solubilization.
Selective Hydrogenation of Alkynes Catalyzed by Metallic Nickel and Modifier
Authors: Sakai Mutsuji , Takai Yoshihiro , Mochizuki Hiroki , Sasaki Ken , Sakakibara Yasumasa 
Published: July 2006

Abstract
Under an atmospheric pressure of hydrogen alkynes were successively hydrogenated to give alkanes via (Z)-alkenes with the metallic nickel catalyst, which was easily prepared by reaction of nickel bromide with zinc powder. Phosphines and diamines as catalyst modifiers were effective for the partial hydrogenation of alkynes.
Application of a chronic illness model as a means of understanding pre‐operative psychological adjustment in coronary artery bypass graft patients
Authors: Oxlad Melissa , Wade Tracey D. 
Published: July 2006

Objectives. To increase understanding of the factors associated with pre‐operative psychological adjustment in coronary artery bypass graft (CABG) patients by assessing the utility of a chronic illness model developed by Scharloo, Kaptein, Weinman, Willems, and Rooijmans (2000).Design. A cross‐sectional design was employed.Method. Elective CABG patients (N = 119) completed self‐report measures of illness representation, self‐rated health, social support, coping methods, and pre‐operative adjustment (depression and post‐traumatic stress disorder (PTSD) symptomatology) an average of 30 days prior to surgery. Hierarchical multiple regression was used to assess the mediational relationships proposed by the chronic illness model.Results. Five 3‐variable mediational chains were assessed. In all instances, the results conformed to the relationships suggested by the chronic illness model where the strength of the relationship between the independent and dependent variables was reduced when the mediator variable was controlled. However, a significant reduction of this relationship was found in three of the five chains examined. The most rigorous support for the model occurred, where increased use of avoidance coping mediated the relationship between poorer self‐rated health and increased PTSD symptomatology, and also where increased use of avoidance coping partially mediated the relationship between a more negative illness representation and increased PTSD symptomatology, and poorer self‐rated health and increased depression.Conclusions. The chronic illness model of Scharloo and colleagues shows potential in explaining pre‐operative adjustment in CABG patients. Longitudinal examination of the model is recommended.
A validity and reliability study of the coping self‐efficacy scale
Authors: Chesney Margaret A. , Neilands Torsten B. , Chambers Donald B. , Taylor Jonelle M. , Folkman Susan 
Published: July 2006

Objectives. Investigate the psychometric characteristics of the coping self‐efficacy (CSE) scale, a 26‐item measure of one's confidence in performing coping behaviors when faced with life challenges.Design. Data came from two randomized clinical trials (N1 = 149, N2 = 199) evaluating a theory‐based Coping Effectiveness Training (CET) intervention in reducing psychological distress and increasing positive mood in persons coping with chronic illness.Methods. The 348 participants were HIV‐seropositive men with depressed mood who have sex with men. Participants were randomly assigned to intervention and comparison conditions and assessed pre‐ and post‐intervention. Outcome variables included the CSE scale, ways of coping, and measures of social support and psychological distress and well‐being.Results. Exploratory (EFA) and confirmatory factor analyses (CFA) revealed a 13‐item reduced form of the CSE scale with three factors: Use problem‐focused coping (6 items, α = .91), stop unpleasant emotions and thoughts (4 items, α = .91), and get support from friends and family (3 items, α = .80). Internal consistency and test–retest reliability are strong for all three factors. Concurrent validity analyses showed these factors assess self‐efficacy for different types of coping. Predictive validity analyses showed that residualized change scores in using problem‐ and emotion‐focused coping skills were predictive of reduced psychological distress and increased psychological well‐being over time.Conclusions. The CSE scale provides a measure of a person's perceived ability to cope effectively with life challenges, as well as a way to assess changes in CSE over time in intervention research.
Connective Tissue Growth Factor in Serum as a New Candidate Test for Assessment of Hepatic Fibrosis
Authors: Gressner Axel M , Yagmur Eray , Lahme Birgit , Gressner Olav , Stanzel Sven 
Published: July 2006

