bluuebunny/crossref_metadata_2025_split huggingface dataset:
Luminescence in DNA-Acridine Dye Complexes. I. Phosphorescence and Delayed Fluorescence Due to the Triplet-Triplet Annihilation of Acridine Dyes in the Complexes
Authors: Kubota Yukio 
Published: July 2006

Abstract
When DNA-acridine dye complexes were excited by a visible light which was not absorbed by DNA, phosphorescence and a delayed fluorescence of the dye were observed. It was found, by comparing the excitation spectra with the absorption spectra, that the monomeric dyes mainly contribute to the fluorescence and phosphorescence emissions. The delayed fluorescence was interpreted as a result of the triplet-triplet annihilation which arises from two triplet dye molecules placed very close together. The decrease in the delayed fluorescence on the denaturation of DNA indicates that the interaction between the two triplets is sensitive to the conformation of the macromolecule.
The Photoreaction of 2,6-Diphenyl-4H-thiopyran-4-one and Its Related Compounds
Authors: Sugiyama Noboru , Sato Yoshiaki , Kashima Choji 
Published: July 2006

Abstract
The irradiation of 2,6-diphenyl-4H-thiopyran-4-one (1) or 2,6-diphenyl-4H-pyran-4-one (2) in an alcohol in the presence of oxygen gave benzoic acid and a benzoylacetic acid ester, while that of 2 in benzene or 2,6-dimethyl-4H-thiopyran-4-one (5) in various solvents gave the corresponding cage dimer, (9) or (10). No photoreaction could be observed in case of the irradiation of 1,2,6-trimethyl-4-pyridone (3) and 6-methyl-1,2-diphenyl-4-pyridone (4). A reaction mechanism via the triplet state of the substrate was also proposed.
Studies of the Thiocarbonyl Compounds. II. Syntheses and Thermal Rearrangement of Aryl Thionobenzoates
Authors: Araki Yoshiaki , Kaji Aritsune 
Published: July 2006

Abstract
Various aryl thionobenzoates were prepared. When maintained at elevated temperatures, they rearranged smoothly to aryl thiolbenzoates. The mechanism of this rearrangement was kinetically investigated. The rearrangement rates were correlated with the first-order kinetic equation, and the rearrangement was found to be facilitated by substitution with an electron-withdrawing group in the migrating aromatic rings. The Hammett ρ value was found to be 2.11 in diphenyl ether at 200.5°C. The entropies of activation were negative. A linear free-energy relationship existed between this rearrangement and the rearrangement of O,S-diaryl dithiocarbonates. From these observations, a four-membered cyclic structure can be suggested as the transition state for this rearrangement. The present results indicate that the existence of hetero atoms directly bound to the thiocarbonyl group is not essential for the thermal rearrangement with intramolecular 1,3 aryl migration from oxygen to sulfur.
Sugars Containing a Carbon-phosphorus Bond. II. Syntheses of Phosphinyl Sugars by the Michaelis-Arbuzov Reaction of Halogenated Sugars
Authors: Inokawa Saburo , Tsuchiya Yoshimi , Yoshida Hiroshi , Ogata Tsuyoshi 
Published: July 2006

Abstract
3,5-O-Benzylidene-6-deoxy-6-diethoxyphosphinyl-1,2-O-isopropylidene-α-d-glucofuranose was prepared in an 80% yield by heating a solution of 3,5-O-benzylidene-6-deoxy-6-iodo-1,2-O-isopropylidene-α-d-glucofuranose (1) in an excess of triethyl phosphite (5). Similarly, 6-deoxy-6-diethoxyphosphinyl-1,2;3,4-di-O-isopropylidene-α-d-galactopyranose was prepared in a 95% yield from 6-deoxy-1,2;3,4-di-O-isopropylidene-α-d-galactopyranose (2), and (5); 5-deoxy-5-ethoxyphenylphosphinyl-1,2-O-isopropylidene-3-O-methyl-α-d-xylofuranose was prepared in a 90% yield from 5-bromo-5-deoxy-l,2-O-isopropylidenne-3-O-methyl-α-d-xylofuranose and diethyl phenylphosphonite; 3,5-O-benzylidene-6-deoxy- 1,2-O-isopropylidene-6- (N,N′-tetraethyldiaminophosphinyl)-α-d-glucofuranose was prepared in a 44% yield from 1 and ethyl N,N′-tetraethylphosphorodiamidite (7); 6-deoxy-1,2; 3,4-di-O-isopropylidene-6-(N,N′-tetraethyldiaminophosphinyl)-α-d-galactose was prepared in a 70% yield from 2 and 7.
Synthesis of 5-Styryltropolones
Authors: Higashi Hidehiro , Kurosawa Kazu , Matsumura Hisashi 
Published: July 2006

