bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and Spectroscopic Studies of (Diethylenetriamine)cobalt(III) Complexes with l-Penicillaminate or Its Derivative
Authors: Wakayama Katsuhiko , Okamoto Ken-ichi , Einaga Hisahiko , Hidaka Jinsai
Published: July 2006

The (diethylenetriamine)(l-penicillaminato)cobalt(III) complex, [Co(l-pen)(dien)]+, was chromatographically separated into three isomers, trans(NiN), trans(NiO) and trans(NiS). Each of these gave a corresponding isomer of the (diethylenetriamine)(S-methyl-l-penicillaminato)cobalt(III) complex, [Co(l-smp)(dien)]2+, by the reaction with dimethyl sulfate. The (triammine)(S-methyl-l-penicillaminato)cobalt(III) complex was also derived from the corresponding l-pen complex, [Co(l-pen)(NH3)3]+. The absorption and CD spectra of the l-pen complexes were compared with those of the l-smp ones to specify the geometrical configurations. The l-pen complexes exhibited characteristic absorption behavior and CD spectra in the region of (14–30)×103 cm−1.
Aryliminodimagnesium Reagents. IV. The Independent Preparation of Unsymmetrically Substituted Azoxyarene Isomers and Their Deoxygenation
Authors: Okubo Masao , Koga K\={o}ji
Published: July 2006

By use of the condensation reaction of aryliminodimagnesium reagents (ArN(MgBr)2) with nitroarenes, six symmetrical and eight unsymmetrical azoxyarenes including four pairs of isomers were prepared in 40–80% yields. The deoxygenation reaction of the azoxyarenes by treating with five molar equivalents of p-MeOC6H4N(MgBr)2 at 55 °C in tetrahydrofuran was also studied, and the reactivity of deoxygenation was correlated to the shift of the electronic absorption maximum of azoxyarene.
Further Polarographic Studies on the Condensation Products of Dehydro-l-ascorbic Acid with o-Phenylenediamine in Acetate Buffer, pH 3.6
Authors: Ohmori Mitsuaki , Tsujimoto Yuji , Takagi Masanosuke
Published: July 2006

Three polarographic reduction waves, which appear when dehydro-l-ascorbic acid (DAA) is treated with o-phenylenediamine (OPD) in acetate buffer, pH 3.6, were renivestigated by comparing with those of the synthesized products from DAA and OPD. A reaction scheme of DAA with OPD is presented and the characteristics of the reactions are discussed.
Synthetic Study on Peptide Antibiotic Nisin. I. The Synthesis of Ring A
Authors: Wakamiya Tateaki , Shimbo Kuniaki , Sano Akihiko , Fukase Koichi , Shiba Tetsuo
Published: July 2006

Synthesis of the ring A, a cyclic sulfide peptide part containing dehydroalanine residue, in peptide antibiotic nisin was successfully achieved by applications of two novel procedures. First, a sulfide ring was derived from a cyclic disulfide peptide by desulfurization with P(Et2N)3. Secondly, for the preparation of dehydroalanyl residue, a simple and convenient method through Hofmann degradation of 2,3-diaminopropionyl residue was newly exploited in the presence of sulfide linkage.
The Copper-catalyzed Autoxidation of Cysteine.The Amount of Hydrogen Peroxide Produced under Various Conditions and the Stoichiometry of the Reaction
Authors: Hanaki Akira , Kamide Hiroko
Published: July 2006

Hydrogen peroxide is shown to be produced as an intermediate from oxygen in the copper-catalyzed autoxidation of cysteine. The amounts of cysteine oxidized and of hydrogen peroxide formed varied depending on the reaction conditions employed. The perpxide upon forming was spontaneously utilized for the oxidation of cysteine. As a result, the ratio of the concentration of hydrogen peroxide formed to cysteine oxidized is variable depending on the conditions. But, in dilute solutions, where the oxidation by the peroxide was slow, a stiochiometric relation of 2:1 was obtained between cysteine consumed and hydrogen peroxide produced. The rate of autoxidation is dependent on the concentration of oxygen dissolved. The double reciprocal plot of the rate against the concentration of oxygen gives a straight line, which indicates a possibility of the Michaelis-Menten type mechanism concerning the reoxidation or oxygenation of Cu(I) species.
Lead Tetraacetate Oxidation of Humulene and Conformational Analysis of the Produced Humulatrienediols
Authors: Shirahama Haruhisa , Hayano Kiyoharu , Arora Gurdial Singh , Osawa Eiji , Matsumoto Takeshi
Published: July 2006

Humulene was oxidized by lead tetraacetate in benzene to give 2,5,9-humulatrien-7-ol acetate and 1,5,9-humulatriene-3,7-diol diacetates. Conformational analysis of 1,5,9-humulatriene-3,7-diols was performed by NMR spectroscopy and molecular mechanics calculations.
Temperature Dependence of Absorption Spectra of Chlorophyll a in Hydrocarbons over the Temperature Range 300–77 K. Enthalpy and Entropy Changes for the Formation of Dimeric Chlorophyll a
Authors: Hoshino Mikio , Ikehara Kiyoshi , Imamura Masashi , Hama Yoshimasa
Published: July 2006

The absorption spectra of chlorophyll a in isopentane, 3-methylpentane, and methylcyclohexane solutions were studied over the temperature range 300–77 K. In those hydrocarbon solutions which were prepared using methanol treatment, chlorophyll a forms hydrated dimer at low temperatures. The dimer has an absorption peak at 695 nm at 160 K, which gradually shifts to 706 nm with decreasing temperature from 160 K to 77 K. The enthalpy change (–ΔH) for the formation of the dimer was obtained to be 41.0±0.8 kJ mol−1, independent of the solvent used. The entropy changes (–ΔS) were 113±8 J K−1 mol−1 for isopentane, 118±8 J K−1 mol−1 for 3-methylpentane and 128±8 J K−1 mol−1 for methylcyclohexane solutions. Comparative studies carried out of the solutions prepared without the methanol treatment suggest the existence of two kinds of hydrated monomeric chlorophyll a.
The Adsorption of Chloromethanes on KCl. The Role of the Surface Ions as Adsorption Sites
Authors: Chikazawa Masatoshi , Amada Masatoshi , Kanazawa Takafumi
Published: July 2006

