bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ion-exchange Chromatographic Analysis on the Chain Length of Polyphosphate Products
Authors: Matsuura Niro , Lin Tsin-ko , Kobayashi Yoshimitsu 
Published: July 2006

Abstract
The ion-exchange chromatographic technique was used in order to find the average chain number of a polyphosphate product. For the assignment of the nth polymer in the obtained chromatogram, the dependence of the distribution coefficient, Kd, on the eluent concentration examined by the use of both 20-cm and 60-cm resin columns. A lower series of polyphosphate was included in a relatively large amount in order that the average chain number based on the chromatographic analysis could be duly appreciated only for the case of basic polymers with lower molecular weights. For a product “Graham Salt” with a number of phosphate links, the higher series of polyphosphate could not be desorbed entirely from the resin column; the accurate estimation of the average number was, then, improbable. The viscosity method is also not advisable to use the computation of a mean polymerization number in the polyphosphate with a low molecular weight. An attempt was made to improve the data on the average chain number by the viscosity measurements together with the chromatographic analysis of the polymer constituent.
Compounds Related to Acridine. VII. The Synthesis of 9-Ethynylacridine and Its Reaction with p-Nitrosodialkylaniline
Authors: Tsuge Otohiko , Torii Akiyoshi 
Published: July 2006

Abstract
The dehydrobromination of 9-(1,2-dibromoethyl)acridine, which had easily been obtained by the bromination of 9-vinylacridine, to 9-ethynylacridine was attempted by several methods, and it has been established that this transformation can be effected in a 55% yield by the use of methanolic potassium hydroxide in dioxane. It has been found that the reaction of 9-ethynylacridine with p-nitrosodialkylaniline under the influence of hydrochloric acid in ethanol leads to the formation of the corresponding 1-(9-acridinyl)-1,2-bis(p-dialkylaminophenylimino)ethane N1,N2-dioxide. In addition, the configuration of the dioxide has also been proposed on the basis of spectroscopic studies and an inspection of the Dreiding models.
The Constituents of Hops. IV. The Volatile Composition of Humulus Lupulus L. var. cordifolius Maxim.
Authors: Naya Yoko , Kotake Munio 
Published: July 2006

Abstract
The steam-volatile constituents of Humulus Lupulus L. var. cordifolius Maxim, have been studied, and 66 compounds of the oil have been identified. Besides the previously-reported principal hop components (myrcene, β-humulene, caryophyllene, β-selinene, δ- and γ-cadinenes), evidence was found for the presence in an abnormally high concentration of others: zingiberene, α-curcumene together with β-bisabolene, and β-sesquiphellandrene, selina-3,7(11)-diene, and selina-4(14),7(11)-diene. A number of oxygenated sesquiterpenoids were detected. The major one was found to be caryophyllene-oxide. The isolated components were identified by spectroscopic or chemical means.
Nucleation in Liquid Sulfur Droplets
Authors: Hamada Shuichi , Nakazawa Yoshihiro , Shirai Toshiaki 
Published: July 2006

Abstract
The freezing behavior of supercooled liquid sulfur droplets were studied by means of a microscopic method. The number fraction of the solidified droplets in the experiments of continuous cooling on well-purified sulfur was only about 15% over the temperature range from 120°C to −70°C at the cooling rate of 0.20°C/min, and no abruptly discontinuous nucleation was found in these supercooling temperatures. The number fractions of the solidified droplets were found to be related to their volumes below −20°C. The nucleations in the well-purified liquid surfur droplets were confirmed to be a homogeneous process under these conditions. The specific nucleation rates per unit of volume were estimated to be 0.450, 1.13, and 1.16 cm−3sec−1 at the specified temperatures of −20, −40, and −50°C respectively. The dependences of (lnI+ΔFA⁄kT) on 1⁄(ΔT)2T obeyed the theory of Turnbull and Fisher. The interfacial free energy of sulfur at the liquid-crystal surface was estimated to be 12.1 erg/cm2; this value was considered to be an appropriate one according to the Zadumkin consideration.
Luminescence in DNA-Acridine Dye Complexes. II. Sensitized Delayed Fluorescence in the Complexes
Authors: Kubota Yukio 
Published: July 2006

