bluuebunny/crossref_metadata_2025 huggingface dataset:
Condensations of 1,4-Cyclohexanediones and Secondary Aromatic Amines. II. N-Phenylation of Diarylamines
Authors: Haga Kazuo , Iwaya Katsumasa , Kaneko Ryohei
Published: July 2006

The condensations of 1,4-cyclohexanedione with several diphenylamines were investigated in order to determine the limit of the utility of this reaction for the N-phenylation of aromatic secondary amines. 4-Methoxy-, 4,4′-dimethyl-, and 4,4′-dibromodiphenylamines produced their N-phenylated compounds in fairly good yields, but 4-hydroxy-, 3-methoxy-, and 4,4′-bis(dimethylamino)diphenylamines produced poor yields. Nitro-substituted diphenylamines gave N-phenyl derivatives in low yields along with N-4-hydroxyphenyl derivatives. N,N′-Diphenyl-p-phenylenediamine and N,N′-diphenylbenzidine gave corresponding tetra-N-phenyl diamines in good yields. The condensation of N-phenyl-1-naphthylamine, N-phenyl-2-naphthylamine, di-2-pyridylamine, phenothiazine, and carbazole with 1,4-cyclohexanedione were also examined.
(Z)- and (E)-4,4-Dimethyl-5-oxo-2-pentenoic Acids and Their Derivatives
Authors: Ito Kunio , Miyajima Shingo
Published: July 2006

(Z)-4,4-Dimethyl-5-oxo-2-pentenoic acid (1) exists almost exclusively in the hydroxy lactone form, the tautomeric equilibrium constant (K=[Ring]/[Chain]) being 2.8×103 in water as estimated by the pKa method. Several examples are described of preference for ring forms of derivatives of 1, which are capable of exhibiting ring-chain tautomerism. (E)-4,4-Dimethyl-5-oxo-2-pentenoic acid (7) reacts with thionyl chloride to afford a trimeric chloro lactone, which on treatment with water or aniline gives the corresponding hydroxy or anilino lactone. Compound 1 or 7 reacts with a variety of phenylhydrazines to yield dihydropyrazole derivatives, except for 2,4-dinitrophenylhydrazine which on reaction with 1 gives a 2,4-dinitrophenylhydrazino lactone.
Dynamic Ivestigation of Aqueous Solutions of 2-t-Butoxyethanol and 3-Methoxy-3-methyl-1-butanol by Ultrasonic Methods
Authors: Nishikawa Sadakatsu , Shinohara Ryutaro , Tanaka Goro
Published: July 2006

Ultrasonic absorption in the frequency range of 6.5 to 220 MHz has been measured in aqueous solutions of 3-methoxy-3-methyl-1-butanol and 2-t-butoxyethanol as a function of the concentration along with the measurement of sound velocity at 1.92 and 2.5 MHz at 25°C. A single relaxational ultrasonic absorption has been found in both solutions and it is interpreted by a reaction kinetics associated with the interaction between solute and solvent, AB \ightleftharpoons A+B where AB is the complex, A the solute and B the solvent. The forward and backward rate constants for the interaction have been determined from the concentration dependence of the relaxation frequencies to be kf=1.4×108 s−1 and kb=1.1×108 mol−1 dm3 s−1 for 3-methoxy-3-methyl-1-butanol solution and kf=9.0×107 s−1 and kb=1.3×108 mol−1 dm3 s−1 for 2-t-butoxyethanol solution. The water structure has also been estimated from the absorption data and it has been clarified for the water structure promoted by additions of such solutes. Correlations between the structures of the solutes and the ultrasonic properties of the solutions are discussed in terms of the hydrophobicity of the solutes.
Formation of NH(A3Π) by Electron-Impact Dissociation of Isothiocyanic Acid
Authors: Tokue Ikuo , Ito Yoshio
Published: July 2006