The adsorbed amounts of chloro-substituted methanes, such as CH2Cl2, CHCl3, and CCl4, for KCl particles were measured by a volumetric method at various temperatures, and the isosteric heats of adsorption and differential entropies of the adsorbed molecules were estimated from the adsorption isotherms. The order of magnitude of the heats of adsorption at a coverage of θ=0.5 was found to be CH2Cl2>CHCl3>CCl4. Moreover, a plot of the dipole moments of the three adsorbates vs. the adsorption heat values gave a straight line. Therefore, the differences among the adsorption heats of the three adsorbates is mainly caused by an orientation of their dissimilar dipoles to the surface. It may be concluded that the chloro-substituted methanes are adsorbed on surface anions of KCl powder.
The Heat Capacities of Lithium, Sodium, Potassium, Rubidium, and Caesium Nitrates in the Solid and Liquid States
Authors: Ichikawa Kazuhiko , Matsumoto Toshiyuki
Published: July 2006

The heat capacities, Cp, of the alkali metal nitrates, MNO3 (M= Li, Na, K, Rb, and Cs), in the solid and liquid states have been measured between 50 and 450 °C by means of adiabatic calorimetry. We have measured with a fair degree of accuracy the Cp values for the MNO3 systems, because the existing data on NaNO3 and KNO3 above 250 °C are quite scanty. Some empirical rules, some of which may extend to other salts, have been obtained from the results on Cp for the five alkali nitrates in the solid and liquid states. For the molten MNO3, the heat capacities at a constant volume, CV, were obtained from the thermodynamical relationship between CV and Cp, using the experimental values of Cp; the CV values have been interpreted in terms of the interionic and intraionic portions.
Self-diffusion and Melting in the Plastic Phases of Neopentane as Studied by NMR Relaxation at High Pressures
Authors: Takeda Sadamu , Soda Gen , Chihara Hideaki
Published: July 2006

Proton spin-lattice relaxation time T1 in the plastic phase of 2,2-dimethylpropane (neopentane) was measured at 10 MHz up to 170 MPa between 192.7 and 308.2 K. T1 near the melting point is determined by self-diffusion. The enthalpy and volume of activation of this motion suggest that self-diffusion occurs through a single vacancy mechanism. The correlation time of self-diffusion at the melting point (Tf) is (3.2±0.5)×10−7 s irrespective of external pressure. The diffusion rate is a function only of Tf⁄T, i.e. the law of corresponding states holds. The feature of activation properties of self-diffusion is strongly correlated with the melting phenomenon. The melting curve of the phase diagram was also determined and a possibility of existence of another plastic phase was found above 40 MPa.
Synthesis and Characterization of Imidazolate-bridged Copper(II) Complexes of Triangular Skeleton
Authors: Okawa Hisashi , Mikuriya Masahiro , Kida Sigeo
Published: July 2006

New polynuclear copper(II) complexes of the composition [CuL(im)]X (L=N,N,N′,N′-tetramethylethylenediamine (tmen), bip, phen; X=ClO4, PF6, BF4; im= imidazolate ion) have been prepared. Cryomagnetic measurements have indicated that the complexes involve a trianglar-trinuclear skeleton and an antiferromagnetic spin-exchange interaction operates between copper(II) ions; exchange integrals being evaluated at −37–−45 cm−1.Based on the Dreiding model consideration of the complexes and the crystal structure of [Cu(tmen)(imH)2](ClO4)2, a trinuclear structure of the triangular skeleton with imidazolate bridges, (Remark: Graphics omitted.), was supposed for the complexes.
Rapid Diffusion of Oxygen Ions in Indium Oxide during Reduction-oxidation
Authors: Otsuka Kiyoshi , Yasui Takao , Morikawa Akira
Published: July 2006

Rapid diffusion of oxygen ions in indium oxide particles has been suggested by measuring the distribution of 18O ions after oxidation of reduced-indium oxide by 18O2 (gas). This result explains the observation that the reduced-indium oxide is one of the most efficient compounds among the reduced metal oxides for reduction of H2O, CO2, or NO.
Macroscopic and Microscopic Behavior of the Eluent in Liquid Chromatography
Authors: Fukuhara Ken-ichi , Nakamura Asao , Tsuboi Masamichi
Published: July 2006

By injecting an isotope pulse into the eluent of liquid chromatography, it has been shown that the eluent flow does not go into the stationary phase, while each of the molecules in the eluent is replaced by an equivalent molecule originally contained in the stationary phase. Meanwhile, an appropriate method for determining the t0 value is given.
Nitration of Aromatic Heterocycles with Palladium(II) Acetate and Sodium Nitrite
Authors: Itahara Toshio , Ebihara Reiko , Kawasaki Kazukuni
Published: July 2006

Treatments of 1,3-dimethyluracil, 1-methyl-2-pyridone, and thiophene with palladium(II) acetate and sodium nitrite gave the corresponding nitro-substituted products.
Reinvestigation of the Synthetic Reaction of Dimethylamino-1,3-indandione
Authors: Ito Masaaki , Abe Kazuo , Sasaki Teruji , Misono Kenzo
Published: July 2006

One step preparation of dimethylamino-1,3-indandione (1) from salicylaldehyde with glycine betaine was reinvestigated. Reaction conditions to give the best yield of 1, characterization of a minor product (2-acetoxybenzylidene diacetate), and reaction pathway were described.
A Convenient Synthesis of C(2)-Substituted Cephalosporins
Authors: Torii Sigeru , Tanaka Hideo , Saitoh Norio , Siroi Takashi , Sasaoka Michio , Tada Nobuhito , Nokami Junzo
Published: July 2006

Replacement of the C(2)-substituents of 2-acetoxy- or 2-methoxycephalosporin with nucleophiles was performed efficiently in dichloromethane in the presence of acid-catalysts, affording cephalosporins bearing heteroaromatic moieties, sulfenyl, and alkoxyl groups at the C(2)-position.
Branched-chain Sugars. XXXIV. Synthesis of Methyl Dihydroeurekanate
Authors: Yoshimura Juji , Hara Kazutoshi , Matsuzawa Masafumi
Published: July 2006

Methyl dihydroeurekanate; methyl 6-deoxy-4-C-[(S)-1-hydroxyethyl]-2,3-O-methylene-d-galactonate was synthesized from benzyl 6-deoxy-4-C-[(S)-1-hydroxyethyl]-2,3-O-methylene-d-galactopyranoside.
Lattice Dynamical Analysis of MgO
Authors: Kida Akiko , Miura Mitiko , Murata Hiromu
Published: July 2006

