bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Synthesis of Cyclic α-Amino Acids. I
Authors: Umezawa Sumio , Kinoshita Mitsuhiro , Yanagisawa Hiroaki 
Published: July 2006

Abstract
The reactions of α, β-unsaturated α-nitroesters with dienes produced cyclic α-nitroesters. In all cases, a mixture of diastereoisomers was obtained. Catalytic hydrogenation, followed by hydrolysis, gave a number of cyclic α-amino acids which are closely related to natural terpenes. The NMR spectra of some of these compounds were useful in making structural assignments.
Copolymerization of Cyclic Olefins, Trimethylethylene and Tetramethylethylene with Acrylonitrile
Authors: Yasufuku Katsutoshi , Nozakura Shun’ichi , Murahashi Shunsuke 
Published: July 2006

Abstract
The radical copolymerizations of cyclopentene, cyclohexene, cycloheptene, cyclooctene, trimethyl-, and tetramethyl-ethylene with acrylonitrile (AN, M1) were carried out, and the reactivities of these monomers toward the AN radical (1/r1) were found to be as follows: cyclopentene, 0.21; cyclohexene, 0.13; cycloheptene, 0.15; cyclooctene, 0.35; trimethylethylene, 0.37, and tetramethylethylene, 0.25. The reactivity of these internal olefins in radical polymerization was discussed.
Studies on Geometric Isomerism by Nuclear Magnetic Resonance. IV. Structure of α-Cyano-β-amino-β-alkylacrylic Esters
Authors: Hayashi Toshio , Hori Isaburo , Baba Hideo , Midorikawa Hiroshi 
Published: July 2006

Abstract
The NMR spectra of α-cyano-β-amino-β-alkylacrylic esters prepared from α-cyano-β-methoxy-β-alkylacrylic esters and simple amines have been studied. It has been found that these aminoesters, in a variety of solvents, are all present in an intramolecular hydrogen-bonded enamine form with a chelate ring.
The Chlorofluorination of Ethylene, Ethane, Fluoroethylene and Methane
Authors: Nagase Shunji , Baba Hajime , Abe Takashi 
Published: July 2006

Abstract
This novel electrochemical chlorofluorination involves the passage of each of the title materials, together with chlorine, through liquid hydrogen fluoride containing sodium fluoride. Chlorofluoroethanes were produced directly from ethylene, ethane, and fluoroethylene, while chlorofluoromethanes were produced directly from methane. Carbon tetrachloride, chloroform, and phosgene could also be used as a source of chlorine for the chlorofluorination reaction. Thionyl and sulfuryl chlorides, and sulfur mono- and di-chlorides did not act as chlorinating reagents.
Studies of the Alkaline Earth Metal Complexes in Various Solutions. II. Beryllium(II) Complexes with Sulfate and Oxalate in 1 m Na(ClO4)
Authors: Sekine Tatsuya , Sakairi Mitsuo 
Published: July 2006

Abstract
The complex formation of beryllium (II) with sulfate and oxalate ions in 1 m Na(ClO4) at 25°C has been studied by a liquid-liquid distribution method. The radioactive tracer beryllium-7 at very low concentration was used in conjunction with thenoyltrifluoroacetone in methylisobutylketone. The stability constants of the beryllium complexes were determined graphically from the distribution data by a curve-fitting method. The data seemed to be explained by the formation of the following complex species;
βn=[BeLn2–2n]⁄[Be2+][L2−]n,
where logβ2=1.78 and logβ3=2.08 for sulfate and logβ1=3.55 and logβ2=5.40 for oxalate. The formation of the primary sulfate complex, BeSO4, or the tertiary oxalate complex, Be(C2O42−)34−, was not concluded within the ligand concentration region studied.
The Crystal Structure of p, p′-Dichlorodiphenoxy-1, 2-ethane
Authors: Yasuoka Noritake , Ando Tadanao , Kuribayashi Shunsuke 
Published: July 2006

