bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Extraction of Organomercury with 8-Quinolinol into Benzene
Authors: Sugimoto Takao , Naito Kunishige , Takei Shinsuke 
Published: July 2006

Abstract
The extraction of organomercury(II)(RHg+, R; ethyl, n-propyl, n-butyl, phenyl) with 8-quinolinol into benzene has been studied by means of spectrophotometry. This study confirmed that there was no co-extraction of electrically neutral species RHgOH by its investigation of the effect of the pH on the extraction of ethylmercury(II) chloride into benzene. Moreover, it was found that RHg+ forms 1:1 complexes with both HPO42− and PO43−. The formation constants of these complexes and of hydroxo complexes have been determined.
Efficient Synthesis of (±)-Solavetivone and (±)-[8,8-2H2]Solavetivone
Authors: Murai Akio , Sato Shingo , Masamune Tadashi 
Published: July 2006

Abstract
An alternative and efficient synthesis of the title compounds is described. The synthesis involves cycloaddition of 2-methylene-4-methoxy-6-methyl-4-cyclohexenylacetonitrile with methyl vinyl ketone as a key step.
Total Synthesis of (±)-Lubimin and (±)-Oxylubimin. I. Synthesis of (±)-15-Norsolavetivone and Related Compounds
Authors: Murai Akio , Sato Shingo , Masamune Tadashi 
Published: July 2006

Abstract
The total synthesis of (±)-15-norsolavetivone, a key intermediate in the synthesis of oxygenated spirovetivane stress metabolites, is described.
Total Synthesis of (±)-Lubimin and (±)-Oxylubimin. II. Transformation of (±)-15-Norsolavetivanes into (±)-Lubimin, (±)-Oxylubimin, and Related Compounds
Authors: Murai Akio , Sato Shingo , Masamune Tadashi 
Published: July 2006

Abstract
The transformation of (±)-15-norsolavetivone and related compounds, into (±)-lubimin and (±)-oxylubimin, which constitutes the total synthesis of these highly oxygenated spirovetivane phytoalexins, is described.
Synthesis of 3-(Substituted Methyl)-2-phenyl-4H-1-benzothiopyran-4-ones
Authors: Nakazumi Hiroyuki , Ueyama Tamio , Sonoda Hikaru , Kitao Teijiro 
Published: July 2006

Abstract
Reaction of 2-phenyl-4H-1-benzothiopyran-4-ones and related compounds with chloromethyl methyl ether and fuming sulfuric acid gave mainly 3-chloromethyl compound, whereas chloromethylation of methoxy-substituted thioflavones took place at another position or gave tris(chloromethyl) compound. 3-(Chloromethyl)thioflavone could be easily converted into various 3-(substituted methyl)thioflavones which showed significant antimicrobial activity against Trichophytons.
Convenient and Improved Synthesis of Tricarbonyl(1,2-dihydropyridine)iron Complex
Authors: Yamaguchi Ryohei , Nakazono Yutaka , Kawanisi Mituyosi 
Published: July 2006

Abstract
(N-Alkoxycarbonyl-1,2-dihydropyridine)tricarbonylirons are conveniently prepared in good yields by photo-irradiation in the presence of excess pentacarbonyliron without any solvent. 13C NMR spectra of the complexes are also described.
Ultrasounds in Synthetic Reactions. II. Convenient Methylenation of Carbonyl Compounds with Zinc–Diiodomethane
Authors: Yamashita Junzo , Inoue Yoshio , Kondo Takashi , Hashimoto Harukichi 
Published: July 2006

Abstract
Ultrasonic irradiation facilitates the methylenation of carbonyl compounds with zinc–diiodomethane reagent in tetrahydrofuran at room temperature.
Single Step Synthesis of 4H-1,4-Benzothiazines
Authors: Gupta Radha Raman , Kalwania Gopal Singh , Kumar Rakesh 
Published: July 2006

