bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and Biological Activity of Peptides Related to Eledoisin. I. Hexapeptide Amides Containing α-Hydroxy Acids
Authors: Sugano Hiroshi , Higaki Ko , Miyoshi Muneji 
Published: July 2006

Abstract
A new series of eledoisin-like depsipeptides was synthesized in order to obtain some information about the relationship between the structure of the peptide backbone of eledoisin and the biological activity. Specific amino acids in the biologically-active hexapeptide analog of eledoisin, H–Lys–Phe–Ile–Gly–Leu–Met–NH2 (1), were replaced by the corresponding α-hydroxy acids. The biological activities of these analogs were then compared with that of the standard one (1). On the blood pressure in rabbits, H–Lys–Phe–Ile–Glyc–Leu–Met–NH2 (4) and H–Lys–Phlac–Ile–Gly–Hylc–Met–NH2 (6) possessed a substantial activity, though lower than 1, and H–Lys–Phlac–Ile–Gly–Leu–Met–NH2 (2) and H–Lys–Phe–Ile–Gly–Hylc–Met–NH2 (5) were almost as active as 1. On the other hand, H–Lys–Phe–HyMeV–Gly–Leu–Met–NH2 (3) exhibited much less activity. The results indicate that the amide bond between the phenylalanine residue and the isoleucine residue is essential for the hypotensive activity.
Distribution of Uranyl Nitrate between 1- or 2-Butanol and Aqueous Phases
Authors: Yui Norio , Kurokawa Y\={o}ichi , Fujita Taketoshi 
Published: July 2006

Abstract
The distribution of uranyl nitrate between 1- or 2-butanol and aqueous phases and the effect of nitric acid or sodium nitrate on the distribution at 25°C have been studied. Conductance measurements have been carried out for the butanol solutions of uranyl nitrate. It was found that high water content in the butanol phase gives rise to the dissociation of the salt. Semi-empirical relations hold for the distribution considering the dissociation of salt in the butanol phase. Observed and calculated slopes agree in the plots of distribution ratio vs. nitrate concentration. The results were discussed in comparison with distribution data in literature.
Syntheses of Decadiendiyndials and Tetradecatetraendiyndials and Intramolecular Cyclization of Former Dialdehydes
Authors: Muneyuki Ryonosuke , Morimoto Mamoru , Tanaka Motomu , Katakami Tsutomu , Kashitani Takayoshi , Iyoda Masahiko , Nakagawa Masazumi 
Published: July 2006

Abstract
Substituted 2,8-decadien-4,6-diyndials (I, II and III) were synthesized by the oxidative coupling of corresponding substituted pentenynals (VII and XIII) or acetal (XI). It was found that decadiendiyndials (I, II and III) give readily dihydrofuranylidene derivatives (X, XIV and XXV) by the addition of methanol followed by intramolecular cyclization. Thermal reaction of dialdehyde (I, II, and III) afforded difuranylacetylene derivatives (IX, XXI and XXII). 5-Phenyl-2,4-heptadien-6-ynal (XXXII) was prepared from 3-phenyl-2-penten-4-ynal (VIII) or its acetal (XI) by a modified Wittig reaction or by the condensation of ethyl vinyl ether. Oxidative Coupling of XXXII or 5-t-butyl-2,4-heptadien-6-ynal afforded 5,10-diphenyl-(XXIX) or 5,10-di-t-butyl-2,4,10,12-tetradecatetraen-6,8-diyndial (XXX) which showed no tendency for intramolecular cyclization.
An X-Ray Study of Coal Tar Pitch
Authors: Shiraishi Minoru , Kobayashi Kazuo 
Published: July 2006