Abstract
Crystals of p, p’-dichlorodiphenoxy-1,2-ethane are monoclinic; their space group is P2/c, and they have 4 molecules in the cell with dimensions of:
a=12.79, b=9.89, c=10.37Å; β=98.2°
Two crystallographically-independent molecules, which are slightly different in conformation, are located on the two-fold axis of the crystal. The OCH2CH2O groups are of the gauche form.
The Crystal Structure of 1,2-Diphenoxyethane
Authors: Yasuoka Noritake , Ando Tadanao , Kuriyabashi Shunsuke 
Published: July 2006

Abstract
1,2-Diphenoxyethane crystallizes in two forms, flake-shaped and prismatic. The crystal and molecular structures of the prismatic crystals were determined and described. The orthorhombic unit cell dimensions are: a=34.74, b=12.04, and c=5.58 Å. The space group is Fdd2. The molecule has the symmetry of a two-fold axis, and the OCH2CH2O group exists in a gauche conformation with an internal rotation angle of 66.9°.
Syntheses and Properties of Some Thio Derivatives of Acetylacetonato-nickel(II)
Authors: Ouchi Akira , Hyodo Mitsutoshi , Takahashi Yoshiaki 
Published: July 2006

Abstract
Derivatives of acetylacetonato-nickel(II) in which the coordinating oxygen is replaced by sulfur to various extents have been isolated by the reaction between nickel(II) acetylacetonate and hydrogen sulfide in an ethanolic solution, using hydrogen chloride as the catalyst. These compounds are soluble in organic solvents, such as benzene, acetone, or carbon tetrachloride, but can hardly be dissolved in water. The proton magnetic resonance spectra indicate that the proton of the methyl group attached to the C=S carbon gives greater chemical shifts than that of the methyl group attached to the C=O carbon. The infrared spectra of these compounds are discussed with particular reference to the C=S stretching bands. The electronic spectra of these compounds and the Hückel LCAO-MO calculation of bis dithio compounds are also compared.
Synthetic Studies of Bacitracin. V. Synthesis of Thiazoline Peptides from Cysteine Peptides by Dehydration Procedure
Authors: Hirotsu Yoshihiro , Shiba Tetsuo , Kaneko Takeo 
Published: July 2006

Abstract
Synthesis of thiazoline peptide from cysteine peptide by dehydration with hydrochloric acid in non-aqueous solvent was investigated. By this method, ethyl 2-benzyloxycarbonylaminomethyl-R-Δ2-thiazoline-4-carboxylate and 2 - benzyloxycarbonylaminomethyl-R-Δ2-thiazoline-4-carbonyl-l-leucine ethyl ester were prepared and isolated in pure states. This synthetic method could give a promising route to a total synthesis of bacitracin A. However, the cysteine residue in the latter thiazoline peptide ester was found to be easily racemized under the basic condition.
Structure of Busch’s Endo-thiatriazolines
Authors: Ohta Masaki , Kato Hiroshi , Kaneko Takashi 
Published: July 2006

Abstract
The methods of preparing 2,4-dihydro-1,3,4-thiadiazole-2-thiones are discussed. The structure of the reaction products of these compounds or their methiodides with amines is determined to be 1,3-dihydro-1,2,4-triazole-3-thiones.
Medium-Sized Cyclophanes. III. The Nitration Reaction of [2.2]Metacyclophane with Benzoyl Nitrate
Authors: Fujimoto Meiko , Sato Takeo , Hata Kazuo 
Published: July 2006

Abstract
The nitration reaction of [2.2]metacyclophane was carried out using dilute nitric acid or benzoyl nitrate under various conditions. Dilute nitric acid afforded 2-nitro-4, 5, 9, 10-tetrahydro-pyrene as the sole product, confirming Allinger’s original experiments, whereas benzoyl nitrate furnished a complex mixture consisting of 4, 5, 9, 10-tetrahydropyrene, 4, 5-dihydropyrene and pyrene, together with the nitration product. A series of experiments established that 4, 5, 9, 10-tetrahydropyrene, which was formed by the 1, 4-elimination reaction of Allinger’s intermediate, was the initial product of the reaction. Two competitive reactions, nitration and dehydrogenation reactions of the tetrahydropyrene, were assumed to be occurring, thus accounting for the experimental results.
The Infrared Study of the Adsorption of Ethanol on Alumina
Authors: Arai Hiromichi , Saito Yasukazu , Yoneda Yukio 
Published: July 2006