Abstract
5-Styryl-, 5-(p-bromostyryl)-, 5-(p-chlorostyryl)-, 5-(p-methoxystyryl)-, 5-(p-methylstyryl)-, 5-(m-chlorostyryl)- and 5-(m-methylstyryl)tropolone were synthesized by the Wittig reaction of 5-formyltropolone. Their UV and NMR spectra were determined.
Studies on Hydroxy Amino Acids, III. The Synthesis of Cyclic Peptide Containing L-Serine
Authors: Iwai Michio , Nakajima Kiichiro , Uno Akio , Hase Satoe , Takeuchi Ikuko , Okawa Kenji 
Published: July 2006

Abstract
Modified gramicidin S pep tides, cyclo(Ser-Orn-Ser-d-Phe-Pro)2 and cyclo(Ser-Orn-Ser-d-Phe-Pro), were synthesized in order to clarify the correlation between the component amino acids and the antibiotic activity. To obtain the cyclic peptides, we examined several sets of conditions for cyclization reactions. The antibiotic activity of these peptides could not be found against some microorganisms in vitro. It was concluded that the lipophilic amino acids residues are the essential groups contributing to gramicidin S activity.
The Synthesis of a Partial Sequence of Proinsulin Using the A-Chain of Natural Insulin
Authors: Shimonishi Yasutsugu 
Published: July 2006

Abstract
Elongation reactions of the S-sulfonate of the A-chain of bovine insulin were carried out with acylamino acid-active esters or with acylpeptide azide; the following derivatives of the A-chain were thus synthesized: S-sulfonates of NG-nitro-l-arginyl-, l-lysyl-NG-nitro-l-arginyl-, and l-prolyl-l-prolyl-l-glutaminyl-Nε-benzyloxycarbonyl-l-lysyl-NG-nitro-l-arginyl-A-chain. Thus, this was demonstrated to be a useful procedure for the partial synthesis of proinsulin.
ζ-Potentials of Synthetic Fibers in Aqueous Solutions of Sodium Alkyl Sulfates and Viscosities of Their Solutions
Authors: Iwadare Yoshio 
Published: July 2006

Abstract
In order to study the surface-adsorption behavior of anionic surfactants on fibers, the ζ-potentials of some synthetic fibers in aqueous solutions of sodium alkyl sulfates and their mixtures mainly above the critical micelle concentration (CMC), were measured. Further, the viscosities of aqueous solutions of pure surfactants were determined. Consequently, it can be presumed, on the basis of the viscosity data, that the structure of the micelles of these agents varies at the break of the ηspm⁄cm vs. cm curve. The ζ-potentials (negative) of fibers in aqueous solutions of the agents rapidly changed with an increase in the agent concentrations, but it remained nearly constant above the CMC. At much higher concentrations, the ζ values gradually changed; thereafter, passing a break or a minimum, they became approximately constant again. The concentration at the break or the minimum observed nearly corresponded to that at the break of the ηspm⁄cm vs. cm curve. It may, therefore, be suggested that the change in ζ-potentials at high concentrations is connected with that in the structure of the micelles. The ζ-potentials (negative) of fibers in aqueous mixed solutions changed sharply with an increase in the concentration of the mixtures and thereafter, passing a maximum in the vicinity of the CMC, complicatedly changed as the total concentrations and mixing ratios changed.
Mechanism of Hydrogen Formation in the Vapor Phase Radiolysis of Methanol
Authors: Yamamoto Tatsuo 
Published: July 2006

