bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies of Peptide Antibiotics. III. Cyclo-(l-valyl-l-ornithyl-l-leucyl-d-phenylalanylglycyl)2
Authors: Aoyagi Haruhiko , Kato Tetsuo , Ohno Motonori , Kondo Michio , Waki Michinori , Makisumi Satoru , Izumiya Nobuo 
Published: July 2006

Abstract
A cyclic decapeptide, cyclo-(l-valyl-l-ornithyl-l-leucyl-d-phenylalanylglycyl)2, has been synthesized in an attempt to obtain information about the relation of the structure to the antibacterial activity of gramicidin S.
The synthesis of the cyclic decapeptide was achieved in two ways. The condensation of p-methoxybenzyloxycarbonyl-l-valyl-δ-benzyloxycarbonyl-l-ornithyl-l-leucyl-d-phenylalanylglycine azide with l-valyl-δ-benzyloxycarbonyl-l-ornithyl l-leucyl-d-phenylalanylglycine afforded the corresponding N-blocked decapeptide, which was converted to the p-nitrpohenyl ester by the action of di-p-nitrophenyl sulfite. After the p-methoxybenzyloxycarbonyl group had been removed with trifluoroacetic acid, the decapeptide p-nitrophenyl ester was transformed to the cyclic benzyloxycarbonyl-substituted decapeptide by treatment with pyridine. On the other hand, this compound was also obtained by a dimerization reaction of l-valyl-δ-benzyloxycarbonyl-l-ornithyl-l-leucyl-d-phenylalanylglycine p-nitrophenyl ester. In the latter case, however, the yield was poor. The cyclic benzyloxycarbonyl-substituted decapeptide was hydrogenated in the presence of palladium black to give the desired cyclic decapeptide dihydrochloride.
The effects of the synthesized cyclic decapeptide on bacterial growth have also been examined. It was observed that the compound was about ten times as active as gramicidin S against B. subtilis in a synthetic medium; however, it showed silghtly less activity than gramicidin S in a bouillon agar medium.
The Metal-catalyzed Autoxidation of Tetralin. V. The Effect of Fatty Acid Solvents
Authors: Kamiya Yoshio 
Published: July 2006

Abstract
The rate of the cobalt-catalyzed decomposition of tetralin hydroperoxide in fatty acid solvents was first order with respect to hydroperoxide and second order with respect to the cobalt, and it was inversely proportional to the square of the acid concentration; i.e., -dROOH/dt=″(Co)2·(ROOH)/(Acid)2. The rate constant, k″, was found to be almost constant, regardless of the molecular weight of the acid. The values of k3⁄k61⁄2 obtained from the limiting rate of the oxidation showed an excellent linear correlation against the dielectric function of (D−1)/(2D+1). The rate of the oxidation of tetralin calculated by -dO2/dt=k3(k1′⁄2k6)1⁄2(RH)(Co)−k1′(Co)2/2 showed an excellent agreement with the value observed at cobalt concentrations lower than 3×104 mol./l. Strong organic acids such as chloroacetic acids deactivated the cobalt catalyst, and oxalic acid, which has shown the strongest deactivating effect of all the acids tested, deactivated equimolar cobalt salt.
The Cross-linking Reaction of the Poly butadiene Binder for Composite Propellants
Authors: Yamazaki Kiroku , Tokui Harusuke 
Published: July 2006

Abstract
The cross-linking reactions of carboxy-terminated polybutadiene with tris[1-(2-methyl)aziridinyl] phosphine oxide have been studied in order to obtain an excellent fuel binder of good mechanical properties as well as good combustion characteristics.
The tensile strength and elongation at the break point, as shown by the elastomer studied, were about 10–15 kg./cm.2 and 250–500% respectively. For high tensile modulus of the elastomer, an 100–200% excess of the cross-linking agent over the equivalent ratio was required.
The reaction temperature for cross-linking was lowered to the 50–70°C range by the addition of a suitable accelerator.
The stress-strain curve of the elastomer closely fit the equation for the rubber elasticity theory, and these stress-strain data was in accordance with the measured swelling data.
The Radiation-induced cis-trans Isomerization of 2-Butenes by Hydrogen Sulfide
Authors: Sugimoto Ken’ichi , Ando Wataru , Oae Shigeru 
Published: July 2006