Abstract
The structure of ethanol adsorbed on alumina has been studied by means of infrared spec-troscopy. At room temperature physically-adsorbed ethanol was observed, but it was completely removed by evacuation at 70°C for 2 hr. On the contrary, another adsorbed species remained after long evacuation at 70°C; it was identified as a surface ethoxide (C2H5OAl&lt;). The concentration of the surface ethoxide on alumina had a linear correlation with the intensity of the CH3 symmetric deformation band at 1387 cm−1. The molar absorption coefficient of the band at 1387 cm−1 decreased parallel with 1/T at a higher temperature. The number of adsorption sites was calculated as 2.1×1014 sites/cm2 when the ethanol was exposed at 70°C to an alumina catalyst which had been evacuated at 550°C for 5 hr.
Mass Spectrometric Studies of Metal Acetylacetonates
Authors: Sasaki Shin-ichi , Itagaki Yasuhiro , Kurokawa Tadashi , Nakanishi Koji , Kasahara Akira 
Published: July 2006

Abstract
The mass spectra of fifteen metal acetylacetonates measured under the electron impact with 70 eV energies are reported. The acetylacetonates can be divided into three groups, A, B, and C, according to their stability in mass spectrometeric measurements. When the electronegativity of the central metal atom is 1.5—1.6, the complexes show abundant molecular ion peaks (group A); when the electronegativity is 1.6—1.8, no molecular ion appears and the M-L cations show as the highest mass (group B); when the electronegativity is greater than 1.8, there are no peaks arising from fragments containing the metal, only acetylacetone peaks being apparent (group C). Furthermore, the mass spectra of hexafluoroacetylacetone and its copper complex were also measured.
High Frequency Inductance Manometer for Gaseous Reaction Studies
Authors: Yasumori Iwao , Ohno Seigo , Miyazaki Eizo 
Published: July 2006

Abstract
A corrosion-free manometer which employs a variable inductor as a transducer has been devised. Its main part consists of a pair of small coils and a glass Bourdon bulb on which a thin aluminum disc is so attached as to be located between the coils. A manometer constructed as an example has the following characteristics: measurable (linear) range of pressure difference, 0–20 mmHg; minimum detectable pressure difference, 7×10−2 mmHg; temperature coefficient of zero-point drift, 0.2% of the full scale (20 mmHg) per degree; negligible temperature coefficient of output voltage per unit of pressure difference; limit of response time, 0.6 sec (under atmospheric pressure)–4 sec (1.1×10−3 mmHg). It is possible to extend the measurable range by changing the rigidity of the Bourdon bulb. From these results, it may be concluded that the manometer is useful in following and recording changes which have half-decay times of longer than a few seconds. When the manometer was applied to the study of the catalytic decomposition of formaldehyde on nickel wire, its usefulness was proved.
The Dissociation Phenomena of o-Phenol- and m-Chloro-o-phenolazochromotropic Acids and the Formation Constants of Magnesium and Calcium Chelates
Authors: Nakashima Susumu , Miyata Haruo , Tôei Kyoji 
Published: July 2006

Abstract
The acid dissociation constants of o-phenol-, m-chloro-o-phenol- and o-anisolazochromotropic acids have been measured by potentiometric titration. The measurements have been carried out at 25.0±0.1°C and μ=0.10 (by KNO3). From these constants, the dissociation of the hydroxyl groups in the reagents has been discussed. The phenolic hydroxyl group was first dissociated, and then one of the naphtholic hydroxyl groups; the other naphtholic group was not dissociated under ordinary experimental conditions. The pKa1 and pKa2 values were 7.60 and 10.60 for o-phenolazochromotropic acid, and 7.56 and 10.35 for m-chloro-o-phenolazochromotropic acid. o-Phenol- and m-chloro-o-phenolazochromotropic acids formed 1 : 1 chelates with calcium and magnesium. The formation constants were measured potentiometrically; the logK’s for calcium were 5.01 and 5.22, and for magnesium, 6.15 and 6.22.
Studies of Peptide Antibiotics. VIII. Synthesis of Gly4,4′-gramicidin S
Authors: Nagata Reiko , Waki Michinori , Kondo Michio , Aoyagi Haruhiko , Kato Tetsuo , Makisumi Satoru , Izumiya Nobuo 
Published: July 2006