Abstract
The yields of isotopic hydrogen in the vapor phase radiolysis of deuterated methanol (CH3OD) were found to be G(H2)=6.1, G(HD)=5.3 and G(D2)=0.2. The molecular yields of isotopic hydrogen were also determined by adding propylene as a radical scavenger, GM(H2)=1.5, GM(HD)=0.6 and GM(D2)∼0. In order to estimate the contribution of ionic species for the formation of hydrogen, the ion-molecule reaction of CH3OD has also been investigated by using a mass spectrometer of the differential pumping type. The product ions, such as (CH3OCH3CH3OD)D+ or (CH3OD)3D+, which were considered to be formed by the higher order ion-molecule reactions were observed. The mechanism of hydrogen formation was discussed on the basis of the ionic, the molecular and the radical mechanisms.
Catalytic Activity and Reactivity of Aromatic Nitrile and Alkali Metal Ion Radical Salt. II. Hydrogen Exchange on Benzonitrile Ion Salt as a Function of Alkali Metals
Authors: Tsuda Motoyuki 
Published: July 2006

Abstract
The para-orthohydrogen conversion (rate constant keH and the deuterium exchange reaction (rate constant keD) over the benzonitrile-alkali metal ion radical salt were investigated as functions of the donor component–alkali metal. The sort of alkali metals in the ion radical salts greatly affected the catalytic activity and the reactivity. The activation energies obtained from the temperature dependence of keH and keD, EH and ED, and the value of α(depending on the ratio of keH to keD monotonously decreased as Na→K→Rb, but those values showed an irregular trend for the Cs-complex. The results suggest that the catalytic activity cannot be understood only in terms of the nature of the components; must also be considered the structural nature of the solid phase of the ion radical salt.
The Thermal Decomposition of CuBr2·2NH3 and CuBr2
Authors: Tanaka Nobuyuki , Kagawa Masahiro 
Published: July 2006

Abstract
The thermal decomposition of CuBr2·2NH3 has been examined at the constant temperature, about 220°C. Copper(II) was reduced to copper(I), when bromine gas was found as one of the decomposition products, indicating that bromide anion may be the reducing agent for copper(II). The decomposition reaction of CuBr2 has been investigated by measuring the weight loss under the condition of the constant temperature. In a closed system, the reaction,
CuBr_2(s)\leftrightarrowsγ-CuBr(s)+\frac12Br_2(g)
attained to equilibrium, and ΔG° for this reaction was determined in the range from 160°C to 220°C to be given by the equation,
ΔG°(cal.)=1.10×10^4-19.3 T (160°C–220°C).
While the pressure of bromine gas was kept zero, CuBr2 decomposed following a first-order rate law in the beginning of the decomposition, and the activation energy was found to be 25.4 kcal/mol.
The Acetylation of 2,3-Dimethyl-bz-halobenzofurans and Some Reactions of the Products
Authors: Kawase Yoshiyuki , Hori Sachiko 
Published: July 2006

Abstract
The acetylation of bz-chloro- and bz-bromo-2,3-dimethylbenzofurans with acetyl chloride and aluminum chloride in carbon disulfide at room temperature was studied; it was found that the acetylation occurred at the 6- or 4-position, which is activated by the furan ring, regardless of whether the halogen atom is at the o-, the m-, or the p-position. In the cases of 7-halo compounds, diacetylation occurred to give the 4,6-diacetyl compounds, and the migration of the bromine atom of 6-acetyl-5-bromo-2,3-dimethylbenzofuran and of the methyl ester of the corresponding carboxylic acid occurred, as a result of the action of aluminum bromide in carbon disulfide at room temperature, to give the 4-bromo compounds. The haloketones thus obtained were then converted to the corresponding carboxylic acids by the bromoform reaction.
Electrochemical Properties of α-Ferric Oxide in Sulfuric Acid Solutions
Authors: Yoneyama Hiroshi , Tamura Hideo 
Published: July 2006

Abstract
I-V curves of the α-Fe2O3 electrode containing different amounts of Ti were obtained potentio statically in H2SO4 solutions. The anodic current, indicating the dissolution reaction, was almost constant and was not affected by the aH+ of the electrolyte in the potential range 0.4–1.0V vs. SCE, but it was dependent on the conductivity of the electrode. It was suggested that the dissolution reaction of this electrode is governed by the electron-transfer mechanism, much as is that of the heavily-doped N-type Ge. The flat-band potential of the α-Fe2O3 electrode was estimated on the basis of the capacity measurement. This potential changed with the aH+ of the electrolyte.
Tri(hetero)substituted Carbonium Ions. IV. Reactions of N,N′-Dimethyl-S,S′-dimethyldithiocarbamidium Ion with Various Nucleophiles
Authors: Nakai Takeshi , Okawara Makoto 
Published: July 2006