The lattice dynamical properties of MgO are studied using a model based on the Birman method, which is different from the conventional point-like atom model. The model includes three kinds of forces: the short-range, the long-range Coulomb, and the long-range polarization interactions. The long-range interactions are dependent on the magnitude of the expansion of the electron distribution. The degrees of the expansion for Mg and O (wMg and wO) are estimated from the X-ray data. The calculated phonon dispersion curves agree with the observed curves in the case of wMg=0.35 Å and wO=0.73 Å, which are nearly equal to the estimated values, 0.35 and 0.65 Å.
The Ultraviolet Photoelectron Spectroscopy of Aliphatic Hydrocarbons and Tetramethylsilane in the Solid State
Authors: Seki Kazuhiko , Inokuchi Hiroo
Published: July 2006

He I, Ne I, and Ar I ultraviolet photoelectron spectra were measured for solid hexane, 3-methylpentane, 2,2-dimethylbutane, neopentane, tetramethylsilane, cyclohexane, and 1-hexene deposited on a substrate at the temperature of liquid nitrogen. The spectra of all the compounds except hexane showed valence-band features. The threshold ionization potential was 7.6–8.9 eV, with a lowering of the threshold from the gas to the solid phase (polarization energy PS) of 1.2–1.8 eV. These PS values are in reasonable agreement with theoretical model calculations. To clarify the effect of intra- and intermolecular factors on PS, the observed PS values were compared with those of liquid-phase and solid-aromatic hydrocarbons. For compounds in which the bottom of the conduction band lies above the vacuum level, the polarization energy data showed that electrons with energies between these states are also emitted, possibly without any excitation of electrons to the conduction band in the bulk of the solid.
Ozonization of Organic Compounds. VII. Carboxylic Acids, Alcohols, and Carbonyl Compounds
Authors: Niki Etsuo , Yamamoto Yorihiro , Saito Tsuneo , Nagano Keiji , Yokoi Seiichi , Kamiya Yoshio
Published: July 2006

The rate and products of the ozonization of carboxylic acids, alcohols, and ketones have been studied in water at 30 °C. The ozonization of alcohols gave corresponding carbonyl compounds as major product. The ozonization of ketones brought about primarily the carbon-carbon bond cleavage and gave carboxylic acids. Saturated carboxylic acids such as acetic acid, propionic acid, and isobutyric acid were ozonized only slowly in neutral water, but they were ozonized faster in alkaline aqueous solution. On the other hand, α-hydroxy carboxylic acids such as glycolic acid and lactic acid were ozonized even in pure water. The mechanism of ozonization of these compounds and the effect of pH are discussed.
Crystal Structure of Adenine-1-(2-Carboxyethyl)uracil (1 : 1) Complex. A Model for Interactions of Amino Acid Side Chains with Nucleic Acid Base Pair
Authors: Fujita Shigeo , Takenaka Akio , Sasada Yoshio
Published: July 2006

As a model for protein-nucleic acid interactions, crystals of the title complex were prepared from a water–ethanol (1 : 1) solution containing equimolar amounts of adenine and 1-(2-carboxyethyl)uracil. The space group is P21/c with the unit cell dimensions of a=12.567(1), b=13.358(1), c=8.032(1) Å and β=93.28(1)°. The crystal structure was determined by X-ray analysis. The final R value was 0.053. The adenine and uracil moieties form a reversed Hoogsteen base pair in which N(7) and N(6) of adenine are hydrogen-bonded with N(3) and O(2) of uracil, respectively. The carboxyl group is dissociated and hydrogen-bonded to the protonated N(1) of adenine in the adjacent base pair at a distance of 2.542(3) Å. It is suggested that the protonation of adenine–uracil reversed Hoogsteen base pair could occur to make the base pair more stable, and the dissociated carboxyl group may be hydrogen-bonded to it in the protein–nucleic acid interactions.
Pressure-Volume-Temperature Relations and Isotropic-nematic Phase Transitions for 4-(trans-4-Pentylcyclohexyl)benzonitrile
Authors: Ichimura Hajime , Shirakawa Toshiaki , Tokuda Taneki , Seimiya Tsutomu
Published: July 2006

Pressure-volume isotherms of 4-(trans-4-pentylcyclohexyl)benzonitrile were directly measured by means of piston-cylinder method at various temperatures. From the relation of the molar volume and the transition temperature which was determined by its clearing point, the parameter ∂lnTc⁄∂lnVc, was found to assume a value of −5.24, which should be closely related with the intermolecular potential energy. The value of this parameter increased correlatively with the alkyl chain length in the homologous series of 4-(trans-4-alkylcyclohexyl)benzonitriles.
Syntheses, Structure, and Properties of Several Bis{(alkylthio)acetato}copper(II)–Amine Adducts
Authors: Ouchi Akira , Sato Yoshiyuki , Yukawa Yasuhiko , Takeuchi Toshio
Published: July 2006

The crystal and molecular structure of tetrakis{(isopropylthio)acetato}bis(quinoline)dicopper(II) (1), bis(dibenzylamine)bis{(ethylthio)acetato}copper(II) (2), and bis{(isopropylthio)acetato}tris(isoquinoline)copper(II) (3) were determined by the X-ray diffraction method. The final R values obtained are 0.041, 0.055, and 0.078 for 1, 2, and 3 respectively. 1 is green in color and is orthorhombic with the space group Pcab. It has a dimer structure similar to that of the copper(II) acetate hydrate, where four (alkylthio)acetate liagnds bridge both copper(II) atoms. 2 is violet in color and is monoclinic with the space group A2/a. It has a square-palnar geometry, and no atoms are coordinated to the copper(II) atom from the axial direction, probably because of the steric effect of the large dibenzylamine molecules. 3 is blue in color and is triclinic with the space group P\bar1. It has potentially a hepta-coordinate geometry, where one nitrogen atom and two oxygen atoms ligate from the axial direction of the CuN2O2 plane.
A Calorimetric Study on the Relative Thermal Stability of Some Bis(diamine)cobalt(III) Complexes in a Solid Phase
Authors: Tsuchiya Ryokichi , Uehara Akira , Wazumi Toshio , Muramatsu Yoshinori
Published: July 2006