Abstract
Gly4,4′-gramicidin S dihydrochloride, cyclo-(l-valyl-l-ornithyl-l-leucylglycyl-l-prolyl)2·2HCl, which is an analog of gramicidin S, was synthesized for the purpose of comparing its antibacterial activity with that of gramicidin S. The cyclization reaction via the linear decapeptide active ester or via the linear pentapeptide active ester yielded the same cyclic benzyloxycarbonyl-substituted decapeptide; this was then converted to Gly4,4′-gramicidin S dihydrochloride by hydrogenolysis. The effect of the Gly4,4′-gramicidin S on bacterial growth was tested; the peptide exhibited weak antibacterial activity against Bacillus Subtilis.
Glass Transition Temperature and Isothermal Volume Change of Selenium
Authors: Hamada Shuichi , Sato Tadao , Shirai Toshiaki 
Published: July 2006

Abstract
The viscoelastic behavior of selenium and of partially-chlorinated selenium was studied by the dilatometric method. The glass transition temperature, Tg, of selenium was determined to be 32.0°C at a cooling rate of 0.2°C/min. The glass transition temperature decreased linearly with the reciprocal of the average chain length of selenium. The chain length was calculated using the degree of chlorination. An abrupt increase in Tg was observed at a chlorine content of about 0.013%. The volume-time curves obtained by the determination of the volume of selenium in the neighborhood of Tg were superposed on each other by sliding them along the abscissa. The values of the shift factor and of Tg fit well in Williams, Landel and Ferry’s equation. The parameters in the WLF equation, C1g and C2g, of selenium were calculated to be 6.86 and 28.6 respectively. Both the parameters increased with an increase in the chlorine content up to 0.0125%, and reached the values of usual polymers above 0.0125%. The WLF fg value of selenium was calculated to be 6.33×10−2. This value decreased with an increase in the chlorine content, and reached the universal value of usual polymers (2.5×10−2) when the chlorine content was more than 0.0125%. The chlorine content corresponds to 0.0125% when all the radicals at both ends of the linear chain molecules of selenium have been used in forming bonds with chlorine atoms. Therefore, it may be concluded that the existence of radicals at the molecular ends of selenium chains brings about an augmentation of the fraction of the free volume at Tg.
Synthetic Studies of the Flavone Derivatives. VII. The Synthesis of Jaceidin
Authors: Fukui Kenji , Matsumoto Takashi , Nakamura Shigehiro , Nakayama Mitsuru , Horie Tokunaru 
Published: July 2006

Abstract
The Hoesch reaction of iretol with methoxyacetonitrile yielded 2,4,6-trihydroxy-3,ω-dimethoxyacetophenone. According to the Allan-Robinson flavone synthesis with O-benzylvanillic anhydride, the acetophenone afforded 4′-benzyloxy-5,7-dihydroxy-3,3′,6-trimethoxyflavone. The catalytic debenzylation of the flavone gave jaceidin, 4′,5,7-trihydroxy-3,3′,6-trimethoxyflavone, which had previously been isolated from Centaurea species. Its triethyl ether was prepared from 3,5-diethoxy-4-methoxyphenol via the corresponding acetophenone, followed by the abovementioned flavone synthesis with O-ethylvanillic anhydride. The ultraviolet spectra of these flavones will also be reported.
The Polarographic Behavior of Aliphatic Aldehydes in Buffer Solutions Containing o-Phenylenediamine
Authors: Wasa Tamotsu , Musha Sôichirô 
Published: July 2006