Abstract
Radiation-induced free radical isomerizationsxs of 2-butenes with hydrogen sulfide at room temperature gave identical mixtures of about 72% trans- and 28% cis-butenes. The G-value of the isomerization is 20 to 50 times larger than that of the formation of the addition product. With gamma irradiation, 2-butenes in the presence of hydrogen sulfide were rapidly isomerized, even with a very small radiation dose. This ready isomerization indicates the ease of the reversibility of the first step of the sulfhydryl-radical addition reactions.
A Deuteron Magnetic Resonance Study of Urea-d4
Authors: Chiba Takehiko 
Published: July 2006

Abstract
A deuteron magnetic resonance study has been made on a single crystal of urea-d4. At room temperature deuteron quadrupole coupling corresponding to a stationary molecule is obtained. The eqQ and η values determined are: eqQ⁄h=210.8±1.0 kc./sec. and η=0.139±0.010 for D1, and eqQ⁄h=210.7±1.0 kc./sec. and η=0.146±0.010 for D2 at room temperature, and eqQ⁄h=206.3±1.2 kc./sec., η=0.138±0.010 for D2 at 117°C. In both cases the maximum field gradient component and the N–H direction are in good agreement.
The onset of reorientational motion about the C=O bond of a whole molecule has been concluded from the line-width change at high temperatures. Above 110°C the effect on the line-width of the reorientation about C–N bond has also been observed. The barrier heights for these motions are estimated to be 11±2 kcal./mol. for the reorientation about the C=O bond and 15±3 kcal./mol. for that about the C–N bond. The temperature dependence of the quadrupole splitting and that of the dipole coupling between 14N and D have been observed and dicussed in relation to the motion of the urea molecule.
The Structure and Stereochemistry of Four New Sesquiterpenes Isolated from the Wood Oil of “Kaya” (Torreya nucifera)
Authors: Sakai Tsutomu , Nishimura Kiichi , Hirose Yoshio 
Published: July 2006

Abstract
Four new sesquiterpenes, nuciferal (II), nuciferol (III), torreyal (IV) and neotorreyol (V), together with dendrolasin and o-methoxycinnamic aldehyde, have been isolated from the neutral volatile wood oil of Kaya (Torreya nucifera Sieb. et Zucc.) by adsorption chromatography on silica gel.
The structures and stereochemistry of these new compounds have been confirmed by infrared, ultraviolet, NMR and MS spectrometry, as well as by chemical methods.
Equilibrium Study of Propylenediaminetetraacetato Complexes of Some Divalent Metal Ions
Authors: Tanaka Nobuyuki , Ogino Hiroshi 
Published: July 2006

Abstract
The relative stability constants of propylenediaminetetraacetato complexes (KM′M=KMY⁄KM′Y) of six metal ions were determined at 25°C and ionic strength 0.2 by the polarographic method reported previously. The values obtained are KCoCu=3.7×102, KNiCu=1.66, KZnCu=3.2×102, KCdCu=1.61×102 and KPbCu=8.8 and are Quite similar to the corresponding values of the ethylene-diaminetetraacetato complexes respectively.
Vibration-Rotation Spectra, the Coriolis Coupling Constants and the Intramolecular Force Field of Symmetric Top Molecules. I. The E-type Fundamental Bands of Methyl and Methyl-d3 Halides
Authors: Morino Yonezo , Nakamura Junko 
Published: July 2006

Abstract
The infrared spectra of CH3X and CD3X (X=Cl, Br and I) have been observed with a high-resolution instrument in the region 500–3300 cm−1. The rotational fine structures of all the E-type fundamental bands have been resolved and analyzed, giving the Coriolis coupling constants, the rotational constants and the frequencies of the band origins. The uncertainties of the observed molecular constants have been discussed. On the basis of the observed data for the rotational constants and their changes by the excitation of vibration, the structures of methyl halide molecules have been determined.
Adsorption of Trimethylamine, Ammonia and Pyrrole on Amorphous Silica-alumina
Authors: Tezuka Yosisato , Takeuchi Toyosaburo 
Published: July 2006