Abstract
The diffuse X-ray scattering from coal tar pitch has been investigated by using Fourier transformation for the 002 band and Diamond’s least-squares method for the 11 band. From the results of this investigation, the layers were found to be stacked parallel to each other, partly in groups of 8–9 layers, the average number of the layers being 2.46. The distribution of the layer size showed a peak at the diameter of 8.4–10 Å, the average layer size was 8.9 Å, which corresponded to 25 atoms per layer.
The Primary Process of the Photochemical Dimerization of Carbostyril (2-Quinolone) in an Aqueous Solution
Authors: Yamamuro Tetsu , Hata Norisuke , Tanaka Ikuzo 
Published: July 2006

Abstract
Carbostyril dimerizes photochemically in an aqueous solution, in order to investigate the effect of a hydroxide ion on the primary process of the photochemical dimerization in an aqueous solution, both measurements of the quantum yields and flash spectroscopic experiments were carried out under various conditions. The experiments revealed that the photodimerization reaction proceeded through a bimolecular interaction between the triplet and the unexcited carbostyril molecules, although the triplet carbostyrilate ion was in equilibrium with the triplet carbostyril. The triplet carbostyrilate ion was proved not to be involved in the dimerization process.
The Crystal Structure of an N-Methylphenothiazine–7,7,8,8-Tetracyanoquinodimethane Complex, N-MePZT–TCNQ
Authors: Kobayashi Hayao 
Published: July 2006

Abstract
Crystals of the 1 : 1 charge-transfer complex of N-MePZT–TCNQ, are monoclinic with those lattice constants: a=10.904, b=13.321, c=7.086 Å, and β=91.06°, and with the space group C2/m. X-ray structure analysis showed that the mixed-stacks of N-MePZT and TCNQ, exist along the c axis. N-MePZT is disordered, and its apparent molecular symmetry is C2h, taking four possible conformations. The molecular geometry of TCNQ, indicates that the amount of the charge transferred from N-MePZT is very small (&lt;0.2e).
Studies on Nitrile Salts. III. Dimerization of Nitriles Having No α-Hydrogen with Hydrogen Chloride
Authors: Yanagida Shozo , Fujita Tetsuo , Ohoka Masataka , Katagiri Ichiro , Miyake Mikio , Komori Saburo 
Published: July 2006

Abstract
The reaction of nitriles having no α-hydrogen, such as aromatic nitriles and thiocyanates, with hydrogen chloride was investigated. Benzonitrile, p-tolunitrile, m-tolunitrile and some thiocyanates gave analytically pure 2:2 adducts in their reactions with HCl in a sealed glass tube at 30–60°C. The structure of the adducts was elucidated on the basis of NMR analysis and the mechanism of the generalized dimerization of nitriles was discussed.
Studies on Nitrile Salts. IV. Trimerization of Nitriles to 1,3,5-Triazines by the Combined Catalyst PCl5–HCl
Authors: Yanagida Shozo , Yokoe Masaaki , Katagiri Ichiro , Ohoka Masataka , Komori Saburo 
Published: July 2006

Abstract
The combined catalyst PCl5–HCl shows effective catalysis in the trimerization of some aromatic nitriles or trichloroacetonitrile to s-triazines (III). The scope and limitation of the trimerization, in comparison with other Lewis acids, and its mechanism were studied. It was confirmed that PCl5 is effective both in the formation of an intermediate, nitrile–HCl 2:2 adduct, and in the reaction of the 2:2 adduct with another nitrile to s-triazine.
ESR Line Width and Exchange Narrowing in Powder Samples
Authors: Misra B N , Gupta S K 
Published: July 2006

Abstract
Electron Spin Resonance Spectra of 1-1 Diphenyl-2-Picryl Hydrazyl (DPPH) recrystallized from some aliphatic and aromatic solvents have been studied at room temperature in the X-band region. Measurements of lineshape, linewidth and g value were carried out, all the samples being subjected to microchemical analyses with determination of density and melting point. A theoretical study of ESR linewidths has been carried out by means of the Kubo-Tomita theory of ESR linewidth. A quantitative estimation of dipolar width, exchange frequency, exchange integral and asymptotic Curie temperature for each sample was made. A reduction of exchange narrowing has been suggested to be the main cause of broadening.
Thermometric Titration in the Investigation of the Formation of Polyanions of Molybdenum(VI), Tungsten(VI), Vanadium(V), and Chromium(VI). III. Titration of Molybdic Acid with Sodium Hydroxide Solution
Authors: Kiba Nobutoshi , Takeuchi Tsugio 
Published: July 2006