Abstract
A wide spectrum of electrophilic reactivity has been shown by N,N-dimethyl-S,S′-dimethyldithiocarbamidium perchlorate (II). Results obtained reveal that II behaves toward nucleophiles as an ambident electrophile with two reactive sites, a centered electron-definicent carbon and S-methyl carbon atom. The electrophilic behavior of II has been compared with that of a cyclic analog, 2-dimethylamino-1,3-dithiolanylium ion, and of a sulfur analog, tris (methylthio)-carbonium ion. Attempts to utilize II for synthetic reactions were made. Reactions of II with active methylene compounds gave ketone N,S-acetals which are of great interest from the standpoint of structural chemistry. o-Phenylenediamine and o-aminophenol reacted with II to give 2-dimethylamino-benzimidazole and -benzoxazole, respectively, in good yields. The reactions may provide a new method of introducing 2-dialkylamino groups into these heterocycles. Reactions of II with two equivalents of primary amines afforded tetrasubstituted guanidines. Reactions of II with p-toluenesulfonylhydrazine and an enamine were also studied.
The Synthesis of 1-Methyl-2-pyridones from 2-Chloromethylpyridines
Authors: Matsumura Eizo , Nashima Takeo , Ishibashi Fumihide 
Published: July 2006

Abstract
The reaction of 2-chloromethylpyridine (Ia) and its homologs, 5-ethyl- (Ib), 6-methyl- (Ic), and 4-methyl-2-chloromethylpyridine (Id), with pyridine gave the corresponding 1-(2′-pyridylmethyl)-pyridinium chlorides (II), from which, on heating with dimethyl sulfate, 1-methyl-2-(pyridiniomethyl)-pyridinium salts (III) were obtained. The pyridinium salts were treated with aqueous alkali at a low temperature to yield 1-methyl- (IVa), 5-ethyl-1-methyl- (IVb), 1,6-dimethyl- (IVc), and 1,4-dimethyl-2-pyridone (IVd). The reaction sequence, in combination with the 1-oxidation of 2-picolines and followed by the reaction of the 1-oxides with tosyl chloride to yield 2-chloromethylpyridines, is recommended as a convenient route for the synthesis of 1-methyl-2-pyridones starting with 2-picolines.
The Syntheses of 2-Phenethyl-2,3-dihydro-4(1H)-pyridones
Authors: Sugiyama Noboru , Yamamoto Makoto , Kashima Choji 
Published: July 2006

Abstract
In the presence of three moles of potassium amide in liquid ammonia, the reactions of β-diketones with cinnamylidenaniline gave derivatives of 1-phenyl-2-styryl-2,3-dihydro-4-pyridone. By the catalytic hydrogenation of 6-methyl-1-phenyl-2-styryl-2,3-dihydro-4-pyridone, 6-methyl-2-phenethyl-1-phenyl-2,3-dihydro-4-pyridone was obtained. When β-diketones were treated with cinnamaldehyde azine, instead of cinnamylidenaniline, 1-cinnamylidenamino-2-styryl-2,3-dihydro-4-pyridones were produced; these were then catalytically hydrogenated to the corresponding 2-phenethyl-2,3-dihydro-4(1H)-pyridones, accompanied with 2-phenethyl-1-(3-phenylpropylamino)-2,3-dihydro-4-pyridones.
Linear Conjugated Systems Bearing Aromatic Terminal Groups. III. The Synthesis and the Electronic Spectra of 1,1′-Dinaphthyl- and 2,2′-Dinaphthylpoly-ynes
Authors: Nakasuji Kazuhiro , Akiyama Shuzo , Akashi Kazuko , Nakagawa Masazumi 
Published: July 2006