Emission spectra of the fragments of Isothiocyanic acid (HNCS) produced by electron impact were studied. The onset for formation of NH(A3Π) is 9.2±0.5 eV. On the basis of the excitation function of the NH(A–X) band, NH(A) is shown to be formed via a spinforbidden process HNCS→NH(A3Π)+CS(X3Σ+) near the onset. At higher energies, a spin-allowed process HNCS→NH(A)+CS(a3Π) seems to be predominant. The ratio of the formation rate of NH(c) to that of NH(A) is 0.18±0.03.
Electronic Spectra of Two Polymorphs of (5-Dimethylamino-2,4-pentadienylidene)dimethylammonium Perchlorate
Authors: Sano Norimichi , Tanaka Jiro
Published: July 2006

Reflection spectra were measured on two polymorphs of (5-dimethylamino-2,4-pentadienylidene)dimethylammonium perchlorate in order to determine the origin of the J band. One polymorph exhibited two bands with different polarization characteristics; one of them is explained by the molecular-exciton (MX) band of a ππ* transition character and the other is an intermolecular charge-resonance (CR) band, the polarization being along the direction connecting the nitrogen atoms of the adjacent molecules. The other polymorph exhibited a quasi-metallic reflection due to the overlapping of the CR and MX bands.
Vibrational Correction for Methylamine and Determination of the Zero-Point Average Structure
Authors: Iijima Takao
Published: July 2006

The method of vibrational corrections for a molecule which has a large amplitude intramolecular motion has been revised and applied to the determination of the zero-point average structure of methylamine. Necessity of torsional correction for this type of molecules has been pointed out and the method has been presented. A recent result of electron diffraction was jointly used with the effective moments of inertia obtained by microwave spectroscopy by Takagi and Kojima. The structural parameters in rz and \varphiz with the estimated limits of error in parentheses are: r(C–N)=1.471(3) Å, r(C–H)=1.101(3) Å, r(N–H)=1.019(6) Å, ∠HCH=108.4(5)°, ∠HNH=106.0(6)°, and ∠CNH=111.5(7)°. Deuterium isotope effects in the structural parameters were also determined.
Polymer-Supported Diaryl Selenoxide and Telluroxide as Mild and Selective Oxidizing Agents
Authors: Hu Nan Xing , Aso Yoshio , Otsubo Tetsuo , Ogura Fumio
Published: July 2006

Polystyrene-bound diaryl selenoxide and telluroxide have been prepared, which behaved as mild oxidizing agents for thiols to disulfides, phosphines to phosphine oxides, hydroquinone and catechol to p- and o-benzoquinones, and thioketones to oxo compounds. The telluroxide completed these reactions in shorter periods or under milder conditions than the selenoxide. In addition, they effected novel solvent-dependent reactions of thioamides involving thioureas to 1,2,4-thiadiazoles or to nitriles. In nonacidic solvents, the dehydrosulfurization to nitriles occurred in preference to the oxidative dimerization to 1,2,4-thiadiazoles, but an acidic solvent such as acetic acid promoted the latter reaction.
Electrocatalysis in Metal Hydride Electrode. II. Hydrogen Electrode Reaction and Related Properties of Group-IB Metal-Coated LaNi5 Electrodes
Authors: Machida Ken-ichi , Enyo Michio , Adachi Gin-ya , Sakaguchi Hiroki , Shiokawa Jiro
Published: July 2006

Hydrogen storage type electrodes were fabricated from LaNi5 powder after coating with group-IB metals by an electroless plating method, followed by press moulding. The hydrogen electrode reaction (HER) characteristics and mechanical stability during hydrogen charge/discharge cycles were then studied in 1.0 M (M= mol dm−3) NaOH.
Synthesis of 3-Substituted Indoles by a Palladium-Assisted Reaction
Authors: Kasahara Akira , Izumi Taeko , Murakami Satoshi , Yanai Hiroshi , Takatori Masayuki
Published: July 2006

In the presence of palladium(II) chloride, 2-bromoanilines readily react with the methyl vinyl ketone and the ethyl acrylate to produce vinylogous arylamino ketones and esters. A palladium(0)-assisted cyclization of the arylamino ketones and the esters leads to a formation of 3-substituted indoles.
Application of Electron Spectroscopy for Chemical Analysis to Studies of the Composition of Icosanoic Acid Monolayer
Authors: Kobayashi Koichi , Takaoka Kyo
Published: July 2006