Abstract
Single step synthesis of substituted 4H-1,4-benzothiazines is reported by the condensation and oxidative cyclization of substituted 2-aminobenzenethiol with β-dicarbonyl compounds in DMSO. The structures of the synthesized compounds have been confirmed by their elemental analyses and spectral studies.
Kinetic Studies of the Base Equilibrium of Secondary Amines on the Surface of Sodium Dodecyl Sulfate Micelle by Means of the Ultrasonic Absorption Method
Authors: Yamashita Teruyo , Sumino Minako , Yano Hiroshige , Harada Shoji , Yasunaga Tatsuya 
Published: July 2006

Abstract
The ultrasonic relaxation absorption has been measured in aqueous solution of dipentylamine, dihexylamine, dioctylamine, N-methylphenethylamine, and N-ethylbenzylamine in the presence of the sodium dodecyl sulfate(SDS) micelle. The relaxation absorption has been ascribed to the base equilibrium of the amines on the surface of the micelle: RR′NH2++OH−\oversetkf\undersetkb\ightleftharpoonsRR′NH+H2O. The rate constants γ±2kf, kb, the apparent base dissociation constant Kb (=kb⁄γ±2kf), and the volume change in the base equilibrium ΔV were obtained, where γ± is the mean activity coefficient for RR′NH2+ and OH−. The dependence of the rate constants on Kb revealed that, in the detailed mechanism of the base equilibrium of the amines, RR′\underset(I)NH2++OH−\oversetk12\undersetk21\ightleftharpoons(RR′NH\underset(II)2+···OH−)\oversetk23\undersetk32\ightleftharpoonsRR′N\underset(III)H+H2O, the rate-determining step is the proton-transfer process, (II) \ightleftharpoons (III). The pKb values of the secondary amines on the surface of the SDS micelle were 0.94–1.26 smaller than the corresponding values in the aqueous solution, and the micellar effect on pKb was smaller than that of the primary amines. From the standpoint of the micellar effect, the structures of the amines solubilized in the micelle were discussed.
Studies on the Phase Transition near the Melting Point in Acetylferrocene
Authors: Sato Kumiko , Katada Motomi , Sano Hirotoshi , Konno Michiko 
Published: July 2006

Abstract
The entitled compound shows an anomalous temperature dependence of the mean-square amplitude of iron atoms derived from the Lamb-Mössbauer factor near the melting point. To clarify the anomaly, the crystal structure of this compound was determined at room temperature by X-ray diffraction. The crystal is monoclinic with space group P21/c, a=20.595(2), b=5.7909(4), c=18.840(2) Å, β=116.870(7)°, U=2004.4(3) Å3, and Z=8. Weissenberg and oscillation photographs taken at a high temperature lead us to propose a model in which the acetylferrocene molecules rotate around the central iron atoms.
New Transport Phenomenon. Enhanced Transport into a Membrane Due to the Presence of Polyelectrolyte
Authors: Nango Mamoru , Ohta Shozo , Maekawa Masako , Katayama Akira , Kuroki Nobuhiko 
Published: July 2006

Abstract
The transport of chromophore into a membrane in the presence of polyelectrolyte is enhanced much as it is in the presence of simple salt. The presence of polyelectrolyte with different kinds of counterions seem to modify this observed enhancement. The differences in enhanced transport into the cellulose membrane in the presence of polyelectrolyte may suggest a new model for reinterpretation of the transport phenomenon in a biological system.
Electron Paramagnetic Resonance and Optical Detection of Magnetic Resonance Studies of the Lowest Excited Triplet States of Purine, Benzimidazole, and Indazole in Benzoic Acid Host Crystals
Authors: Noda Masayo , Nagaoka Shin-ichi , Hirota Noboru 
Published: July 2006

Abstract
The triplet states (3ππ*) of purine, benzimidazole, and indazole are investigated in benzoic acid crystals by electron paramagnetic resonance (EPR) and optical detection of magnetic resonance (ODMR) techniques. Well resolved phosphorescence spectra were obtained at 4.2 K. The T1 states of purine and benzimidazole are located at 26409 and 26536 cm−1, respectively. The zero field splittings (ZFS) are D=0.1042 cm−1, |E|=0.0608 cm−1 for purine, and D=0.1123 cm−1, |E|=0.0270 cm−1 for benzimidazole. The decay rate constants of the triplet sublevels are determined at 1.5 K and are compared with those of indole. From the angular dependence of the EPR signals, the probable orientations of purine and benzimidazole in benzoic acid hosts are determined. From the observed hyperfine splittings (hfs) spin distribution of the T1 state of purine is estimated. (ρ6=0.20, ρ8=0.27, and ρ2=0.12). The effects of the nitrogen substitution in the pyrole ring of indole on the ZFS and spin distribution are discussed.
Analysis of Rotation-Vibration Bands of Sulfine, (CH2SO), by FT-IR and Microwave Spectroscopy
Authors: Koga Yoshinori , Takeo Harutoshi , Kondo Shigeo , Matsumura Chi , Saeki Shinnosuke 
Published: July 2006