Abstract
The adsorptions of trimethylamine, pyrrole and ammonia on pure silica, alumina and three silica-aluminas with (2%, 13% and 26% of alumina) have been studied. Isosteric heats have been obtained from adsorption isotherms at 100 and 120°C. A conspicuous rise, followed by a gradual fall, was observed at an early stage of the heat curve obtained from the isotherm on silica-alumina, but not from those on silica and alumina. At the peak of the curve, the amount of the adsorption of trimethylamine agreed with that of pyrrole, both of which, again, agreed with the amount of the acid point as measured by the titration using n-butylamine. The amount of ammonia was twice as large as that of the acid point. The acid points of silica-alumina are assumed to exist in clusters on the surface. The rise of heat is due to the mutual interaction of the adsorbed molecules, the peak indicating the completion of the monolayer on such acid domains.
On Glumamycin, a New Antibiotic. V. The Steric Configuration of α,β-Diaminobutyric Acid
Authors: Fujino Masahiko , Inoue Michitaka , Ueyanagi Jisaburo , Miyake Akira 
Published: July 2006

Abstract
Glumamycin has been treated with nitrous acid to convert the free amino group into hydroxyl, and the resulting deamino-glumamycin has been hydrolyzed with hydrochloric acid. A mixture of threonine and allothreonine has then been isolated from this hydro-lysate. The DNP derivative of the product shows an optical rotation [M]D24=−294°±14 (c 0.48, 4% sodium bicarbonate). This fact shows that the above product is a mixture of d-threonine and d-allothreonine.
Further, as the α, β-diaminobutyric acid obtained from the hydrolysate of deaminoglumamycin and that obtained from the hydrolysate of glumamycin have the same optical rotation, it may be concluded that the two moles of α, β-diaminobutyric acid in glumamycin have the same steric configuration.
On the other hand, the product obtained by the oxidation of α, β-diaminobutyric acid with hydrogen peroxide is in agreement with d-alanine. Thus, it has been found that the α- and β-carbons of α, β-diaminobutyric acid belong to the d series and that, consequently, α, β-diaminobutyric acid takes the d-erythroconflguration.
The Extractional Behavior of Cerium with Acetylacetone
Authors: \={O}ki Sh\={o}hachir\={o} 
Published: July 2006

Abstract
The extraction behavior of tracer amounts of cerium-144 with acetylacetone has been studied. The distribution ratio of acetylacetone between benzene and a 0.1 m sodium perchlorate solution is constant in the pH range 1.5–7, and the distribution coefficients have been determined to be 5.5, 5.4, and 5.3 at 10, 25, and 40°C respectively. The distribution ratio of cerium has been shown to be proportional to the fourth power of the concentration of the acetylacetonate ions and to the square of that of acetylacetone in the organic phase. From these results, it has been concluded that cerium exists as a tetravalent ion in the system and that the chemical form of cerium extracted in the organic phase is CeA4·2HA. Two molecules of acetylacetone are assumed to combine with CeA4 forming hydrogen bonds.
Sulfoxides. V. The Ionization of Sulfoxides in Sulfuric Acid
Authors: Oae Shigeru , Kitao Teijiro , Kitaoka Yoshinori 
Published: July 2006

Abstract
Contrary to the earlier claim that diphenyl sulfoxide ionizes in nearly 100% sulfuric acid to give a “diphenyl sulfidonium” ion, which can then return to the original sulfoxide when quenched with water, the 18O tracer experiment and a new set of cryoscopic determinations of a few sulfoxides have revealed that the dissociation of the sulfoxide takes place in a concentrated sulfuric acid in the following manner:
(Remark: Graphics omitted.)
Particle-size Determination of Suspensions or Emulsions by Viscometry
Authors: Matsumoto Sachio 
Published: July 2006