Abstract
When frozen aqueous solutions of DNA-acridine dye complexes or nucleotide-dye mixtures were excited by ultraviolet light, a sensitized delayed fluorescence of the dye was observed. This delayed fluorescence was interpreted by means of a mechanism in which the excitation energy is transferred from the triplet state of the nucleotides to the first excited singlet state of the dye. The efficiency and decays of the sensitized delayed fluorescence revealed that the energy transfer depends greatly on the separation between the energy donor and acceptor and that donor-acceptor pairs spaced very closely are important in the energy transfer. In DNA-acridine dye complexes, the thymine triplet seems to play the most important role as an energy donor. The decrease in the delayed fluorescence on the denaturation of DNA indicates that the energy transfer is sensitive to the conformation of the macromolecule.
An ESR Study of Monomeric Cobalt Oxygen Complexes in Solutions
Authors: Koda Seiichiro , Misono Akira , Uchida Yasuzo 
Published: July 2006

Abstract
Several mononuclear cobalt oxygen complexes in solutions have been investigated by means of ESR measurements. When a pyridine (and also substituted pyridines, N,N-dimethylformamide, dimethyl sulfoxide, and hexamethylphosphoramide) solution of a bis-salicylaldehyde-imine cobalt-(II) complex (N,N′-ethylene-bis(salicylideneiminato)cobalt(II), and N,N′-ethylene-bis(3-methoxysalicylideneiminato)cobalt(II)) was exposed to oxygen, there appeared a reversible ESR signal, in which a hf structure of eight lines caused by a mononuclear cobalt was observed. This spectrum could be analysed by considering the species to be essentially a superoxide cobalt(III). We tried to explain the deviations in the ACo and the g values of the species from solvent to solvent by considering that the solvent coodinates to the cobalt complex in the trans position against the coodinated oxygen. As a comparative study, the mononuclear oxygen adduct of di(salicylal)-3,3′-diimino-di-n-propylamine-cobalt(II) was also studied in the above solvents.
The Photometric Determination of Micro Amounts of Bromine in Silicate Rocks by Means of Its Catalytic Effect
Authors: Takahashi Kazuyoshi , Yoshida Minoru , Ozawa Takejiro , Iwasaki Iwaji 
Published: July 2006

Abstract
The catalytic action of bromide on the oxidation of to iodine iodate by potassium permanganate in sulfuric acid solution has been utilized for the microdetermination of bromine in silicate rocks. The method described consists of decomposing the silicate-rock sample by fusion with potassium hydroxide, leaching the melt with water, oxidizing bromide to bromine with potassium permanganate, extracting by benzene, and finally determining the bromine by the catalytic method. By this method, the bromine in samples with more than 0.04 ppm can be determined rapidly and accurately, using only 0.25–0.5 g of samples.
A Spectrophotometric Study of Indoferron as a Color Reagent for Zirconium(IV) and Iron(III)
Authors: Sakai Takayoshi 
Published: July 2006