Abstract
To define the properties of molybdenum-containing species which appear in the acidification of neutral molybdate solution with mineral acid, the reverse process, i.e. the titration of molybdic acid of acidified molybdate solution with sodium hydroxide, was examined and the titration curves were obtained thermometrically as well as potentiometrically. In the thermometric titration curves there are inflections not found on the pH-titration curves of the same systems. Titration curves of both methods change with molybdenum concentration, the reaction process being found to be responsible for the change. Polymolybdate anions were identified with the aid of the ultraviolet spectrophotometry of Punger et al. A neutral salt such as sodium perchlorate or lithium perchlorate was found to affect the shape of the thermometric titration curve, since in the presence of such salt octamolybdate ion was readily converted into heptamolybdate ion.
Liquid Crystalline Properties of Substituted Azo- and Azoxy-benzenes. I
Authors: Murase Kei , Watanabe Haruaki 
Published: July 2006

Abstract
In order to obtain low-temperature mesomorphic materials, thirty-two p-alkyl-p′-alkoxy-azo- and -azoxybenzenes have been synthesized. The former have been made by the condensation of p-n-alkylnitrosobenzenes and p-n-alkoxyanilines, and the latter, by the oxidation of the former. Twenty-nine of the compounds show nematic behavior. In the majority of cases, the nematic temperature range of the azoxy compounds, which have been considered to consist of two isomers synthesized simultaneously, is appreciably wide.
The Catalytic Effect of Bases on the O→N Migration of the s-Triazinyl Group in O-(s-Triazinyl)-2-aminophenols
Authors: Shiojima Takeo , Hashida Yoji , Matsui Kohji 
Published: July 2006

Abstract
The catalytic effect of bases on the O→N migration of the s-triazinyl group in O-(s-triazinyl)-2-aminophenols has been studied kinetically. In the rearrangement of N-(acyl)-O-(s-triazinyl)-2-aminophenols (II) in alkaline aqueous methanol, the reactive species was found to be an ion formed by the ionization of the acylamino group. In the case of O-(s-triazinyl)-2-aminophenols (I), the rearrangement was subjected to a general base catalysis, although the extent was small.
Polycondensation of Malononitrile and Methylenedimalononitrile with Bis(chloromethyl)Aromatic Compounds Using Triethylamine as Acid Acceptor
Authors: Kawabata Nariyoshi , Matsubara Kenichi , Yamashita Shinzo 
Published: July 2006

Abstract
Malononitrile was found to undergo condensation reaction with benzyl chloride to give dibenzylmalononitrile in a quantitative yield under mild conditions when an organic base such as triethylamine was used as acid acceptor in dimethyl sulfoxide. The reaction was applied to the polycondensation of malononitrile and methylenedimalononitrile with p-xylylene dichloride and p,p′-bis(chloromethyl)diphenyl ether, polymers with intrinsic viscosity 0.14–0.22 dl/g being obtained in quantitative yields.
Compounds Relating to Dibenzoyladenine Riboside. The Choice between the N6,1-Dibenzoyl and N6,N6-Dibenzoyl Structures
Authors: Anzai Kentaro , Matsui Masanao 
Published: July 2006

Abstract
It was clarified, by NMR analysis and on the grounds of synthetic work, that dibenzoyladenine riboside and its analogues have the N6,N6-dibenzoyl structure rather than the N6,1-dibenzoyl structure, which has customarily been used to describe the benzoyl derivatives of adenosine.
A Note on the Intermolecular Orthogonalized Orbital
Authors: Kato Hiroshi , Ishimaru Shingo 
Published: July 2006