Abstract
An apparatus for sedimentation analysis by the viscometric method, making possible the measurement of viscosity change with time at a fixed position in the bulk due to the sedimentation or ascension of dispersed particles, has be constructed. The new method has been examined with both a potato-starch-granule suspension and oil-in-water emulsions.
Quinoxaline Derivatives. V. Some Reactions of 2-Cyano-3-hydroxyquinoxaline 1-Oxide
Authors: Ahmad Yusuf , Habib M S , Iqbal M , Ziauddin  
Published: July 2006

Abstract
2-Cyano-3-hydroxyquinoxaline 1-oxide (Ia), and its 7-chloro- or 7-ethoxy-derivatives (Ib, c), on treatment with aniline, are deoxygenated, with a simultaneous displacement of the nitrile group, resulting in the formation of 2-anilino-quinoxalines (IIa, e and f). Ia undergoes similar transformations with N-methylaniline and cyclohexylamine.
The N-oxide (Ia), on being heated with fuming hydrobromic acid, yields 6-bromo-2,3-dihydroxyquinoxaline (IVa), the mechanism of formation of which has been outlined.
Electronic Spectra of 1,4,9,10-Anthradiquinone and Its Complexes with Aromatics
Authors: Kuboyama Akira , Wada K\={o}ichi 
Published: July 2006

Abstract
The electronic spectrum of 1,4,9,10-an-thradiquinone, and the charge transfer absorption bands of molecular complexes between 1,4,9,10-anthradiquinone and aromatic compounds in solutions, have been studied. The weak absorption band near 600 mμ (εmax∼20) of 1,4,9,10-anthradiquinone has been assigned to an n→π* band. The charge transfer absorption bands of the molecular complexes are found at nearly the same positions as those of the corresponding chloranil complexes. From this fact it has been conluded that the electron affinity of 1,4,9,10-anthradiquinone is nearly the same as that of chloranil.
Monolayer Studies of the Interactions between Histidyl Polypeptides and Metal Ions. II. The Effects of Copper, Zinc, Cobalt and Calcium Ions on the Monolayer Properties of Poly-1-benzyl-l-histidine
Authors: Yamashita Takuya , Isemura Toshizo 
Published: July 2006

Abstract
The effects of metal ions on the monolayer properties of poly-1-benzyl-l-histidine, a model substance of the histidyl residue in protein, have been investigated at the air/water interface when the subphase pH is varied, and at the oil/water interface at pH 5.6.
At the air/water interface, it was found from the measurements of the surface viscosity that the cupric ion interacts especially strongly with the monolayer of poly-1-benzyl-l-histidine over a wide pH range and that the interaction of the calcium ion is quite weak. The decreasing order of metal-monolayer interactions is Cu2+, Zn2+, Co2+, Ca2+. The surface pressure-area isotherms suggest that the cobalt ion forms a somewhat looser cross-linked structure in the monolayer than does the zinc ion because of its weaker interaction.
At the oil/water interface, the film expands remarkably because of the release of van der Waals force between side chains. No appreciable effects on the interfacial pressure-area relation were observed with the zinc and cobaltous ions, because the accessibility of these ions to the interacting sites of side chains would have been restricted by the oil. The cupric ion had a considerable effect here as well as at the air/water interface.
A Microcell for Differential Thermal Analysis
Authors: Tanaka Satohiro 
Published: July 2006

Abstract
Microcells to carry out differential thermal analysis using a small amount of a sample have been described. The features of these cells are that they are small and light in weight, and are supported only by a thermocouple, not coming in contact with the wall of the metal block. The effects have been described of the variation in heating rate and in sample amount. The peak areas of the benzoic acid melting curve are proportional to the sample amount. The melting temperature can be measured with a precision of ±1°C if the heating rate is less than 2°C/min. The improvement of the quality of the microcell has also been considered.
The Mechanism of the Electrical Conduction in Solid Acetamide
Authors: Hirano Koichi 
Published: July 2006