Electron spectroscopy for chemical analysis (ESCA) was used to determine the composition of icosanoic acid (n-C19H39COOH) monolayer deposited on the microscope glass slide from the water surface containing Cd2+ at varying pH. It was found that the monolayers deposited from substrate at pH<4.6, pH>6.6, and pH=4.6–6.6 consist of icosanoic acid, cadmium icosanoate, and mixture of both substances, respectively.
Influence of Higher Alcohols on Acid-Catalyzed Hydrolysis of Sodium Dodecyl Sulfate. Effect of Complex Formation
Authors: Nakagaki Masayuki , Yokoyama Shoko
Published: July 2006

The order of effectiveness of 1-alkanols for increasing the rate of acid-catalyzed hydrolysis of sodium dodecyl sulfate is 1-dodecanol>1-tetradecanol >> 1-decanol. The effect of 1-alkanols on this hydrolysis is discussed from the viewpoint of formation of complexes composed of SDS and 1-alkanol.
Spectrophotometric Determination of Nickel with Sarcosinexylenol Blue
Authors: Ueda Joichi , Fukazawa Yukiko , Koizumi Yuu
Published: July 2006

Sarcosinexylenol Blue (SXB) was synthesized and the possibility of using SXB as a spectrophotometric reagent was examined. The fundamental conditions for the photometric determination of nickel which gave relatively strong coloration with SXB were studied. The simultaneous determination of nickel and zinc was also studied.
Color Reaction among Pyrogallol Red, Thorium(IV) and Samarium(III), and Its Application to the Determination of These Metals
Authors: Mori Itsuo , Fujita Yoshikazu , Fujita Kinuko , Kitano Shoko , Ogawa Itsuko , Kawabe Hiroshi , Koshiyama Yozo , Tanaka Takeshi
Published: July 2006

The color reactions between Pyrogallol Red(PR) and thorium(IV), and also those among PR, thorium(IV) and samarium(III) were studied. Simple and sensitive spectrophotometric determinations of these ions were newly carried out in the range for 1–22 μg/10 cm3 of thorium (IV) and 0.5–10 μg/10cm3 of samarium(III) at 635 nm by using the PR–Th–Sm ternary complex.
The Solvent-Mode Effect on the Resonance Raman Excitation Profiles of Lycopene
Authors: Saito Mineo , Mikami Yasushi
Published: July 2006

The solvent-induced broadening mechanisms are considered in the calculation of resonance Raman excitation profiles (RREP) for the ν1 and ν2 vibrational modes of lycopene. The broadening mechanisms are classified into two groups: Inhomogeneous broadening due to a distribution of the 0-0 transition energies and solvent-induced homogeneous broadening due to coupling with low-frequency solvent-solute interactions. The conventional sum-over-states formula for RREP is transformed to a formally equivalent expression in the time domain. The results show that the homogeneous broadening dominates the RREP of lycopene.
Selective Preparation of Fluorene Derivatives Using the t-Butyl Function as a Positional Protective Group
Authors: Kajigaeshi Shoji , Kadowaki Toshiya , Nishida Akiko , Fujisaki Shizuo
Published: July 2006

Several 4-substituted 2,7-di-t-butylfluorene derivatives (3) were prepared by electrophilic substitutions of 2,7-di-t-butylfluorene (1). 4-Substituted fluorene (4), such as 4-bromo- (4a), 4-methyl (4e), and 4-acetylaminofluorene (4j), were obtained by the trans-t-butylations of 3. Although we attempted to synthesize 1,8-disubstituted fluorene from 3,6-di-t-butylfluorene (2) which was derived from 2,2′-diiodo-4,4′-di-t-butyldiphenylmethane (5), by the same methods, we obtained only 2,7-disubstituted fluorene derivatives (8); it turned out electrophilic substitutions of 2 gave 2,7-disubstituted 3,6-di-t-butylfluorene derivatives.
The Independent Electrochemical Detection of H2O2 and O2 in Aqueous Alkaline Solutions on an Alkylsilanized Gold Electrode
Authors: Fujihira Masamichi , Muraki Hiroji , Aoyagui Shigeru
Published: July 2006