The enthalpy changes (ΔH) in the reaction of trans-[CoX2(AA)2]X·mHX·nH2O-type complexes with an alkaline sodium sulfide solution were calorimetrically measured at 25 °C, where AA is diamine and X is Cl−, Br−, or ClO4−; m=0 or 1, and n=0, 0.5, 1, or 2. The thermal stabilities were found to decrease in the following orders for both dichloro and dibromo complexes: 1,2-ethanediamine>l- or d-1,2-propanediamine>racemic 1,2-propanediamine,d,l-2,3-butanediamine>meso-2,3-butanediamine>2-methyl-1,2-propanediamine, 1,2-ethanediamine>1,3-propanediamine, and meso-2,4-pentanediamine>d,l-2,4-pentanediamine. The complexes containing six-membered diamine chelate rings were less stable than those containing five-membered diamine chelate rings. The dibromo complex bromides were less stable than the corresponding dichloro complex chlorides.
The Affinity for Carbon Monoxide, Electrochemical and Spectral Properties of Binuclear Copper(I) Complexes
Authors: Kitagawa Susumu , Munakata Megumu , Miyaji Noboru
Published: July 2006

Binuclear copper(I) complexes [CuXL]2(X=Cl− and I−; L=2,2′-bipyridine, 1,10-phenanthroline, and their derivatives) have been synthesized in acetone, which react with CO reversibly to give crystalline carbonyl adducts [Cu2X2L2(CO)]. The cyclic voltammograms of [CuXL]2 and [Cu2X2L2(CO)] show two couples of coppercentered oxidation-reduction waves, indicative of binuclear structure. One couple of waves in [Cu2X2L2(CO)] alone shifts to the anodic region, exhibiting the formation of monocarbonylated complexes. All the half-wave potentials are primarily governed by the basicity of a ligand L, and the contribution of a coordinated CO to the stabilization of CuI state by π back-bonding is found. The equilibrium constants of the reaction, [CuXL]2+CO\oversetKco\ightleftharpoons[Cu2X2L2(CO)], are lowered with the decrease in the transition energy of the ligand←metal charge transfer of [CuXL]2. On this basis, it is concluded that CO competes with L concerning π back-bonding with copper(I). The νco values of the coordinated CO exhibit apparent L-dependence, which is accounted for by the competition between Cu–L and Cu–CO π-bonding, and hence, νco values are useful probe to inquire into the nature of Cu–CO bonding among these copper(I) complexes.
Immunoassay Using a Metal-complex Compound as a Chemiluminescent Catalyst. I. Iron(III)phthalocyanine as a Labeling Reagent
Authors: Hara Tadashi , Toriyama Motohiro , Tsukagoshi Kazuhiko
Published: July 2006

A synthesized metal-complex compound with catalytic activity for a chemiluminescence reaction has been used for the first time as a labeling reagent for immunoassay. Several complex compounds of iron(III) and cobalt(II) were synthesized, and their catalytic activities for the chemiluminescence reaction between 5-amino-2,3-dihydro-1,4-phthalazinedione (luminol) and hydrogen peroxide (H2O2) were examined. Iron(III) 4,11,18,25-tetracarboxyphthalocyanine (TCP-Fe(III)) showed the highest catalytic activity. The immunoassay of free albumin was carried out by a competitive method using albumin labeled with TCP–Fe(III) by means of the carbodiimide method; free albumin in the range of 2 to 1000 μg/tube could be determined with a coefficient of variation of from 6 to 16% in 5 analyses.
An Improved Preparation and Characterization of Tetrahedral CoII and CoIII Complexes with Dodecatungstate as the Tetrahedral Ligand
Authors: Nomiya Kenji , Kobayashi Ryoichi , Miwa Makoto
Published: July 2006

Tetrabutylammonium salt of the 12-tungstoheteropolyanion with central CoII as the heteroatom in a tetrahedral oxygen environment, [CoIIW12O40]6−, has been prepared by an improved manner. This manner remarkably shortens the total time needed for preparation, especially the time for purification, and gives a compound of a high purity. The corresponding CoIII compound has been obtained by oxidation with potassium peroxodisulfate from the potassium salt of the CoII compound; its spectroscopic data (IR, near-infrared, UV-vis, and MCD) are presented.
Hydration of Iodide Ions in Nitrobenzene from Charge-transfer-to-solvent Spectra and 1HNMR
Authors: Ito Kazuaki , Iwamoto Etsuro , Yamamoto Yuroku
Published: July 2006

The charge-transfer-to-solvent (c.t.t.s.) spectrum of the iodide ion in nitrobenzene was observed in the visible region, the intensity of the spectrum being lowered by addition of a small amount of water to the solution. From the spectral changes, the first, second, and third hydration constants, K1=3.5, K2=2.6, and K3=1.4 (mol−1 dm3) were determined. On the basis of 1H NMR of water in nitrobenzene solutions in conjunction with the hydration constants obtained from the spectra, it was suggested that a fraction of the water molecules bound to the iodide ion is hydrogen bonded to each other.
Photochemically Induced Orthometalations. Isolation of (

Remark: Graphics omitted.

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) from RMn(CO)3[P(OPh)3]2(R=CH3 and H) and MeMn(CO)4P(OPh)3
Authors: Onaka Satoru , Kondo Yoshinori , Furuichi Nobuhiro
Published: July 2006

Photochemical reactions of RMn(CO)3L2 (R=H and CH3; L=P(OC6H5)3) and CH3Mn(CO)4L in benzene gave several kinds of orthometalated products, (Remark: Graphics omitted.) (x=0, 1, and 2). The reactions have been shown to proceed via ligand dissociation, CO and/or L, from the parent compounds and the resulting 16-electron intermediates activate a C–H bond of phenyl groups in triphenyl phosphite intramolecularly to yield orthometalated products. The results of photochemical reactions for MeMn(CO)3L2 and MeMn(CO)4L are compared with those of thermal reactions for these compounds. HMn(CO)4L was left intact by photochemical and thermal reactions.
Synthesis of 2-(4-Azulenyl)ethanamine Derivatives as a Nonbenzenoid Analog of Biogenic Amine
Authors: Kurokawa Shinji
Published: July 2006