Abstract
Indoferron is shown to be a useful spectrophotometric reagent for the determination of zirconium(IV) and iron(III). An excess reagent reacts with zirconium(IV) and iron(III) to form blue complexes, which have absorption maxima at 605 and 590 mμ respectively against the reagent blank. The maximum absorbances of the solutions containing the complexes are obtained in the pH range from 3.6 to 3.7 for zirconium(IV), and in that from 3.9 to 4.1 for iron(III). The former complex is stable for 1 hr, and the latter, for 4 hrs. The color systems obey Beer’s law in 25 ml over the ranges up to 40 μg Zr and up to 50 μg Fe respectively. The molar absorptivities of the complexes are calculated to be 3.18 ×104 for zirconium(IV) and 1.81 ×104 for iron(III). The sensitivities of the reactions are 0.0038 μg Zr/cm2 and 0.0039 μg Fe/cm2 for an absorbance of 0.001. As for composition, the complexes used have a metal-to-ligand ratio of 1:3 for zirconium-(IV) and 1:2 for iron(III). The apparent formation constant of the complex for iron(III) is calculated to be 7.81 ×1010.
Tri(hetero)substituted Carbonium Ions. III. Ring-size Effects on the Dual Reactivities of 2-Dimethylamino-1,3-dithiolanylium Ion and Its Ring Analogs as Ambident Electrophiles
Authors: Nakai Takeshi , Ueno Yoshio , Okawara Makoto 
Published: July 2006

Abstract
The following ring analogs of 2-dimethylamino-1,3-dithiolanylium perchlorate (Ia) were prepared: 2-dimethylamino-1,3-dithianylium perchlorate (IV), 2-dimethylamino-1,3-dithiepanylium perchlorate (V) and an open-chain analog, bis(methylthio)dimethylaminocarbonium perchlorate (VI). In order to investigate the structural effect on the reactivities of the tri(hetero)carbonium ions at two reactive sites, i. e., the centered carbon (sp2) (a) and the S-methylene carbon (sp3) atoms (b), the reactions of these carbonium ions with hydroxide ion (mode A) and with N,N-dimethyldithiocarbamate ion (mode B), respectively, were studied at 30°C. The rates of mode A of these carbonium ions, relative to that of Ia, are 1 : 15.0 (IV) : 32.5 (V) : 1.06×104 (VI), and of mode B are 1 : 6.5 : 23.5 : ≈2.0×104. In their electronic spectra a definite trend that as the ring-size increases there is a strong shift of absorption maxima toward the lower energies was observed. The fact suggests that the stability of the carbonium ion decreases with an increase in ring-size. On the basis of the schematic energy profiles for the two modes as well as the structural and kinetical aspects, it has been assumed that one of common factors contributing to the ringsize effect on both reactivities would be the stability of the carbonium ion.
The Carbon-13 NMR Spectra of Alkyl Vinyl Ethers, and Their Structures and Reactivities
Authors: Hatada Koichi , Nagata Kazuhiko , Yuki Heimei 
Published: July 2006

Abstract
The 13C NMR spectra of alkyl vinyl ethers were investigated at 22.5°C with neat liquid at 15.09 MHz. When the alkyl group of the ether becomes more electron-donating, the chemical shift of the α-carbon of the vinyl group shifts to a higher field, and that of the β-carbon, to a lower field. From these results, it was concluded that the contribution of the resonance form, \barCH2–CH=\overset+O–R, in the ether decreases in the order of the increasing electron-repelling power of the alkyl group. Good correlations were obtained between the chemical shifts of the vinyl group and the reactivity of vinyl ether in the cationic reaction. When the ether becomes more reactive, the chemical shift of the α-carbon shifts to a higher field, and that of the β-carbon to a lower field. This fact clearly shows that the attack of the proton on the β-carbon is not the rate determining step in the cationic reaction of the vinyl group. Linear relations were obtained between the chemical shifts of β-methylene protons and of β-carbon, but no correlation was obtained between the chemical shifts of the α-methine proton and of the α-carbon.
Reactions between β-Propiolactone and Dialkyl Dimethylphosphoramidite-Ambident Character of β-Propiolactone and of Dialkyl Dimethylphosphoramidite
Authors: Koketsu Jugo , Kojima Seiji , Ishii Yoshio 
Published: July 2006