Abstract
The procedure for treating the molecular interaction is simplified by using the intermolecular orthogonalized orbital given by the method of Löwdin, and the accuracy of the approximation is examined, giving examples of the proton spin density of the solvated electron and the delocalization energy between chemically-interacting molecules. The following is then concluded: the intermolecular orthogonalized orbital is a kind of perturbed wavefunction of the molecule interacting with the other system and can most reasonably be applied when the Mulliken-type approximation for the intermolecular integrals can well be used. Its utility with regard to the three-system problem is also briefly discussed.
Mixed Ligand Complex Formation between Monodentate Ligands and Various Tridentate Ligand-Copper(II) Complexes
Authors: Yamauchi Osamu , Benno Hiroshi , Nakahara Akitsugu 
Published: July 2006

Abstract
Formation of mixed ligand complexes between monodentate ligands (L) and copper(II) complexes of tridentate ligands (A) has been investigated by potentiometric titration and thermal analysis. Thus, the constants, logKm, for the formation of the complexes of type CuA·L from CuA and L have been calculated from the titration curves by the method of non-linear least-squares. A refers to diethylenetriamine, dipicolylamine, 2,2′,2″-terpyridine, ethylenediamine-N-monoacetic acid, iminodiacetic acid, or pyridine-2,6-dicarboxylic acid and L to pyridine, p-phenolsulfonic acid, n-butylamine, or hydroxy group. The stability series in each system with L fixed has been interpreted in terms of the strength of A as a Lewis base, expressed by the sum of pKa (ΣpKa), as well as back-donation. In the absence of significant steric hindrance, favorable combination of donor atoms around copper(II) has been found to be between aromatic nitrogens and negative oxygens. Thermal stability of the isolated complexes of type CuA·PY, where PY is pyridine, was also in line with the stability sequence in solution.
Carboxylation of Phenol Derivatives. XXI. The Formation Reaction of the Complex from Alkali Phenoxide and Carbon Dioxide
Authors: Hirao Ichiro , Kito Taketoshi 
Published: July 2006

Abstract
The yield of the complex was examined using eleven potassium phenoxide or substituted phenoxides. The phenoxide with an electron-donating group gave a complex in a better yield than did that with an electron-attracting group. The infrared spectra of the four complexes were measured. From these results, it was concluded that, in the complex, the carbon atom of carbon dioxide binds to the oxygen atom or the π-electron of alkali phenoxide. The thermal analyses of the complex were also conducted by DTA and TGA in an atmosphere of carbon dioxide; a strong endothermic peak and a rapid weight loss were observed at the temperatures from 120 to 140 °C.
The Activation of Bivalent Sulfur Compounds with Cupric Chloride and Zinc Chloride. The Benzylation and Acylation of Aromatic Compounds with Sulfides and Thiol Esters
Authors: Maekawa Kazuo , Narasaka Koichi , Mukaiyama Teruaki 
Published: July 2006

Abstract
Benzylation of aromatic compounds, such as anisole, m-xylene, toluene, and benzene, with various benzyl sulfides in the presence of equimolar amounts of cupric chloride and zinc chloride was investigated. For example, in the case of benzylation of anisole with 4-benzylthiopyridine, o- and p-benzylanisoles were obtained in 79% yield in the presence of cupric chloride and zinc chloride. On the other hand, when the reaction was carried out in the presence of cupric chloride alone, the yield of benzylanisoles was low. The similar activation with cupric chloride and zinc chloride was successfully applied to the reaction of aromatic compounds with benzaldehyde diethylthioacetal and to the acylation of aromatic compounds with 1,2-bis(acylthio)ethanes.
Kinetic Study of the Pyrolysis of 1- and 2-Phenylethyl Phenyl N-Tosylsulfilimines
Authors: Oae Shigeru , Harada Katsumasa , Tsujihara Kenji , Furukawa Naomichi 
Published: July 2006