2-(4-Azulenyl)ethanamine derivatives, nonbenzenoid analogs of the biologically active amine, were synthesized by the action of methyleneammonium salts on sodium 4-methylazulenide, sodium 4,6,8-trimethylazulenide, and sodium guaiazulenide. These compounds, as well as their hydrochlorides, were characterized by UV, IR, 1H NMR, 13C NMR, and MS data. The reaction of sodium guaiazulenide and N-ethylidenemethylamine also yielded the corresponding 2-(4-azulenyl)ethanamine derivatives, but the low yield of the product showed that the electrophilicity of azomethine carbon atom to 4-methylene carbanion was insufficient. The enzyme activity for some of those products was investigated. Negligible effect was found on prostaglandin 15-hydroxydehydrogenase, and considerable inhibition to cyclic AMP-phosphodiesterase, in vitro.
Synthetic Studies on the Validamycins. VII. Synthesis of Dl-2-Deoxyhydroxyvalidamine and Dl-2-Deoxyvalienamine
Authors: Ogawa Seiichiro , Ito Hiroyuki , Ogawa Takao , Iwasaki Shinichi , Suami Tetsuo
Published: July 2006

Synthesis of the 2-deoxy analogs of Dl-hydroxyvalidamine and Dl-valienamine starting from Dl-1,2-di-O-acetyl-(1,3,5/2)-5-bromo-3-bromomethyl-1,2-cyclohexanediol is described.
A Basic Study of the Amino Acid Residue in Protein. The Molecular Interaction Responsible for the Differentiation of Hydrocarbon Residues
Authors: Hiraki Yuji , Oda Toshihiko , Tai Akira
Published: July 2006

A pair of primary amines was competitively acylated with acid anhydride in water–dioxane mixed solvents. Based on the product distribution, the mode of differentiation of hydrocarbon residues in the competing substrates with a reagent was studied. In solvents with a low water content, where both reactants and products were completely soluble, no appreciable differentiation of the alkyl-chain length of alkylamines occurred. On the other hand, the differentiation of a phenyl group from an alkyl group occurred. From the dependency of the product distribution on the water content in reaction media, an attractive interaction induced by water was postulated between alkyl and phenyl groups, but no such interaction was observed between alkyl and alkyl groups. The differences in functions of the phenyl and alkyl groups in the differentiation process are discussed. In solvents with a very high water content, the acylation proceeded under heterogeneous conditions, since acid anhydrides became insoluble and provided an organic phase in the reaction mixture. In this case, the differentiation was controlled by the hydrophobicity of hydrocarbon residues of amines indexed by the partition coefficients of amines between the aqueous phase and the organic phase.
Ionic Composition of Micelles and the Dissolved State of the Mixed Surfactant Solutions of Calcium and Sodium Decyl Sulfates
Authors: Koshinuma Masakatsu
Published: July 2006

Single activities of the decyl sulfate (DeS−), the calcium (Ca2+), and the sodium (Na+) ions in mixed surfactant solutions of varying mole ratios (Rm=Ca(DeS)2/NaDeS) were obtained at 30±1 °C by means of three kinds of EMF cells with ion-exchange membranes or Na+-selective electrode. The results showed that with increasing concentrations above the cmc, the activity of the DeS− decreases gradually, while that of the Na+ increased linearly; the activity of the Ca2+ remained nearly constant in the solution of Rm=2, but it showed a minimum in the solutions of Rm=1, 0.5 and 0.2. From these activities, the counterion attachments of the Ca2+(rCa) and the Na+(rNa) and the degree of micellar charge (1−2rCa−rNa) were obtained. With increasing concentration, rCa diminished gradually and approached a constant value, while rNa and 1−2rCa−rNa changed reversely except in the solution of Rm=2 where they were nearly constant. The Ca2+ was bound preferentially to the micelle surface. The Na+, which almost diffused away for the solution of Rm=2, bound increasingly to lessen the electrical potential of the micelle as Rm decreased. The specific adsorption potentials and the electrical free energies of transfer of Ca2+ and Na+ from solution to micelle were calculated as 1.7 and −18.4 kJ mol−1, and 1.1 and −14.3 kJ mol−1 respectively at their cmcs. It was showed clearly that little dehydration from the counterion occured and the coulombic interaction played an important role in the counterion binding.
Reactions of NH Radicals. II. Photolysis of HN3 in the Presence of C2H6 at 313 nm
Authors: Kodama Sukeya
Published: July 2006

Photolysis of HN3 vapor with C2H6 was studied at 313 nm and 30 °C. The products are N2, H2, CH4, NH4N3, CH3NH2·HN3, C2H5NH2·HN3, CH3N3, and CH3CN. The quantum yields of these products were measured as a function of pressures of HN3 and C2H6, and the light intensity. The following mechanism for the main reactions was proposed: HN3+hν(313 nm)→N2+NH(a1Δ); NH(a1Δ)+HN3→2N2+2H (2a); NH(a1Δ)+HN3→NH2+N3 (2b); NH(a1Δ)+HN3→N2+N2H2* (2c); NH(a1Δ)+C2H6→C2H5NH2* (3); NH(a1Δ)+C2H6→NH(X3Σ−)+C2H6 (4); C2H5NH2*→CH3+CH2NH2 (5); C2H5NH2*→CH3CN+2H2 (6); C2H5NH2*+M→C2H5NH2+M (7). The rate constant ratios at 30 °C are: k3⁄k2=0.334; k4⁄k2=0.217; k6⁄k5=0.038. The values of k7⁄k5 for C2H6, HN3, CO2, and Xe are 36.5, 30.3, 29.0, and 14.5 dm3 mol−1, respectively. The values of k5=9.8×109 s−1, k6=3.7×108 s−1, τ (half life of C2H5NH2*)=6.8×10−11 s, η (collisional deactivation efficiency of C2H5NH2*)=1 for C2H6, HN3, and CO2, and η=0.60 for Xe were obtained by using the collision theory.
Reactions of NH Radicals. III. Photolysis of HN3 in the Presence of C2H4 at 313 nm
Authors: Kodama Sukeya
Published: July 2006