Abstract
1,1′-Dinaphthylpoly-ynes (In, n=1–6) and 2,2′-dinaphthylpoly-ynes (IIn, n=1–6) were synthesized, and their electronic spectra were measured. The In-series gave an excellent agreement with the λmax∝n1.5 relationship, and the IIn-series followed a straight line, λmax∝n1.3. These relationships are different from those of 1,1′-dianthryl- and 9,9′-dianthrylpory-ynes, in which the plots of λmax versus n2 give excellent straight lines (Bull. Chem. Soc. Jap., 39, 2320 (1966); 40, 340 (1967)). The new linear relationships found in the dinaphthyl-series offer further evidence of the prominent effect of the terminal groups upon the electronic spectral properties of the conjugated poly-yne system.
The Constituents of Hops. V. The Volatile Composition of Humulus japonicus Sieb. et Zucc.
Authors: Naya Yoko , Kotake Munio 
Published: July 2006

Abstract
The steam-volatile constituents of Humulus japonicus Sieb. et Zucc. have been studied, and 50 compounds of the oil have been identified mainly by means of the temperature-programmed capillary GLC mass-spectra method. Beside the previously-reported principal components of hops (α-humulene, caryophyllene, α-copaene, α- and β-selinenes, γ-cadinene, caryophyllene-oxide, and humulene-epoxide-II), benzyl alcohol and phenethyl alcohol were found in high concentrations, whereas the myrcene was negligible. The proportion of the main compound, humulene, to the next highest one, caryophyllene, was approximately in the ratio of two to one, as in the essential oil of H. lupulus. As far as the chemical composition of the essential oils is concerned, H. japonicus seems to be related rather more closely to H. lupulus than to H. cordifolius.
Redox Reactions on α-Ferric Oxide Electrode
Authors: Yoneyama Hiroshi , Hamamatsu Shi\v{n}iichi , Tamura Hideo 
Published: July 2006

Abstract
The redox reactions of Fe(CN)64−/Fe(CN)63−, Fe2+/Fe3+, and Ce3+/Ce4+ systems on α-Fe2O3 electrodes containing different amounts of titanium were studied. The anodic current showed a tendency to be saturated in the Fe(CN)64−/Fe(CN)63− and Fe2+/Fe3+ systems. The forward direction of the current flow in these systems was the reverse of the case with the lithiated NiO electrode. On the other hand, the cathodic current flow was negligible and the redox potential was not observed for the Ce3+/Ce4+ system. It was concluded that the reaction proceeds through electron transfer and that I–V curves are determined by the influence of the potential barrier formed on the electrode surface over which an electron transfers from the electrode into the electrolyte or in the reverse direction.
The γ-Radiolysis of Liquid n-Hexane. The Effects of Radical, Electron, and Positive-ion Scavengers
Authors: Shinsaka Kyoji , Shida Shoji 
Published: July 2006

Abstract
The effects of various additives, SF6, NH3, C2H5OH, N2O, NO, SO2, and C2H4, on the product yields in the γ-radiolysis of liquid n-hexane at room temperature have been investigated. The following conclusions have been drawn: (i) The added SO2 acts mainly as a radical scavenger. (ii) The added NO shows not only the effect of radical scavenging, but also other effects. Therefore, it is inadequate to use NO as a simple radical scavenger, (iii) The C7-C12 products are formed from a combination reaction of alkyl radicals, but not from an ion-molecule reaction, (iv) The formation of C6H13+ ions by the direct action of radiation is suggested, (v) The G-value of ionization is evaluated to be 4.0. A brief discussion concerning the formation of N2 in the presence of N2O is also given.
Far Infrared Transmission Spectra and Lattice Vibrations of RbNiF3 and CsNiF3
Authors: Kohn Kay , Nakagawa Ichiro 
Published: July 2006

Abstract
The infrared absorption spectra of RbNiF3 and CsNiF3, both with a perovskite-like structure, have been measured in the region 500–50 cm−1 at room temperature and at liquid nitrogen temperature. The observed bands can be classified into three groups, corresponding to the three absorption bands in perovskite. These bands can reasonably be assigned on the basis of the crystal symmetry of the investigated compounds. A normal coordinate analysis of a crystal as a whole has been performed, where the interatomic force constants between the atom pairs within a distance of 3.5 Å are taken into account. It was shown that the normal coordinate treatment of the opticallyactive vibrations on the basis of a molecular dynamics model is useful for the interpretation of the lattice vibrations in these fluorides. The effects of the structural differences of the lattice vibrations are discussed.
The Behaviour of the Copolymer of l-Proline and O-Benzyl-l-Tyrosine in a n-Propanol and Water System
Authors: Iio Takayoshi , Takahashi Sho , Kobayashi Shoyu 
Published: July 2006