Abstract
The reactions between dialkyl dimethylphosphoramidite, Me2NP(OR)2, and β-propiolactone were carried out in various solvents at 80°C. Two kinds of reaction products were separated on a silica gel by elution with benzene-ethanol (4:1 v/v). The first species eluted was N,N-dimethyl-O-alkyl 2-alkoxycarbonylethylphosphoramidate, (RO)P(O)(NMe2)CH2CH2CO2R. The fraction having lower Rf value contained dialkyl 2-N,N-dimethylcarbamoylethylphosphonate, (RO)2P(O)CH2CH2CONMe2. The reaction mechanism is discussed from kinetic study.
Syntheses of Some Derivatives of d-Glucuronic Acid
Authors: Irimajiri Takeshi , Yoshida Hiroshi , Ogata Tsuyoshi , Inokawa Saburo 
Published: July 2006

Abstract
The syntheses of some derivatives of d-glucuronic acid from d-glucofuranurono-6→3-lactone have been investigated. That is, 5-bromo-5-deoxy-1,2-O-isopropylidene-β-l-idofuranurono-6→3-lactone (2) and 5-bromo-5-deoxy-1,2-O-isopropylidene-α-d-glucofuranurono-6→3-lactone (3) were prepared by heating 1,2-O-isopropylidene-5-O-(p-toluenesulfonyl)-α-d-glucofuranurono-6→3-lactone (1) with lithium bromide in dimethylformamide (DMF); methyl 5-O-(p-toluenesulfonyl)-β-d-glucofuranurono-6→3-lactone, 5-bromo-5-deoxy-α-l-idofuranurono-6→3-lactone, and 5-bromo-5-deoxy-β-d-glucofuranurono-6→3-lactone were prepared by heating 1, 2, and 3 respectively in methanol in the presence of strong acidic ion-exchange resins; 5-deoxy-1,2-O-isopropylidene-α-d-glucofuranurono-6→3-lactone (7) was prepared by the reaction of 2 with thiolacetic acid of benzylmercaptan in pyridine or by the reaction of 2 with triethyl phosphite; 5-bromo-5-deoxy-1,2-O-isopropylidene-β-l-ido-hexodialdo-3,6-furanoid(6S)-1,4-furanose (8) was prepared by the reduction of 2 with lithium aluminum hydride; 1,2-O-isopropylidene-5-O-(p-toluenesulfonyl)-α-d-gluco-hexodialdo-3,6-furanoid-1,4-furanose and 1,2-O-isopropylidene-5-O-(p-toluenesulfonyl)-α-d-glucofuranose (10) were prepared by the reduction of 1 with lithium aluminum hydride, and 1,2;3,6-di-O-isopropylidene-5-O-(p-toluenesulfonyl)-α-d-glucofuranose and 3,6-di-O-acetyl-1,2-O-isopropylidene-5-O-(p-toluenesulfonyl)-α-d-glucofuranose were prepared by the acetonation and the acetylation of 10 respectively.
The Crystal and Molecular Structure of Tetrodotoxin Hydrobromide
Authors: Furusaki Akio , Tomiie Yujiro , Nitta Isamu 
Published: July 2006

Abstract
The crystal and molecular structure of the hydrobromide of tetrodotoxin itself, C11H17O8N3·HBr, have been studied by means of three-dimensional X-ray analysis. The crystals are tri-clinic, with two formula units in a unit cell of the dimensions; a=8.79, b=9.02, c=9.51 A, α=106°51′, β=88°1′, and γ=96°23′; the space group is pl. The intensities of reflections were recorded on equi-inclination Weissenberg photographs taken with CuKα radiation around the b and c axes, and were measured visually with a calibrated intensity scale. The structure was elucidated by means of the Fourier and least-squares methods, and was refined by the block-diagonalmatrix least-squares method, the anisotropic thermal motion being assumed only for bromine atoms. The stereostructures of the two crystallographically-independent molecules of tetrodotoxin thus obtained are almost identical and correspond to that deduced by Tsuda et al., by Hirata et al., and by Woodward et al., all in 1964. It is noteworthy that, in both of the two molecules, the C–O distance for the free hydroxyl group in the ortho-ester part (1.36 and 1.39 Å) is somewhat smaller than the ordinary aliphatic C–O distance, 1.43±0.01 Å, and that it is rather closer to the phenolic C–O distance, 1.36±0.01 Å.
Structure of Polynucleotide Complex with Non-Complementary Nucleosides. I. Poly A,G+Poly U
Authors: Akutsu Hideo , Tsuboi Masamichi 
Published: July 2006