Abstract
The pyrolysis of 1-phenylethyl phenyl N-tosylsulfilimine was found to proceed more than 103 times faster than that of ethyl phenyl derivative. The large rate enhancement suggests that the mechanism changes from an ideal cis-elimination to nearly El type. However, substituent effect, kinetic isotope effect with 1-phenylethyl-2,2,2-d3 phenyl N-tosylsulfilimine and solvent effect clearly reveal that the reaction proceeds via an intramolecular concerted process.
Optical Resolution and Stereochemistry of γ-Hydroxyglutamic Acid
Authors: Lee Yong Kyun , Kaneko Takeo 
Published: July 2006

Abstract
Four optical isomers of γ-hydroxyglutamic acid were prepared in pure states by optical resolution of two racemic diastereoisomers through brucine salt of N-benzyloxycarbonyl amino acid or strychnine salt of N-benzoyl derivative. Configurations of α- and γ-asymmetric carbon atoms of these isomers were estimated from contribution to molecular rotation and character of taste exhibition. These determinations were confirmed by chemical degradations to aspartic acid and malic diamide of the definite configurations. Cyclization of each racemic diastereomer to either lactone or lactam was also investigated.
Stereochemistry of the C and D Rings of C-Nor-D-homosteroids. I. The Birch Reduction of “Jervine-11β-ol” and Related Compounds
Authors: Murai Akio , Arita Keiko , Masamune Tadashi 
Published: July 2006

Abstract
The Birch reduction of “jervine-11β-ol” (4) was reinvestigated in detail. Two unknown (6 and 7) and two known compounds (8 and 9) with established configurations were newly isolated besides the previously obtained products (2 and 5). The main product (2), the C17 configuration of which has been left undefined, was degraded into a methyl ketone (18) via a known saturated compound (14) (Chart 2) or correlated with an α,β-unsaturated ketone (23) (Chart 3). These transformations confirmed the configuration of 2 (C17–H) to be β, since the steric structures of compounds 18 and 23 have been determined in an unambiguous manner. On the other hand, the structures and configurations of 6 and 7 were elucidated as shown by the formulas on the respective spectral data as well as by hydrogenation of 6 to 14 (Chart 4) and by hydrolysis of an 11β-alcohol (24=7a), obtained by reduction of the ketone 23, to 7 (Chart 4). These results together with those of the Birch reductions of 11-deoxojervine (1) and product 7 are summarized as follows: Products 2, 6, 7, and 9 with the saturated 17-carbon all take the β-hydrogen configuration at C17, products 3 and 5 with the C13–C17 double bond the α-hydrogen configuration at C12, and products 8 and 9 with the saturated carbons at C13 and C17 the β-hydrogen configuration at C12.
Oxidation of Carbon Monoxide over Transition Metal Ion-Zeolite Catalysts
Authors: Kubo Toshihiko , Tominaga Hiroo , Kunugi Taiseki 
Published: July 2006

Abstract
Adsorption of oxygen and oxidation of carbon monoxide was investigated on several X and Y type zeolites, their Na+ being replaced by transition metal ions. Oxygen adsorption was observed on Cr(II), Cu(I), and Fe(II) ions whose oxidation potentials are high, giving an oxygen atom to metal ion ratio of 0.43–0.62 or nearly 0.5. A small amount of oxygen was adsorbed on Tl(I), Co(II), and Mn(II), as expected from their standard oxidation potentials. No oxygen was adsorbed on Cu(II) and Ni(II), their valences being difficult to increase. The activities of these transition metal ions for oxidation of carbon monoxide increased exponentially with the increase of their standard oxidation potential. Kinetic studies on CO oxidation over Fe(II)–X and –Y zeolites have been made, and a Rideal mechanism is suggested where CO molecules in the gas phase attack the oxygen atoms dissociatively adsorbed in the bridged form of Fe3+–O2–Fe3+. The difference in the activities of Fe(II)–X and –Y catalysts is discussed.
Studies on Fragment Ion Distribution and Reaction with a Charge Spectrometer. V. Applicability of the MO Theory to the Fragmentation of Alkanes by Charge Exchange
Authors: Ikuta Shigeru , Yoshihara Kenji , Shiokawa Takanobu 
Published: July 2006