Abstract
Formaldehyde (I), acetaldehyde (II), propionaldehyde (III), n-butyraldehyde (IV), n-caproaldehyde (V), and n-octaldehyde (VI) condense with o-phenylenediamine (OPD) to yield products, each of which gives a single, irreversible but well-defined oxidation wave (E1⁄2 vs. SCE at pH 8.0: −0.240 V for I, −0.242 V for II, −0.263 V for III, −0.290 V for IV, −0.316 V for V, and −0.338 V for VI). From these findings, it has been deduced that the condensation products of aldehydes with OPD would be benzimidazoline derivatives, which would be oxidized to benzimidazole derivatives at the dropping mercury electrode. Linear relations between the limiting currents of the condensation products with OPD and the concentrations of aldehydes [(1–20)×10−4 m], except for I, were obtained under the following conditions: (pH, 6–8(pHi max); the concentration of OPD, 2×10−2 m; the temperature, 25°C; and the condensation time, 15–60 min. The method was then applied practically in the determination of the purity of a commercial product of II and the quantity of II in the presence of glyoxal.
Intrachain Force Field and Normal Vibrations of Polyethylene Glycol
Authors: Matsuura Hiroatsu , Miyazawa Tatsuo 
Published: July 2006

Abstract
Normal vibrations of polyethylene glycol and the perdeuterated species were treated. Intrachain force field was expressed in terms of local-symmetry coordinates. Force constants were adjusted by the method of least squares, with reference to observed infrared and Raman frequencies. A set of force constants was obtained, which reproduces the observed frequencies with an r. m. s. deviation of 0.9%. The values of the force constants thus refined were discussed in comparison with corresponding values of related molecules. Vibrational assignments of the observed infrared absorption bands and Raman lines were revised on the basis of potential-energy distributions refined in the present treatment.
The Chromium(III) Complexes with Ammoniaisopropionicdiacetic Acid
Authors: Uehara Akira , Kyuno Eishin , Tsuchiya Ryokichi 
Published: July 2006

Abstract
A new chelating agent—ammoniaisopropionicdiacetic acid (abbreviated as AIPDA), one of the derivatives of ammoniatriacetic acid, was prepared. Also, the following chromium(III) complexes containing AIPDA as a ligand were newly prepared: NH4[Cr(OH)(aipda)(H2O)]·4H2O (purple) (I), NH4[Cr(OH)(aipda)(H2O)2]·2H2O (green) (II), [Cr(aipda)(o-phen)]·2H2O (brown) (III), [Cr(aipda)(bipy)]·3H2O (brown) (IV), [Cr(aipda)(l-pn)] (pink) (V), [Cr(aipda)-(py)2] (Pink) (VI) and NH4[Cr(OH)(aipda)(py)]·2H2O (reddish purple) (VII), where apipda, o-phen, bipy, l-pn and py are the abbreviations of the ammoniaisopropionatediacetate ion, o-phenanthroline, 2,2′-bipyridyl, l-propylenediamine and pyridine respectively. On the basis of the chemical and thermal analyses and the measurements of the electronic absorption spectra, the reflection spectra, and the IR spectra, it was found that, in these complexes, AIPDA can behave as a terdentate or a quadridentate ligand to chromium(III), but the 1 : 2 Cr(III) AIPDA complex like the corresponding ATA one could not be obtained because of the steric hindrance resulting from the introduction of a methyl group into ATA. Further information on the conductivities in an aqueous solution and the reflection spectra suggests that V and VI are gradually aquated. The properties of the AIPDA complexes obtained in the present study were compared with those of ammoniatriacetic acid and those of ammoniapropionicdiacetic acid complexes.
Use of a Hanging Mercury Drop Electrode in the Alternating Current Polarographic Analysis of Thallium(I)
Authors: Kodama Mutsuo , Noda Tomohiko 
Published: July 2006

Abstract
The use of a hanging mercury drop electrode (HMDE) in the a.c. polarographic determination of thallium was studied systematically. Analysis was carried out by scanning anodically the potential of HMDE from the limiting-current potential region at a constant scanning rate and by measuring the a.c. peak-height for the anodic stripping process of thallium. Thallium could be concentrated effectively on the HMDE at the initial stage of this procedure and then stripped anodically. By employing this technique, a marked increase in sensitivity could be obtained and 1.0×10−6 m thallium(I) in an EDTA solution was determined accurately. The interference effects of lead, cadmium, zinc, and indium on the determination of thallium were also investigated. When the electrolysis was initiated in the limiting-current potential region of lead(II), the peak-height of thallium was found to be enhanced markedly.
1-Acylindoles. VI. On the Deacylation of the N′-Position’in the Formation of a 1,2,3,4-Tetrahydrocarbazole
Authors: Yamamoto Hisao , Atsumi Toshio 
Published: July 2006