Abstract
Copolymers of riboadenylic and riboguanylic acids (poly A,G) with guanylic acid contents of 8.5–29.6% were prepared. The ultraviolet and infrared absorptions were examined of aqueous solutions of mixtures of poly A,G and polyribouridylic acid (poly U) of various mole ratios. It has been shown that in a solvent with 0.1 m Na+ a triple-helical structure is formed with a (Remark: Graphics omitted.) type inter-base binding as well as a double-helical structure with a A···U type binding, while in a solvent with 0.01 M Na+ only double-helical structure is formed. A guanine residue in the copolymer remains within the helix structure when its neighbors are mostly adenine residues, whereas it rotates out when there are many guanine residues in its vicity. On heating the solution, the structures just mentioned were found to be broken. The process of such a breaking down was followed also by means of the ultraviolet and infrared absorption measurements.
Quantum Yield of Photo-rearrangement of Nitrones
Authors: Koyano Kinko , Suzuki Hiroshi , Mori Yuji , Tanaka Ikuzo 
Published: July 2006

Abstract
Fifteen nitrones, N-butylidenecyclohexylamine N-oxide, N-benzylidenemethylamine N-oxide, N-diphenylmethylenemethylamine N-oxide, N-benzylidenaniline N-oxide, and its derivatives, were irradiated with light in solution, each at its longest-wavelength absorption band. Each nitrone isomerized to the corresponding oxazirane. The quantum yield of this photo-rearrangement, Φ, was measured. For each nitrone, the value of Φ is larger in cyclohexane solution than in ethanol solution. In the series of N-benzylidenaniline N-oxide and its para-substituted derivatives, the substituent lowers Φ, and the more electron-donating or the more electron-withdrawing the substituent is, the smaller is Φ. These facts are explained on the basis of a hypothesis that π should increase with the change in the π-bond order between the carbon and oxygen atoms of the nitrone group upon the lowest-energy electron excitation, ΔPC,O, calculated by the simple MO method.
The Polymerization of Vinyl Monomers in the Presence of Surface Active Agents. I. The Polymerization of Methyl Methacrylate
Authors: Asahara Teruzo , Sen\={o} Manabu , Shiraishi Shinsaku , Arita Yoshikazu 
Published: July 2006

Abstract
Methyl methacrylate polymerized in the presence of a surface active agent in an aqueous system without any ordinary initiators. Anionic surface active agents, such as sodium tetrapropylenebenzenesulfonate and sodium 2-dodecylbenzenesulfonate, markedly effected the polymerization of methyl methacrylate in the presence of water. The polymerization was inhibited by adding hydroquinone to the reaction system and was also affected adversely by oxygen. Water as a reaction medium was found to be indispensable. The polymerization in organic solvents afforded hardly any polymeric products.
Studies of Phosphorylation. IV. The Phosphorylation of Nucleosides with Phosphorus Trihalide
Authors: Yoshikawa Masaharu , Sakuraba Mitsuru , Kusashio Koji 
Published: July 2006