Abstract
The rotation-vibration bands of a transient molecule, sulfine, (methanethial S-oxide), have been observed by FT-IR and analyzed with the aid of microwave data, a part of which has been newly obtained in this study. The band center frequencies for ν5 and ν9 are determined to be 1175.75 cm−1 and 762.07 cm−1, respectively. The good agreement between the observed and simulated band contours clarifies that the origin of these bands is sulfine.
The Synthesis of Green Rust II(FeIII1–FeII2) and Its Spontaneous Transformation into Fe3O4
Authors: Tamaura Yutaka , Yoshida Takashi , Katsura Takashi 
Published: July 2006

Abstract
Conditions for the synthesis of a pure green rust II with a definite chemical composition and its transformation reaction to Fe3O4 under a nitrogen atmosphere were studied. A pure green rust II with the composition of (Fe3+)1(Fe2+)2(SO42−)(OH−)5−2n(O2−)n was obtained by the air oxidation of an aqueous solution containing (0.05 mol dm−3) FeII and (0.3 mol dm−3) SO42− ions at pH 6.8 and 25 °C. This iron composition differs from those estimated previously; therefore, the green rust II synthesized here is designated as green rust II(FeIII1–FeII2). This green rust II is spontaneously transformed into Fe3O4 under a nitrogen atmosphere at 50–75 °C. It has been accepted that green rust II is transformed to Fe3O4 by oxidation. The above evidence suggests that the green rust II can be transformed into Fe3O4 not only by oxidation but also spontaneously without oxidants.
Arylation and 1-Alkenylation on α-Position of Ketones via Tributyltin Enolates Catalyzed by Palladium Complex
Authors: Kosugi Masanori , Hagiwara Isao , Sumiya Takao , Migita Toshihiko 
Published: July 2006

Abstract
The reaction of tributyltin enolates, prepared from tributyltin methoxide and enol acetates in situ, with aryl and 1-alkenyl bromides in the presence of dichlorobis(tri-o-tolylphosphine)palladium was found to give α-aryl and α-(1-alkenyl) ketones, respectively, in good yields with essentially complete retention of the enol acetate regiochemistry.
The Base-Catalyzed Isomerization of the (Iminodiacetato)-(N-methyliminodiacetato)cobaltate(III) and Bis(iminodiacetato)cobaltate(III) Ions
Authors: Kawaguchi Hiroshi , Ama Tomoharu , Yasui Takaji 
Published: July 2006

Abstract
The isomerization reaction among three geometrical isomers of [Co(ida)(mida)]− was studied in a basic aqueous solution. It has been found that the reaction scheme is u-fac\ightleftharpoonsmer\ightleftharpoonss-fac. The rates of these isomerization paths have been determined as the functions of pH and temperature. The rate of the u-fac\ightleftharpoonsmer change is considerably faster than that of the mer\ightleftharpoonss-fac change. The CD loss of the optically active u-fac isomer is caused by the isomerization process of u-fac\ightleftharpoonsmer. The isomerization of the [Co(ida)2]− system has also been measured, and the rate data analysed according to the same scheme as that used for the [Co(ida)(mida)]− system. It is suggested that the isomerizations of the [Co(ida)(mida)]− and [Co(ida)2]− systems proceed through a conjugatebase intermediate.
Synthesis and Cation-Complexing Ability of Oxo Crown Ethers Containing a Ferrocene Nucleus
Authors: Izumi Taeko , Tezuka Takeshi , Yusa Sachiko , Kasahara Akira 
Published: July 2006