Abstract
1) Conductivity measurements of solid acetamide have been carried out over the temperature range of 60–90°C and the specific conductivity, κ=1.7exp−{34×103⁄RT} Ω−1. cm−1, has been determined.
2) The mechanism of conduction has been discussed in terms of the proton transfer, and the value of the potential barrier between two positions of equilibrium in the NH…O hydrogen bonds has been estimated.
Synthetic Studies starting from β-Cyanopropionaldehyde. II. The Syntheses of Aliphatic Aldehydes and ω-Aldehydic Acids
Authors: Motoki Shinichi , Satsumabayashi Sadayoshi , Kusano Hajime 
Published: July 2006

Abstract
Electrolysis of the ethylene acetal of β-formylpropionic acid with butyric acid gave caproaldehyde ethylene acetal as a result of crossed coupling. Crossed electrolysis with monoesters of succinic, adipic and sebacic acid were then studied. The expected products, adipinaldehydic, suberinal dehydic and ω-formylundecylic acid, were obtained as their ethylene acetal ester respectively. As ω-aldehydic acids are usually inaccessible compounds, these electrolytic reactions may provide a new convenient synthetic route.
Furthermore, it has been found that the tetramer of β-formylpropionic acid underwent the normal electrolytic reaction in the presence of fatty acids and the corresponding aliphatic aldehydes were obtained in relatively good yields.
Reaction of Bis(acetylacetonato)copper(II) with Bromine
Authors: Nakamura Yukio , Kawaguchi Shinichi 
Published: July 2006

Abstract
In the reaction of bis(acetylacetonato)-copper(II) with bromine the chelate ring is broken and 3-bromoacetylacetone and copper-(I) or copper(II) bromide are formed depending on the mole ratio of the reactants.
Bis(3-bromoacetylacetonato)copper(II) also reacts with bromine in a similar fashion resulting in 3, 3-dibromoacetylacetone and copper(I) or copper(II) bromide. The possibility of the copper(II) ion functioning as a catalyst in the second step of the bromination of acetylace-tone is suggested.
The Molecular Structure and Force Constants of Boron Trifluoride and Boron Trichloride
Authors: Konaka Shigehiro , Murata Yoshitada , Kuchitsu Kozo , Morino Yonezo 
Published: July 2006

Abstract
The interatomic distances and the mean amplitudes of BF3 and BCl3 have been determined, by the sector-microphotometer method of gas electron diffraction, to be: rg(B—F)=1.3156±0.0044 Å, rg(F···F)=2.2733±0.0041 Å, l(B—F)=0.0398±0.0029 Å, and l(F···F)=0.0541±0.0020 Å for BF3 and rg(B—Cl)=1.7421±0.0044 Å, rg(Cl···Cl)=3.0134±0.0060 Å, l(B—Cl)=0.0505±0.0023 Å, and l(Cl···Cl)=0.0700±0.0023 Å for BCl3. The force constants have also been determined from the mean amplitudes. Their values are in good agreement with those obtained by the isotopic shifts and by the Urey-Bradley force field. The complex scattering factors for B, F, and Cl have been calculated from the Hartree-Fock potential, and it has been shown that the background intensity and the mean amplitudes of BF3 and BCl3 are much better accounted for by these scattering factors than by those calculated from the Thomas-Fermi potential.
The Homogeneous Hydrogenation of Acetylenes by Dicyclopentadienyltitaniumdicarbonyl
Authors: Sonogashira Kenkichi , Hagihara Nobue 
Published: July 2006

Abstract
The homogeneous hydrogenation of acetylenes and olefins in the presence of dicyclopentadienyltitaniumdicarbonyl (I) was studied. The results of the hydrogenation varied with the acetylene substituent. The relative activating effects of the substituents on the hydrogenation of such acetylenes as RC≡CH and R′C≡CR′ are as follows: R: Ph&gt;t-butyl&gt;n-alkyl, R′ : Ph&gt;n-alkyl. The order is the reverse of that observed with the usual metal catalysts of the VIII group. In order to elucidate the mechanism of hydrogenation, the reaction of the dicarbonyl (I) with various acetylenes was studied, and the structures of the products were discussed.
Syntheses of Organic Phosphates. I. Pyridylmethyl Phosphates
Authors: Murakami Yukito , Takagi Makoto , Nishi Hiroshi 
Published: July 2006