Abstract
The treatment of a 2′,3′-O-isopropylidene nucleoside with phosphorus trichloride in the presence of trimethyl phosphate and subsequent hydrolysis gave a nucleoside 5′-phosphite in an excellent yield. Triaryl phosphates, trialkylphosphine oxides, and trialkyl phosphites were also found to be potential accelerators of the reaction. Their effects were comparable to that of trimethyl phosphate. The similar treatment of a 5′-O-acetyl nucleoside gave mixed nucleoside 2′- and 3′-phosphites in an approximate mole ratio of 4 : 6. The reaction intermediate, nucleoside phosphorodichloridite, was subjected to partial hydrolysis, giving the corresponding monochloridite. The product was readily oxidized to give the 5′-nucleotide. Chlorine was generally suitable as an oxidizing agent, but iodine gave better results for guanosine derivatives than did chlorine or bromine. The treatment of an unprotected nucleoside with phosphorus oxychloride in a trialkyl phosphate, prior to the reaction with phosphorus trichloride, could be used for the synthesis of a nucleoside 2′(or 3′),5′-diphosphate in a good yield.
A-Substituted 5β-Steroids. III. Synthesis of 2-Oxo- 5β-steroids and Their Derivatives
Authors: Satoh Yasuo , Horiuchi Akira , Hagitani Akira 
Published: July 2006

Abstract
The synthesis of 2-oxo- 5β-steroids (5β-cholestan-2-one and methyl 2-oxocholanate) and their derivatives have been described. Both oxo-steroids were prepared from 2β-acetoxy-3-oxo- 5β-ste-roids according to the following synthetic pathways: (a) condensation with ethylmercaptan to diethylmercaptol, desulfurization, hydrolysis and oxidation, (b) condensation with ethylmercaptan to diethylmercaptol, hydrolysis to hydroxy-ethylmercaptol, desulfurization and oxidation, and (c) isomerisation to 3α-acetoxy-2-oxo derivative and deacetylation with zinc powder to 2-oxo derivative. In these pathways, it was found that method (b) gave the best yield. On the other hand, desulfurization of the hydroxy-mercaptols with one-half the weight of Raney nickel used for that of method (b) gave 2β-hydroxy- 3β-ethylthio derivatives as intermediates. Reductive cleavage of these hydroxy-ethylthio derivatives with Raney nickel produced 2β-hydroxy- 5β-steroids in good yields. In the halogenation of these 2-oxo derivatives, the products were 1β-halo-2-oxo- 5β-sterodis, not 1α- or 3-halo isomers.
The Kinetics of the Chromic Acid Oxidation of Phenylphosphonous Acid
Authors: Sen Gupta Kalyan K 
Published: July 2006

Abstract
The kinetics of the oxidation of phenylphosphonous acid by chromic acid has been investigated. The rate at which gross concentration of chromium (VI) disappears follows a first order law. The rate increased with the increase of hydrogen ion concentration. The activation energy of the reaction was found to be 7.4 kcal. The effect of pyridine on the reaction rate confirmed the findings of Westheimer who showed that pyridine catalyzes the oxidation of isopropyl alcohol. It is suggested that the oxidation appears to proceed through the initial formation of an intermediate compound between the active form of phenylphosphonous acid with chromic acid which finally decomposes slowly by the rate determining step. The inactive form is finally oxidized by chromium(V) by very fast step.
Kinetic Investigations of the Reaction of Brilliant Green with Alkalies. Influence of Ionic Strength
Authors: Katiyar Sarvagya S 
Published: July 2006

Abstract
Kinetic studies of the reaction of brilliant green with alkalies have been made by following the reaction spectrophotometrically at 625 mμ. The reaction has been found to be bimolecular but under experimental condition of excess alkali, it obeyed a first order law. The rate constants was independent of the concentration of brilliant green but it varied linearly with the hydroxyl ion concentration. Effect of neutral salt on the rate of reaction was investigated in aqueous and in 40% acetone-water media. The rate was found to decrease progressively with increasing ionic strength in both media. Analysis of the data by Brφnsted-Christiansen-Scatchard equation yielded a value of −1 for ZaZb indicating thereby that the rate-determining step involves oppositely charged species possessing unit charge. The value of inoic interaction parameter, ai corresponded to 1.5 and 4.75 Å in aqueous and 40% acetone-water medium respectively. Without attaching too precise a meaning to ai it is suggested that B.G. ion is presumably solvated to a greater extent in 40% acetone-water than pure water.