Abstract
Fifteen new oxo crown ethers having a ferrocene unit as an integral part of the ring member are reported. These oxo crown ethers were synthesized by the reaction of 1,1′-bis(chloroformyl)ferrocene with oligoethylene glycols or heterocyclic dialcohol compounds such as 2,6-bis(hydroxymethyl)pyridine by the high dilution method. Complexing ability of these compounds with alkali, alkaline earth, and transition metal cations was measured by the solvent extraction method.
Effect of the Base Stacking Association on the Phosphate Ionization of 2′-Deoxyguanosine 5′-Monophosphate
Authors: Hirota Kazumi , Inoue Yoshio , Chûjô Riichirô 
Published: July 2006

Abstract
The concentration dependence of 31P chemical shifts at neutral pH has been measured for 2′-deoxyguanosine 5′-monophosphate and deoxyribose 5-monophosphate. The chemical shifts are sensitive to the variation of concentration, and are affected by the presence or absence of the base. The variations of 31P chemical shifts correspond to those of pKa′ values. The concentration dependence of 31P chemical shift of deoxyribose 5-monophosphate can be explained by the ionic strength change accompanied by the concentration change, whereas that of the nucleotide can not be interpreted with the aid of it alone. The phosphate group of the nucleotide ionizes more readily at higher concentration. There is an additional effect other than ionic strength on the pKa′ eand it is caused by the presence of the base. The appearance of the concentration effect owing to the base is attributable to the base stacking association. The measurements at different temperatures support this conclusion.
Acid-catalyzed Backbone Rearrangement of 5,6-Epoxyalnusanes and Preparation of Daturadiol
Authors: Tori Motoo , Takai Masaki , Matsumoto Yuzo , Moriyama Yoshihiko , Tsuyuki Takahiko , Takahashi Takeyoshi , Ohnishi Hiraku , Itai Akiko , Iitaka Yoichi 
Published: July 2006

Abstract
Epoxidation of alnus-5-en-3β-yl acetate with m-chloroperbenzoic acid gave a 5β,6β-epoxide as a main product together with a 5α,6α-epoxide as a minor product. Treatment of the α-epoxide with BF3·OEt2 afforded a 1(10),5-diene and a mixture of 6α-hydroxy-12- and -18-ene derivatives. The 12-ene was converted into daturadiol (=olean-12-ene-3β,6β-diol).
Branched-chain Sugars. XXXV. The Synthesis of l-Rubranitrose (2,3,6-trideoxy-3-C-methyl-4-O-methyl-3-nitro-l-xylo-hexopyranose)
Authors: Yoshimura Juji , Yasumori Toshio , Kondo Tatsuya , Sato Ken-ichi 
Published: July 2006

Abstract
The title compound was stereoselectively synthesized from methyl 2,6-dideoxy-4-O-methyl-β-l-thero-hexopyranosid-3-ulose (11) through the successive conversions; cyanomesylation, reductive spiro aziridine formation, reductive ring-opening to the methyl-branched amino sugar, oxidation to the corresponding nitro sugar.
Branched-chain Sugars. XXXVI. A New Synthesis of Methyl 4-O-Benzoyl-3-benzoylamino-2,3,6-trideoxy-3-C-methyl-α-l-xylo-hexopyranoside, a Derivative of the Branched-chain Amino Sugar of Antibiotic A35512B
Authors: Yasumori Toshio , Sato Ken-ichi , Hashimoto Hironobu , Yoshimura Juji 
Published: July 2006

Abstract
The title compound was synthesized from methyl 4-O-benzyl-2,6-dideoxy-β-l-threo-hexopyranosid-3-ulose (19) through cyanomesylation, reductive spiro aziridine formation, and reductive ring-opening. When (2-methoxyethoxymethyl) group was used as the protecting group at O-4 of the above intermediate, it could not be removed at the final stage.
Synthesis of a Heat-stable Enterotoxin (STh) Produced by a Human Strain SK-1 of Enterotoxigenic Escherichia coli
Authors: Ikemura Haruo , Yoshimura Shoko , Aimoto Saburo , Shimonishi Yasutsugu , Hara Saburo , Takeda Tae , Takeda Yoshifumi , Miwatani Toshio 
Published: July 2006