Abstract
The reaction of pyrophosphoric acid with 2-, 3- and 4-pyridylmethanols resulted in the formation of the corresponding pyridylmethyl phosphates. The separation of each ester from the corresponding phosphorylation mixture was performed by passing the mixture through a column of Dowex 50W-X8 [H+] resin. The 2-, 3-, and 4-isomers were recrystallized from ethanol-water as white crystals with melting points of 182—182.5°C (part, decomp.), 194.5—195.5°C (part, decopm.), and 201.5—202.5°C (decomp.) respectively. An attempt to separate each of these esters from an artificial mixture of them consisting of an equal amount of each was performed by using an ion-exchange resin, Dowex 50W-X8 [H+]. The acid dissociation constants were determined by a potentiometric method at 25.0°C and μ=0.10 m (KNO3); this gave three pK’s for each phosphate, PKH3A, PKH2A, and PKHA: 2-pyridylmethyl phosphate, 1.8, 4.42, 6.29; 3-pyridylmethyl phosphate, 1.9, 4.86, 6.23; 4-pyridylmethyl phosphate, 1.7, 5.14, 6.25. Of these pK’s, PKHA refers to the dissociation of a pyridinium proton, while the other pK’s refer to those of phosphate protons.
The Intermolecular Hydrogen Bonding between Methanol and Triethylamine in Various States
Authors: Hirano Etsuko , Kozima Kunio 
Published: July 2006

Abstract
The intermolecular hydrogen bond energy between methanol and triethylamine was determined by infrared studies in the vapor state and in solutions. It was also found that, with an increase in the dielectric constant, ε, of the solvents, the free O–H stretching band of methanol shifts to a lower frequency, the molar absorptivity of this band increases, and the hydrogen bond energy of this system decreases. As is well known, the hydrogen-bonded system is mainly stabilized by the contribution of two resonating structures, the non-bonded structure and the charge-transfer structure. It seems probable that the weight of the latter for a relatively weak hydrogen-bonded complex is small. Therefore, if the energies for both resonating structures are assumed to be mainly determined by the electrostatic interaction, the hydrogen bond energy may be expected to be reciprocal to the dielectric constant of the environment. This is actually true within the limits of experimental error in a few solutions. It was also found, however, that the relation cannot be extrapolated to the case of ε=1, i. e., to the case of vapor.
The Direct Iodination of Polyalkylbenzenes Bearing Bulky Groups
Authors: Suzuki Hitomi , Nakamura Kiyomi , Goto Ryozo 
Published: July 2006

Abstract
The following polyalkylbenzenes bearing bulky groups have been subjected to direct iodination using iodine and periodic acid, and the corresponding mono-iodinated products have been obtained in fairly high yields: 4-t-butyl-1, 2-dimethylbenzene, 5-t-butyl-1, 3-dimethylbenzene, 5-t-butyl-1, 2, 3-trimethylbenzene, 1, 2, 4, 5-tetraisopropylbenzene and p-di-t-butylbenzene. The polyiodination of polymethylbenzenes has also proceeded smoothly, giving polyiodo compounds in high yields. A comparison of various direct methods has proved the above reagent to be the best iodinating agent for a variety of polyalkylbenzenes.
The Electron Spin Resonance of γ-Irradiated Sodium Polyphosphate. I. The Glass and the Single Crystal
Authors: Miura Masaji , Hasegawa Akinori , Fukui Tokinori 
Published: July 2006

Abstract
Under irradiation with γ-rays at room temperature, the glass of sodium polyphosphate or its single crystal doped with sodium sulfate becomes red, whereas the pure single crystal remains colorless. The glass and the doped single crystal exhibit ESR spectra which can be attributed to the hole trapped in the non-bonding orbital on the oxygen atom. The pure single crystal, of course, exhibits no ESR spectra. The determination of the degree of polymerization in the aqueous solution of the glass showed a decrease in the length of the main chain caused by the γ-ray irradiation. It may be concluded from these facts that the P–O–P bond is ruptured under the irradiation and that the effect of γ-rays on sodium polyphosphate is closely correlated with the local strain of the P–O–P bond.