Photolysis of HN3 vapor in the presence of C2H4 was studied at 313 nm and 30 °C. The main products were N2, H2, CH4, C2H6, NH4N3, C2H5N·HN3 (salt of C2H5N (azomethines) with HN3), HCN, CH3CN, CH3N3, and C2H5N3. The quantum yields of these products were measured as a function of the light intensity and pressures of HN3 and C2H4. The following mechanism for the main reactions was infered: HN3+hν(313 nm)→NH(a1Δ)+N2; NH(a1Δ)+HN3→2N2+2H (2a); NH(a1Δ)+HN3→NH2+N3 (2b); NH(a1Δ)+HN3→N2+N2H2* (2c); NH(a1Δ)+C2H4→C2H5N* (aziridine and vinylamine) (3); C2H5N*→CH3+CH2N (4); C2H5N*→H2+CH3CN (5); C2H5N*→H+C2H4N (6); C2H5N*→C2H3+NH2 (7). The rate constant ratios at 30 °C are: k3⁄k2=1.64; k5⁄k4=0.102; k6⁄k4=0.564; k7⁄k4=0.734. The collisional deactivation from NH(a1Δ) to NH(X3Σ−) by C2H4 was not found. The lifetime of C2H5N* is much shorter than 6.8×10−11 s for C2H5NH2*(←NH(a1Δ)+C2H6). The relative and absolute rates for the reactions of NH(a1Δ) with HN3, Xe, C2H6, and C2H4 are discussed.
Kinetics of Gas Phase Addition Reactions of Trichlorosilyl Radicals. VIII. Reinvestigation of Addition to Ethylene
Authors: Dohmaru Takaaki , Nagata Yoshio
Published: July 2006

The addition of ·SiCl3 radicals to ethylene has been reinvestigated using a large conversion method. The amended values are log(k3⁄k5)=−0.17±0.05−(0.80±0.10) kcal mol−1/2.303 RT and log{k−5⁄k6(mol cm−3)}=3.4±0.3−(22.5±0.7) kcal mol−1/2.303 RT where the reactions involved are ·SiCl3+CH3COCH3\overset3→(CH3)2\dotCOSiCl3, ·SiCl3+C2H4\overset5\underset−5\ightleftarrows·CH2CH2SiCl3 and ·CH2CH2SiCl3+HSiCl3\overset6→C2H5SiCl3+·SiCl3.
Circular Dichroism Spectra and Absolute Configurations of fac(NH3)-[Co(a)(gly)(NH3)3]n+-type Complexes
Authors: Fujinami Shuhei , Hattori Akihiko , Shibata Muraji
Published: July 2006

Four complexes [Co(a)(gly)(NH3)3]+ (a=CN−, NO2−, NCS−, and N3−) and a related [Co(NO2)(β-ala)(NH3)3]+ complex have been prepared; they were characterized by the absorption spectra in the ultraviolet region. The fac(NH3) isomers of these complexes have been optically resolved by column chromatography. The CD spectra of fac(NH3)-[Co(H2O)(gly)(NH3)3]2+ and fac(NH3)-[Co(H2O)(β-ala)(NH3)3]2+ have also been measured. The absolute configurations of the fac(NH3) isomers have been determined by referring to the CD spectrum of fac(NH3)-(−)589[Co(NO2)(gly)(NH3)3]ClO4 which had been subjected to an X-ray analysis. Each isomer has exhibited a dominant Cotton peak at ca. 20000 cm−1 in the first absorption band region. The peak has been assigned to the electronic transition component which arises in the plane containing the glycinate chelate. The CD spectra fac(NH3)-[Co(a)(gly)(NH3)3]+ have been compared with those of the corresponding [Co(a)(gly)(1,4,7-triazacyclononane)]+ complexes, and the sources of the optical activities in these complexes have been investigated.
Reactivity of Aromatic o-Hydroxy Oximes. I. Synthesis and Aminolysis of Acylglycine Esters of Aromatic o-Hydroxy Oximes
Authors: Hayashi Ikuo , Ogihara Keizo , Shimizu Kiyoshi
Published: July 2006

Active esters (1) of glycine with o-hydroxybenzaldehyde oxime, o-hydroxyacetophenone oxime, o-hydroxybenzophenone oxime, and their 5-Cl and 5-NO2 derivatives were prepared by several methods. For aminolysis with benzylamine, esters 1 show higher reactivity than similar esters containing no hydroxyl group in the ortho position. It is suggested that esters 1 forms an intramolecular hydrogen bond between the hydrogen of the hydroxyl group at the ortho position and the hydroxyimino nitrogen so as to have its carbonyl group activated for the aminolysis; this mechanism of activation seems to be a sort of “intramolecular acid-catalysis.” Among the series of esters 1, esters of o-hydroxybenzaldehyde oxime and its 5-Cl and 5-NO2 derivatives are most reactive in the aminolysis. The reactivity of esters 1 is also discussed in relation to pKa values of aromatic o-hydroxy oximes.
The Ruthenium Complex Catalyzed N-Heterocyclization of Aminoarenes to Quinoline Derivatives Using Allylic Alcohols and Aliphatic Aldehydes
Authors: Watanabe Yoshihisa , Tsuji Yasushi , Ohsugi Yukihiro , Shida Jun
Published: July 2006

Aminoarenes reacted with 2-propen-1-ol and 2-buten-1-ol at 180 °C to give quinoline derivatives in fairly good yields in the presence of a catalytic amount of a ruthenium complex. Dichlorotris(triphenylphosphine)ruthenium was the most effective catalyst. The aminoarenes with electron-releasing groups favored the formation of the quinolines. The N-heterocyclization also proceeded when aliphatic aldehydes were used in place of the allylic alcohols. The employment of allylic alcohols gave, however, higher yields in several cases. The reaction involves the isomerization of the allylic alcohols to the corresponding aldehydes. The aldehydes reacted with aminoarenes to give Schiff-base dimers which were then cyclized in the presence of the ruthenium complex to the quinolines. As a key intermediate in the reaction, the ortho-metallated species has been proposed.
The Reaction of Olefins with a Mixture of Iodine and Mercury(II) Thiocyanate. Predominant Formation of vic-Iodo(isothiocyanato)alkanes
Authors: Watanabe Nanao , Uemura Sakae , Okano Masaya
Published: July 2006

Treatment of olefins with a mixture of iodine and mercury(II) thiocyanate in benzene or diethyl ether gives vic-iodo(isothiocyanato)alkanes and vic-iodo(thiocyanato)alkanes in a high yield, the former being predominant. Similar results were obtained by using silver(I) and thallium(I) thiocyanates, though both the yield and the selectivity are slightly lower. By use of potassium thiocyanate and copper(I) isothiocyanate in place of mercury(II) thiocyanate, β-iodo thiocyanates were mainly formed. A reaction scheme involving initial formation of an iodonium ion from olefin and ISCN (formed in situ) and a subsequent attack of complex anion I(SCN)2− has been proposed to account for this predominant formation of β-iodo isothiocyanates.
Effect of Multiple Field Assistance with Reversed Micelles on the Decarboxylation of 6-Nitro-1,2-benzisoxazole-3-carboxylate
Authors: Sunamoto Junzo , Iwamoto Kiyoshi , Nagamatsu Shinichi , Kondo Hiroki
Published: July 2006