Abstract
A peptide with the amino acid sequence proposed for a heat-stable enterotoxin (STh) produced by a human strain SK-1 of enterotoxigenic Escherichia coli was synthesized by a conventional method. Synthetic STh evoked fluid secretion in suckling mice at a dose of 0.8 ng, which is similar to the effective dose of native STh. The fluid secretion was completely inhibited by antisera raised against the native toxin. Furthermore, synthetic STh showed the same 1H-NMR spectrum and heat-stability as native STh.
Sensitization of Polycrystalline SrTiO3 Photoanodes by Lanthanum Doping
Authors: Chang Byong-Tae , Campet Guy , Claverie Jean , Hagenmuller Paul 
Published: July 2006

Abstract
The behaviors of polycrystalline LaxSr1−xTiO3(x≤0.05) electrodes in a photoelectrochemical cell for water decomposition have been investigated in aqueous NaOH electrolyte. The lanthanum substitution for strontium resulted in impressive visible photosensitization of the corresponding electrodes under anodic polarization. This visible photoresponse is based on the relatively deep subband gap states introduced into the forbidden band by lanthanum doping, in analogy with the polished undoped SrTiO3 electrodes reported previously.
The Crystal and Molecular Structure of 3,4-Dimethyl-2,5-diphenyl-3,4-dihydro-3a-thia-1,3,4,6-tetraazapentalene
Authors: Iwasaki Fujiko , Akiba Kin-ya 
Published: July 2006

Abstract
The crystal structure of 3,4-dimethyl-2,5-diphenyl-3,4-dihydro-3a-thia-1,3,4,6-tetraazapentalene has been determined by the X-ray method. The crystals are orthorhombic, space group Pbcn, a=14.533(4), b=9.285(3), c=11.305(2) Å, V=1525.4(6) Å3, Z=4, Dx=1.343 Mg m−3. The final R value is 0.060 for 1107 reflections. The molecule has an exact C2 symmetry, with the central S–C bond coincident with the 2-fold axis of the crystal symmetry. The length of 1.904 Å of the two equivalent S–N bonds indicates that the molecule is a tetraaza analogue of the thiathiophthenes. The length of this S–N bond is 9% longer than the N–S single bond and significantly less than the sum of the van der Waals radii.
Structure and Properties of Thallium(I) Formate Solutions
Authors: Ozutsumi Kazuhiko , Ohtaki Hitoshi , Kusumegi Asao 
Published: July 2006

Abstract
The structure of thallium(I) formate aggregates in concentrated aqueous thallium(I) formate solutions was investigated by the X-ray diffraction method at 25 °C for solutions A (10.77 mol dm−3) and B (3.493 mol dm−3). The former solution had the density of 3.189 g cm−3 and the CH2O⁄CTl mole ratio of 2.59, where Ci represents the total concentration of species i, and was an almost saturated solution at room temperature. From the analysis of the X-ray diffraction data of solution A, thallium(I) formate was found to be present as a tetramer Tl4(O2CH)4. The nearest interatomic distances between thallium(I) and atoms within the formate ions in the tetramer were determined as Tl–O: 2.79(1) Å and Tl···C: 3.33(2) Å. The nonbonding Tl···Tl distances within the aggregate were estimated to be 3.92(1) Å, 4.34(1) Å, and 4.79(1) Å. The Tl–OH2 bond length was also determined to be 3.22(3) Å, which was much larger than the distance expected from the sum of the ionic radius of thallium(I) ion (≈1.4 Å) and size of a water molecule (≈1.4 Å). A comparison of the radial distribution function of solution A with that of solution B, which had the CH2O⁄CTl mole ratio of 13.5, indicated that the aggregate decomposed by dilution. Raman spectra of four different thallium(I) formate aqueous solutions of 3.493 to 10.77 mol dm−3 were measured and the frequencies of the C–O and C=O stretchings of formate ions in the solutions were compared with those of free formate ion. Band shifts of the two frequencies observed for concentrated thallium(I) formate solutions indicated the existence of bridge-type formate ions coordinated to thallium(I) ions, and the result agreed with that observed by the X-ray diffraction analysis. Densities, refractive indices, viscosities and conductivities were measured for thallium(I) formate aqueous solutions with varying concentrations.
Cobalt(III) Complexes with [N6−nXn] type Ligands. IV. The Preparation and Properties of Tetraammine(salicylideneaminato)cobalt(III) and Diamminebis(salicylideneaminato)cobalt(III) Complexes
Authors: Yamamoto Yoshihisa , Toyota Eiko 
Published: July 2006