Abstract
The relation between the fragment ion distribution and recombination energy of the incident positive ions was studied by means of charge exchange reactions. The energy range which is consistent with the molecular orbital (MO) theory proposed by Hirota to account for the mass spectra by electron impact was also investigated, and the usefulness of the theory was discussed. The energy range to which the MO theory is applicable is very limited, the fragment ions produced at the high recombination energy to which it is apparently applicable, being the C2, C3 and C1 ion groups. It is probable that these species are not produced directly from the parent but by degradation mechanisms via intermediate steps, thus causing disagreement with the MO theory. Its applicability to alkanes is open to question. The dissociation schemes on n-alkanes are presented from the expreimental results.
Transport Properties of Multi-component Polar Gas Mixtures Containing Mono-, Di-, and Trimethylamines
Authors: Naser P 
Published: July 2006

Abstract
The viscosity and thermal conductivity coefficients of monomethylamine (MMA), dimethylamine (DMA), and trimethylamine (TMA), and their binary mixtures have been measured in the temperature range 25–250 °C. In addition, determinations of thermal conductivity of ternary mixtures at 33 and 88 °C and of several quaternary mixtures (with ammonia) at 33 °C have been made. The results are discussed in the light of modern kinetic theory of gases. Finally, the coefficients of self-diffusion and mutual diffusion in binary mixtures of these gases are estimated from the experimental viscosity results.
An Optical Absorption Study of the Reaction of Bis(O,O′-diethyldithiophosphato)oxovanadium(IV) with Pyridine
Authors: Sato Mitsuo , Kwan Takao 
Published: July 2006

Abstract
The interaction of bis(O,O′-diethyldithiophosphato)oxovanadium(IV), VOdtp2, with pyridine has been studied in toluene by means of the optical absorptions. It has been found that the visible absorption band characteristic of VOdtp2 was shifted toward longer wavelengths upon the formation of the complex species identified as VOdtp2·Py and VOdtp2·Py2. The equilibrium constants and enthalpy and entropy changes for the formation of VOdtp2·Py were determined from the spectral characteristics, measured as a function of the solvent composition and the temperature. The results obtained were then discussed in comparison with those for the base addition of other oxovanadium complexes.
Spectrophotometric Study on the Extraction of Magnesium(II)–8-Hydroxyquinoline-5-sulfonic Acid Chelate Anion with Zephiramine
Authors: Sugawara Masao , Kambara Tomihito 
Published: July 2006

Abstract
The ion-pair of magnesium(II)–8-hydroxyquinoline-5-sulfonic acid chelate anion with zephiramine (Z+Cl−) was extracted into chloroform. The ternary complex has an absorption maximum at 390 nm in the organic layer. The optimum pH range for the extraction is 10.1–11.4. For the first extract, Beer’s law holds for 4.6–20.6 μg of magnesium(II) in 10-ml organic layer, the molar absorptivity being 6.73×103 cm−1 mol−11. The composition of the ternary complex is estimated to be [Mg2+(QS2−Z+)2(HQS−Z+)]o. The extraction equilibrium is given by
Mg^2++3[(HQS^-Z^+)]_o+2OH^-\ightleftharpoons[Mg^2+(QS^2-Z^+)_2(HQS^-Z^+)]_o+2H_2O
where QS denotes 8-hydroxyquinoline-5-sulfonic acid and o the organic phase. The equilibrium constant K is given by logK=16.95±0.13.