Abstract
The cyclization reaction of cyclohexanone acetylphenylhydrazone to produce a tetrahydrocarbazole derivative has been reinvestigated. Although other workers obtained only a deacylated derivative in the reaction products, we found also an acylated product. It can be concluded from the experimental results that an acyl group of the N1-position of a phenylhydrazine derivative participates only a little in the indole cyclization and that the deacetylation occurs mainly after formation of a new C–C bond.
Calorimetric Study of the Glassy State. III. Novel Type Calorimeter for Study of Glassy State and Heat Capacity of Glassy Methanol
Authors: Sugisaki Masayasu , Suga Hiroshi , Seki S\^{y}uzô 
Published: July 2006

Abstract
An adiabatic Nernst-Type calorimeter with a cell for condensing a sample vapor as an amorphous state was constructed. By making use of this calorimeter, the heat capacities of the glassy, supercooled liquid, and crystalline states of methanol were measured from 20°K to 120°K. It was found that the state of methanol deposited on the chilled substrate at about 95°K from its vapor state shows a glass transition phenomenon at about 103°K accompanied with the sudden increase of heat capacity, ΔCP, amounting to 26 J/(mol°K). The drastic crystallization with the exothermic effect coming to 1.54 kJ/mol was observed near 105°K. The residual entropy for the glassy methanol was found to be 7.07 J/(mol°K). Based on these results it seems very plausible to propose that any non-crystalline solid deposited on the chilled substrate from the vapor state will show the glass transition phenomenon.
Diffuse Reflection Spectra of Some Würster Salts
Authors: Iida Yôichi , Matsunaga Yoshio 
Published: July 2006

Abstract
Nine Würster salts derived from p-phenylenediamine, benzidine, and their N-methyl derivatives were examined for diffuse reflection spectra and classified into three groups, namely, those showing a strong charge-transfer band similar to that in the solution’s dimer spectrum, those showing a strong α-band characteristic of the monomer and a relatively weak charge-transfer band, and, finally, those showing a spectrum which bears no resemblance to either the monomer or dimer spectrum. The mode of intermolecular interaction in these cation-radical salts was speculated upon on the basis of the spectra and the magnetic susceptibilities.
The Chelate Formation of o-Substituted Phenylazochromotropic Acids with Alkaline Earth Metals
Authors: Nakashima Susumu , Miyata Haruo , Toei Kyoji 
Published: July 2006

Abstract
The acid dissociation constants of phenyl, o-, m-, and p-sulfophenyl-, o-carboxyphenyl-, o-phenol- and o-arsonophenylazochromotropic acid and the formation constants of their 1:1 metal chelates with alkaline earth metals have been measured by potentiometric titration. The measurements have been carried out at 25°C and μ=0.10 (KNO3). The influence of these substituents on the acid dissociation constants of the reagents, and on the chelate formation constants was discussed. The dissociation constants of the naphtholic protons of the o-substituted reagents increase as follows: o-OH&lt;o-AsO(OH)2&lt;o-COOH&lt;o-SO3Na&lt;o-H. The metal chelate stabilities of o-phenol-, phenyl- and o-arsonophenylazochromotropic acids decrease as follows: Mg&gt;Ca&gt;Sr&gt;Ba, while for chelates of o-carboxyphenyl- and o-sulfophenylazochromotorpic acids the order is Mg&gt;Ca&gt;Sr≈Ba. The sulfonic group in o-sulfophenylazochromotropic acid, in spite of its remarkable electron-withdrawing effect, depress the acid dissociation, and form more stable barium chelate than phenyl-, m- and p-sulfophenylazochromotropic acid do. The plot of the formation constants, logK, against the sum of the dissociation constants, pKA(=pka1+pka2+pka3), was approximately linear.