The cyclic voltammetric studies of H2O2 and O2 in aqueous alkaline solutions were carried out on stationary gold electrodes unmodified and modified chemically with dodecyltriethoxysilane. Although two cathodic waves were observed for both H2O2 and O2 on the unmodified electrode, only the second wave was observed for H2O2 on the modified electrode. Since the first cathodic wave of H2O2 overlaps that of O2 on the unmodified electrode, the disappearance of the first wave of H2O2 makes it possible to distinguish O2 from H2O2 on the modified electrode. The effect of alkylsilanization on the diminution and evolution of H2O2 or O2 on gold electrodes was also confirmed by employing rotating ring-disk gold electrodes unmodified and modified similarly with dodecyltriethoxysilane. Furthermore, the reduction mechanism of H2O2 and the application of the independent electrochemical detection of H2O2 and O2 are discussed.
The Crystal and Molecular Structures of 4-Ethyl-3,5-bis(phenylimino)-1,2,4-dithiazolidine and 2-Ethyl-4-phenyl-5-phenylimino-1,2,4-thiadiazolidin-3-thione
Authors: Kuriyama Mineo , Yasuoka Noritake , Kasai Nobutami , Komatsu Mitsuo , Ohshiro Yoshiki , Agawa Toshio
Published: July 2006

The molecular structures of title compounds, two of the three isomeric products in the reaction of 2-ethyl-3-phenyloxaziridine with phenyl isothiocyanate, have been determined by means of X-ray diffraction. 4-Ethyl-3,5-bis(phenylimino)-1,2,4-dithiazolidine (6b), orthorhombic, space group Pcab, a=27.171(1), b=10.213(2), c=11.421(1) Å, Z=8; 2-Ethyl-4-phenyl-5-phenylimino-1,2,4-thiadiazolidin-3-thione (8b), monoclinic, space group P21⁄n, a=9.278(1), b=27.525(3), c=5.826(1) Å, β=92.74(1)°, Z=4. Both structures were solved by the heavy atom method, and refined anisotropically by the block-diagonal least-squares procedure (R=0.066 and 0.060, respectively). The results corrected the reaction scheme proposed for the reaction of N-alkyloxaziridine with phenyl isothiacyanate.
Photochemistry of Epoxynaphthoquinones. 8. Endo-Stereoselective Photocycloaddition of 2,3-Epoxy-2,3-dihydro-2,3-dimethyl-1,4-naphthoquinone to Olefins Containing Amide Group
Authors: Maruyama Kazuhiro , Osuka Atsuhiro , Nakagawa Katsuhiko
Published: July 2006

Irradiation of a benzene solution of 2,3-epoxy-2,3-dihydro-2,3-dimethyl-1,4-naphthoquinone with olefins containing amide group, i.e., N-substituted acrylamides and N-allylcarboxamides predominantly gave the endo-cycloadducts. Upon further irradiation, the cycloadducts underwent photorearrangement to give spirophthalides and alkylidenephthalides.
Reactions of 2,4,6-Tri-t-butylphenyllithium with Deuterated Formate, Thioformate, and Selenoformate
Authors: Ishii Akihiko , Okazaki Renji , Inamoto Naoki
Published: July 2006

O-Cholesteryl chalcogenoformates-d, DC(=X)(OR) (2: X=O; 3: X=S; 4: X=Se; R=3β-cholesteryl), were synthesized and allowed to react with 2,4,6-tri-t-butylphenyllithium. 1,3,5-Tri-t-butylbenzene was a main product in each reaction. The other products were 2,4,6-tri-t-butylbenzaldehyde-d (9) for 2, 2,4,6-tri-t-butylthiobenzaldehyde-d for 3, and 9, 6,8-di-t-butyl-1-deuterio-3,4-dihydro-4,4-dimethyl-1H-2-benzoselenin, bis(2,4,6-tri-t-butyl-α-deuteriobenzyl) diselenide, and bis(2,4,6-tri-t-butyl-α-deuteriobenzyl) triselenide for 4. The mechanisms for these reactions have been discussed.
Multinuclear Solid-State NMR Study of Dehydration of Na–Y Type Zeolites
Authors: Hayashi Shigenobu , Hayamizu Kikuko , Yamamoto Osamu
Published: July 2006