Decarboxylation reaction of 6-nitro-1,2-benzisoxazole-3-carboxylate (1) in cationic and anionic reversed micelles has been investigated with particular attention to the microenvironmental effect, such as microviscosity, micropolarity, and microactivity, in the specific and restricted reaction field as provided by reversed micelles. In 0.20 M CTAC/0.32 M H2O/CHCl3 reversed micelles, the reaction was accelerated about 1300-fold compared with that in bulk aqueous solution. Of various surfactant aggregate systems such as aqueous micelle, bilayer, and reversed micelle, the cationic reversed micelle could provide the most effective reaction field for the present decarboxylation reaction. This reaction is never accelerated in an anionic aqueous micelle. However, in the anionic AOT reversed micelle, the reaction was apparently accelerated by both lowering the micropolarity and increasing the microviscosity around the substrate. The unique rate enhancement for the decarboxylation reaction of 1 provided by reversed micelles was interpreted in terms of the “multiple field assistance.”
Free Radical Chain Reaction of Allylic Tin Compounds with Organic Halides Involving SH′ Process
Authors: Migita Toshihiko , Nagai Kazukiyo , Kosugi Masanori
Published: July 2006

Negatively substituted halomethanes were allylated easily by allyltin compounds via radical chain reaction involving SH′ process. Aryl, aralkyl, and alkyl halides underwent similar chain reactions only when the tin compound was charged in excessive amounts.
N,N′-Carbonyldi[1,2-benzisoxazol-3(2H)-one]: New, Reactive Condensing Agent
Authors: Ueda Mitsuru , Oikawa Hideaki , Kawaharasaki Naomi , Imai Yoshio
Published: July 2006

A new condensing agent, N,N′-carbonyldi[1,2-benzisoxazol-3(2H)-one] (6), was readily prepared by the reaction of 1,2-benzisoxazol-3-ol and trichloromethyl chloroformate in toluene. The condensing agent 6 was shown to be very useful for the preparation of amides, esters, and dipeptides under mild conditions. A successful polyamide synthesis by one-pot polycondensation of isophthalic acid with diamines using 6 was also described.
Thermal Studies of Nickel(II) Hydrazine Complexes in Solid State
Authors: Banerjee Bijoy , Biswas Prasanta Kumar , Ray Chaudhuri Nirmalendu
Published: July 2006

Two bis(hydrazine)nickel(II) fluoro complexes of the type [NiL2F2]·H2O, where L=NH2NH2 have been synthesized. Besides these, [NiL2.5(H2O)2]F2·0.5H2O and [NiL2.5F2]·2H2O have also been synthesized. Thermal investigations of these complexes have been carried out. Four tris(hydrazine)nickel(II) chloride and four tris(hydrazine)nickel(II) bromide complexes have been prepared and their thermal investigations have been done. Two bis(hydrazine) thiocyanato complexes have also been prepared and their thermal studies have also been carried out. These nickel(II) hydrazine complexes have been found to decompose through several complex species as intermediates. All these intermediates as well as the parent complexes have been characterized by elemental analyses, color, magnetic moment, electronic spectra (mull), and IR spectra. X-Ray powder diffraction pattern of two tris(hydrazine)nickel(II) bromide complexes have been obtained. The probable mechanistic paths for each step of decomposition have been proposed.
Carbon Monoxide Absorption by Solutions of Aluminium Copper(I) Chloride in Various Aromatic Solvents
Authors: Hirai Hidefumi , Nakamura Masahiro , Komiyama Makoto
Published: July 2006

Carbon monoxide absorbents composed of aluminium copper(I) chloride and various aromatic solvents are prepared, and their absorbing capacities are determined. The plot of the equilibrium molar ratio of the absorbed carbon monoxide to AlCuCl4  vs. the ionization potential of the aromatic solvent indicates that both electronic and steric factors are important in the molecular complex formation between AlCuCl4 and aromatic solvent molecules.
A Convenient Method for the Synthesis of Acyclic Ketones. Synthesis of Sex Pheromone of Douglas Fir Tussock Moth
Authors: Murata Yasue , Inomata Katsuhiko , Kinoshita Hideki , Kotake Hiroshi
Published: July 2006

(α-Alkyl-α-methylthio)alkyl p-tolyl sulfones derived from the reaction of α-alkylated alkyl p-tolyl sulfones with dimethyl disulfide could be easily hydrolyzed by CuCl2–SiO2 to give the corresponding ketones in fairly good yields. This method was applied to the synthesis of Douglas Fir Tussock Moth Pheromone.
Cation Transport through Liquid Membranes Facilitated by Crown Ether-modified Poly(iminoethylene)s
Authors: Anzai Jun-ichi , Sakata Yoko , Suzuki Yasuhiro , Ueno Akihiko , Osa Tetsuo
Published: July 2006

Poly(iminoethylene)s containing benzo-15-crown-5 moieties as pendant groups can transport Rb+ cation more effectively than the other alkali cations through an organic liquid membrane. The transport selectivities of the polymers diminish drastically with decreasing crown ether content in the polymer chain.
ESR Studies of Bunsen-type Methane-Air Flames. II. The Effects of the Addition of Halogenated Compounds to the Secondary Air on the Hadrogen Atoms in the Flame
Authors: Noda Shoji , Fujimoto Susumu , Claesson Ola , Yoshida Hiroshi
Published: July 2006

Hydrogen atoms in a methane-air Bunsen-type flame were detected by the flame-in-cavity ESR method. The addition of a halogenated compound to the secondary air was found to reduce the H-atom concentration linearly with an increase in the additive concentration. The eight halogenated compounds examined showed an increased effectiveness in scavenging H atoms in this order; HCl<CF2Cl2<CHCl3<CH3Cl<CH2Cl2<CFCl3<CCl4<CH3Br. This chemical effect of the halogenated compounds on the combustion reactions agrees well with the inhibitor index for these compounds.
Ultraviolet Photoelectron Spectra of α- and β-Polymorphs of Copper Phthalocyanine
Authors: Chen Shang Xian , Seki Kazuhiko , Inokuchi Hiroo , Shi Zurong , Qian Renyuan
Published: July 2006