Abstract
Background: No reliable, cost-effective serum test is available for assessment of liver fibrogenesis, the most serious complication of chronic inflammatory liver diseases (CLD). In sera of patients with CLD, we determined the concentration of connective tissue growth factor (CTGF), a secreted downstream mediator of the potent fibrogenic cytokine transforming growth factor β (TGF-β).
Patients and Methods: We studied 83 patients with CLD (17 with chronic hepatitis, 16 with histologically proven fibrosis, and 50 with cirrhosis) and 74 healthy individuals. Serum CTGF was measured by use of a sandwich immunoassay.
Results: The mean concentration of CTGF was highest in the fibrosis group (5.2-fold) and in the chronic viral hepatitis group (4.3-fold) but lower in those patients with fully developed cirrhosis. The area under the ROC curve (AUC) of CTGF for fibrosis vs control was 0.955 (95% confidence interval, 0.890–0.987). The CTGF/platelet ratio increased the detection limit for cirrhosis from 84% to 92% and the specificity from 85% to 87.5% (cutoff for CTGF was 364 μg/L, ratio 2.05).
Conclusion: CTGF in serum is a candidate marker of ongoing fibrogenesis in chronic liver diseases.
Cysteine cathepsins and caspases in silicosis
Authors: Lalmanach Gilles , Diot Elisabeth , Godat Emmanuel , Lecaille Fabien , Hervé-Grépinet Virginie 
Published: July 2006

AbstractSilicosis is an occupational pneumoconiosis caused by inhalation of crystalline silica. It leads to the formation of fibrohyalin nodes that result in progressive fibrosis. Alternatively, emphysema may occur, with abnormal destruction of collagen fibres in the advanced stages. Although the pathophysiological mechanisms remain unclear, it has been established that the lung responds to silica by massive enrolment of alveolar macrophages, triggering an inflammatory cascade of reactions. An imbalance in the expression of lung proteases and their inhibitors is implicated in extracellular matrix remodelling and basement membrane disruption. Moreover, exposure to silica can initiate apoptotic cell death of macrophages. This review summarises the current knowledge on cysteine cathepsins that have been ignored so far during silicosis and outlines the recent progress on cellular pathways leading to silica-induced caspase activation, which have been partly delineated.
Modeling the 3D structure of wheat subtilisin/chymotrypsin inhibitor (WSCI). Probing the reactive site with two susceptible proteinases by time-course analysis and molecular dynamics simulations
Authors: Facchiano Angelo M. , Costantini Susan , Di Maro Antimo , Panichi Daniela , Chambery Angela , Parente Augusto , Di Gennaro Simone , Poerio Elia 
Published: July 2006

Abstract
Comparative modeling and time-course hydrolysis experiments have been applied to investigate two enzyme-inhibitor complexes formed between the wheat subtilisin-chymotrypsin inhibitor (WSCI) and two susceptible proteinases. WSCI represents the first case of a wheat protein inhibitor active against animal chymotrypsins and bacterial subtilisins. The model was created using as template structure that of the CI-2A inhibitor from barley (PDB code: 2CI2), which shares 87% sequence identity with WSCI. Under these conditions of high similarity, the comparative modeling approach can be successfully applied. We predicted the WSCI 3D model and used it to investigate enzyme-inhibitor complex systems. Experimental observations indicated that chymotrypsin, but not subtilisin, in addition to cleavage at the primary reactive site Met48-Glu49, is able to hydrolyze a second peptide bond between Phe58 and Val59. Here, we report on cleavage of the peptide bond at the inhibitor's reactive site (Met48-Glu49) determined using time-course hydrolysis experiments; the same event was investigated for both subtilisin/WSCI and chymotrypsin/WSCI complexes using molecular dynamics simulations. The molecular details of the initial inhibitor-enzyme interactions, as well as of the changes observed during the simulations, allow us to speculate on the different fates of the two WSCI-proteinase complexes.