Abstract
A copolymer consisting 95.8% of l-proline and 4.2% of O-benzyl-l-tyrosine was transformed in conformation from Form I to Form II as the propanol content changed from 100% to 74%. In Form I, the copolymer took a rod-like structure like that of poly-l-proline Form I, and the O-benzyl-l-tyrosyl residue moved independently of the molecular motion of the copolymer. On the other hand, the copolymer became flexible in Form II and the components associated with each other, forming an amorphous aggregation, when the propanol content decreased further, below the transition point. The hydrophobic interaction between the O-benzyl-l-tyrosyl side chain and the prolyl residue was the main factor which made the components of the copolymer associate with each other and form an amorphous aggregation. This was verified by a fluorescence study of the O-benzyl-l-tyrosyl residue.
Kinetics of Multidentate Ligand Substitution Reactions. VIII. Substitution Reactions of Diethylenetriaminepentaacetic Acid with Nickel(II) Iminodiacetate and Aspartate Chelates and of Cyclohexane-1,2-diamine-N,N,N′,N′-tetraacetic Acid with the Nickel(II) Aspartate Chelate
Authors: Kodama Mutsuo , Ueda Teiko 
Published: July 2006

Abstract
The substitution reactions of diethylenetriaminepentaacetic acid (DTPA) with nickel(II) chelates of iminodiacetic acid (IDA) and aspartic acid (Asp) and of cyclohexane-1,2-diamine-N,N,N′,N′-tetraacetic acid (CyDTA) with the nickel(II) chelate of aspartic acid were studied by employing the polarographic method. All the reactions studied were found to proceed through the following two simultaneous reaction paths:
(Remark: Graphics omitted.)
where NiX0 and NiX22− denote nickel(II)-IDA or Asp chelates of 1-to-l and 1-to-2 compositions respectively, and where Zm− indicates a completely-deprotonated DTPA or CyDTA anion. From a comparison of the rate constants of substitution reactions involving the nickel(II)-aspartate chelate with the corresponding rate constants of substitution reactions involving the nickel(II)-iminodiacetate chelate, the six-membered ring of the nickel(II)-aspartate chelate, as compared with its five-membered ring, was concluded to be more labile in the substitution reaction.
Studies of Hydrogenolysis. LVII Catalytic Hydrogenation of Benzalacetophenone Oxide
Authors: Sohma Akiko , Mitsui Sekio 
Published: July 2006

Abstract
The effects of catalysts and an additive, sodium hydroxide, on the catalytic hydrogenation of benzalacetophenone oxide (I) have been studied for the purpose of elucidating the selectivity of the catalysts on the hydrogenation. The catalytic hydrogenation over palladium or Raney nickel led to the formation of the hydroxyketones as the primary products resulting from the hydrogenolysis of the epoxide ring. 1,3-Diphenylpropane-1,2-diol (III) was obtained by the catalytic hydrogenation over palladium, while 1,3-diphenylpropane-1,3-diol (VI) and III were yielded over Raney nickel. Under the basic conditions III was predominantly produced even over Raney nickel. Over platinum oxide, 2,3-epoxy-1,3-diphenylpropan-1-ol (VIII) was the primary product of the hydrogenation of the carbonyl group of I. In the hydrogenolysis of VIII, 1,2-diol (III) was produced regardless of the species of the catalysts.
A Comparative Study of the Constituents of Volatile Oils of Zanthoxylum
Authors: Sakai Tsutomu , Yoshihara Kazuo , Hirose Yoshio 
Published: July 2006

Abstract
The constituents of the volatile oils of three Zanthoxylum species were studied on the basis of the preceding exhaustive analysis of fruit oil from the Japanese pepper. It seems that the fragrance quality among the genera Zanthoxylum depends on the content of citronellal in the essential oil. That is, the unripe fruit oil of Japanese pepper with the strongest characteristic aroma contained the largest amount of citronellal. Ripe fruit oil of Z. simulans containing a trace amount of citronellal had a poor flavor.