The ultraviolet photoelectron spectra have been measured for α- and β-forms of copper phthalocyanine at 183 °C, to investigate the correlation of photoemissive behavior with crystal structure. Their threshold ionization potentials were 4.88 and 4.62 eV, with polarization energy of 1.27 and 1.53 eV, respectively. This difference could not be explained by calculation with point charge-point dipole approximation, but calculation with distributed charge on the cation and distributed induced dipoles on the nearest neighbor two molecules gave semi-quantitative agreement with the experimental findings.
Phosphorescence Spectra of p-Dichlorobenzene in Various Matrices at 1.4 K
Authors: Kinoshita Minoru , Goto Narito , Iwasaki Noriko
Published: July 2006

The phosphorescence spectra of p-dichlorobenzene have been obtained at 1.4 K in various hosts; benzene, p-xylene, p-dichlorobenzene, p-dichlorobenzene-d4, and p-dibromobenzene. The long progressions in the b2g, C–Cl bending vibration are indicative of a molecular distortion in the out-of-plane direction. With the aid of the technique of optical detection of zero-field magnetic resonance, the intense 1580 cm−1 band previously ascribed to the ag, ν8a vibration is found to be due to the b3g, ν8h vibration. The appearance of the b3g band with strong intensity suggests a possibility of an additional in-plane distortion of phosphorescent p-dichlorobenzene.
The Synthesis, Properties, and Structure of Bis(N,N-dimethylacetamide)tris(O,O′-diisopropyl dithiophosphato)lanthanum(III)
Authors: Nagai Kiyofumi , Sato Yoshiyuki , Kondo Satoshi , Ouchi Akira
Published: July 2006

The new complex indicated in the title has been synthesized, and its crystal and molecular structure has been determined by the X-ray diffraction method. The crystal was triclinic; space group P\bar1, Z=2, a=23.071(9), b=11.060(11), c=10.793(13) Å, α=120.0(1), β=97.2(2), γ=88.9(2)°. The final R value for 5969 reflections is 0.047. The central lanthanum(III) atom is an octa-coordination and in a dodecahedron geometry, being coordinated with six sulfur atoms of three O,O′-diisopropyl dithiophosphate ligands (iPr2dtp), which span at three m edges, and with two oxygen atoms of both the N,N-dimethylacetamide ligands (dma) at both ends of the remaining m edge. The other [Ln(iPr2dtp)3L2]-type complexes, where Ln=La or Nd; L=dma or N,N-dimethylformamide, have also been obtained. The P=S double bond of the iPr2dtp ligand in the title complex is almost completely delocalized.
Determination of Ethylenediaminetetraacetic Acid and Nitrilotriacetic Acid as Their Iron(III)-Complexes by Reversed Phase High Performance Liquid Chromatography
Authors: Yamaguchi Akihiro , Rajput Allah Rakha , Ohzeki Kunio , Kambara Tomihito
Published: July 2006

The iron(III) complexes with ethylenediaminetetraacetic acid (EDTA, H4edta) and nitrilotriacetic acid (NTA, H3nta) were separated by the ion-association reversed phase high performance liquid chromatography. The retention behavior of iron(III)–nta complex on the column (4.6 mm i.d., 25 cm long) packed with ZORBAX-ODS was seriously affected by the pH of eluent composed of phosphate buffer solution containing tetrabutylammonium bromide and acetonitrile. A mixture of edta and nta in a synthetic sample solution containing the commonly present metal ions was converted to the corresponding iron(III) complexes and determined successfully by the present method.
The Coagulated Ion-exchanger Colorimetry of Cobalt(II)–Thiocyanate Complex
Authors: Suzuki Kin-ya , Ohzeki Kunio , Kambara Tomihito
Published: July 2006

The coagulated ion-exchanger colorimetry was applied to the determination of a trace amount of cobalt(II). Cobalt(II)–thiocyanate complex was fixed by a batch method on the coagulated material composed of fine particles of anion and cation exchangers. The coagulated material was collected on a filter paper and a colored thin layer was prepared. The coloration of the compound was further intensified by dipping the thin layer in a concentrated thiocyanate solution, and the absorbance was determined by a densitometer. The calibration curve showed a good linearity in the range of 1–15 μg of cobalt(II). Iron(III) and copper(II) showed interfering coloration, but these ions were effectively masked by the addition of fluoride and egta, respectively. Zinc(II) gave seriously negative error.
Cooperativity in the Binding of Sodium Dodecyl Sulfate to Amylose
Authors: Yamamoto Masako , Sano Takayuki , Harada Shoji , Yasunaga Tatsuya
Published: July 2006

The binding isotherm of sodium dodecyl sulfate to amylose was potentiometrically investigated by using amyloses of various degrees of polymerization from 32 to 1100. From the Scatchard plots, the binding was found to be cooperative for the amyloses of DP≥76 and Langmuir type for those of DP≤57. By analogous experiments using a series of sodium alkyl sulfates, it was clarified that (1) eight carbon atoms of surfactant are required for the complexation and (2) more than twelve carbon atoms of surfactant are required for the cooperative binding. Thus, the amylose has an interrupted helical structure in solution and the cooperativity arises from the hydrophobic interaction between the surfactants included partly in the helic of amylose.
The Reaction of Sulfur Dioxide with Thiols Catalyzed by Boron Trifluoride Etherate. Evidence for a Possible Intervention of Dithiosulfite as a Reaction Intermediate
Authors: Akiyama Fuminori
Published: July 2006

The reaction of sulfur dioxide (SO2) with 1-propanethiol (NPT), 2-propanethiol (IPT), or 2-methyl-2-propanethiol (TBT) catalyzed by boron trifluoride ethrate (BF3OEt2) was investigated. The ratios of dialkyl trisulfide to dialkyl disulfide obtained (RSSSR/RSSR) at an early stage of the reaction were larger than 1 for the reaction of TBT and less than 1 for the reaction of NPT or IPT. The reaction of dithiosulfites with BF3OEt2 in the presence or absence of thiol was investigated. From a consideration of the similarity of the composition of the sulfides formed in the reaction of dithiosulfites with BF3OEt2 to those in the reaction of SO2 with thiol in the presence of BF3OEt2, the possibility of the intervention of dithiosulfite as a reaction intermediate in the reaction of SO2 with thiol was discussed.