Abstract
Tetraammine(salicylideneaminato)cobalt(III) complexes, (Remark: Graphics omitted.) (X: Cl, NO3, ClO4, and picrate) and diamminebis(salicylideneaminato)cobalt(III) complexes, (Remark: Graphics omitted.) (X: Cl, NO3, ClO4, and picrate), have been isolated from a reaction mixture of CoCl2·6H2O, 25% aqueous ammonia, 30% H2O2 and salicylaldehyde, and characterized. In the latter complexes, the three isomers of green, orange and brown color have been isolated by column chromatography on alumina and their configurations have been established by their NMR spectra, i.e., the configuration of the green complex is in the trans-trans-trans positions for two ammine ligands, and two phenoxyl groups and two CH=NH groups of the coordinated salicylideneaminato ligands, respectively, while those of the orange and brown complexes are in the trans-cis-cis and cis-cis-trans positions, respectively.
Formation Process of Aluminium Nitride by the Vapor-phase Reaction of Aluminium Trichloride with Ammonia
Authors: Saeki Yuzo , Park Suh Ho , Yajima Akimasa , Akiyama Masayo 
Published: July 2006

Abstract
The reaction products of gaseous AlCl3 with ammonia were AlCl3·3NH3 at 200–500 °C, AlN, AlCl3·3NH3, NH4Cl at 550–900 °C, and AlN, NH4Cl at 1000 °C. AlN is considered to be formed by the reaction of gaseous AlCl3·3NH3, formed by the reaction of gaseous AlCl3 with ammonia, with ammonia above ca.550 °C.
Temperature and Isotope Effects in the Reactions of Phenylcarbene with Acetone
Authors: Tomioka Hideo , Ozaki Yasuji , Nakamura Hiroyuki , Izawa Yasuji 
Published: July 2006

Abstract
Phenylcarbene generated in acetone solution gives oxirane, vinyl ether and 1,3-dioxolane presumably via initial attack of the singlet state on the lone pair electrons of carbonyl oxygen leading to a carbonyl ylide, whereas a C–H insertion product arising from the triplet markedly increases in matrix environments.
The Reaction of Diethyl Acyl Phosphites with α,β-Unsaturated Carbonyl Compounds
Authors: Okamoto Yoshiki , Azuhata Toshio 
Published: July 2006

Abstract
Diethyl acetyl and diethyl benzoyl phosphites reacted with propenal and 3-buten-2-one to give 1,4-addition products respectively. While the reaction of diethyl acetyl phosphite with 2-butenal and 2-methyl- and 3-phenylpropenals gave 1,2-addition products exclusively.
Preliminary Work on Orientation of Nematic Liquid-Crystalline Molecule by Electronic Spectra
Authors: Kobayashi Michio , Kasahara Toshiyuki , Nakajima Keihachiro , Maruyama Kazunori , Tanizaki Yoshie 
Published: July 2006

Abstract
Absorption spectra of a nematic liquid-crystalline molecule (4-butyl-4′-ethoxyazobenzene) were measured in sandwich-type cells with very thin gaps which ranged from 0.2 to 1.0 μm when the cells were empty. The intensity ratio of the first (354 nm) to second (240 nm) band in the liquid state (86 °C) decreases as the state changes into liquid-crystalline (LC) states (70 and 48 °C). According to results of dichroism analysis and MO calculation, the 354 nm and 240 nm bands are due to π-π* transitions polarized along the molecular long and short axes, respectively (with an angle of about 66°to each other). This finding coupled with an assumption that the molecular orientation of the liquid state is isotropic, allows a qualitative discussion on the orientation of molecule in the LC state, leading to a conclusion that the molecular long axis against the cell surface takes two kinds of orientation with respective tendencies to be parallel in the interface region and perpendicular in the bulk region.