High-resolution solid-state NMR spectra of 23Na, 27Al, and 29Si nuclei were measured for dehydrated Na–Y type zeolites as well as undehydrated and rehydrated samples using magic angle sample spinning technique. 1H NMR spectra, X-ray diffraction patterns, and thermal properties were measured as well. 23Na NMR results indicate that there are three types of Na sites with different symmetries in the faujasite framework; two types with high and slightly low symmetries are detected by NMR, while the third cannot because of its very low symmetry. Na ions in high-symmetry sites are moved into slightly-low and very-low-symmetry sites by the dehydration. On the other hand, the Na ions in the amorphous region are located in low and very-low-symmetry sites. 27Al and 29Si NMR lines are broadened by the dehydration, due to the distortion of AlO4 tetrahedra and the interaction with 27Al nuclei, respectively. The 29Si spin-lattice relaxation time becomes longer by the dehydration, which indicates that water molecules play some role in the relaxation.
Syntheses and Some Reactions of 4H-Cyclohepta[4,5]pyrrolo[1,2-α]pyrimidin-4-ones
Authors: Abe Noritaka
Published: July 2006

The reaction of 2-aminocyclohepta[b]pyrroles with ethyl acetoacetate in phoshoryl chloride–polyphosphoric acid gives 2-methyl-4H-cyclohepta[4,5]pyrrolo[1,2-a]pyrimidin-4-ones. A ring closure of diethyl N-(cyclohepta[b]pyrrol-2-yl)aminomethylenemalonates gives 4-oxo-4H-cyclohepta[4,5]pyrrolo[1,2-a]pyrimidine-3-carboxylates (2) in phosphoryl chloride–polyphosphoric acid or in hot t-butylbenzene, which are deesterified by the treatment with hot hydrobromic acid. Compounds 2 undergo replacement reactions towards some electrophiles at positions C-3, C-11, and C-7 (in that order).
Novel Type of the Favorskii Rearrangement Combined with Aldol Reaction Leading to γ-Butyrolactone Derivatives
Authors: Sakai Takashi , Yamawaki Akitoshi , Katayama Tsuyoshi , Okada Hiroshi , Utaka Masanori , Takeda Akira
Published: July 2006

Reaction of Aromatic aldehydes or hetero-aromatic aldehydes with 3-chloro-3-methyl-2-butanone in ethanolic KOH at room temperature gave 3,3-dimethyl-5-aryltetrahydro-2-furanone as a major product. The reaction can be tentatively explained by the combination of Favorskii rearrangement and aldol reaction.
Reaction of Aromatic Acyl Chlorides with Potassium or Sodium Cyanide Impregnated onto Amberlite XAD Resins. Efficient Synthesis of Aromatic Acyl Cyanides
Authors: Sukata Kazuaki
Published: July 2006

The effects of alkali metal cyanide impregnated on Amberlite XAD resins (KCN/XAD, NaCN/XAD) have been examined using the cyanation of benzoyl chloride. In benzene, benzoyl cyanide was obtained in a very high yield with high selectivity under mild conditions. It is proposed that the reaction occurs on the surface of the resin. On the basis of the result obtained in the absence of any solvent, the reactivity of KCN/XAD toward dimerization of benzoyl cyanide has been found to be much poorer than that of KCN in solution. Although the reaction of acyl chlorides with KCN/XAD or NaCN/XAD in benzene gave various acyl cyanides in good to excellent yields, no aliphatic acyl cyanide could be obtained.
Hydrothermal Growth of Calcite Single Crystal in NaCl Solution
Authors: Hirano Shin-ichi , Kikuta K\={o}-ichi
Published: July 2006

The hydrothermal synthesis of calcite single crystal was studied by using a NaCl solution as a mineralizer. The solubility of calcite in a 3 mol kg−1 NaCl solution was measured by a weight-loss technique to be around 2 g l−1 at 500 °C and 100 MPa. An optically clear rhombohedral crystal of up to 1.0 mm could be grown in a hydrothermal NaCl solution. The growth of a homogeneous layer of calcite could be observed on the calcite seed at 400 °C.
The Phase Transition of 1,4-Dialkyl-1,4-diazoniabicyclo[2.2.2]octane Dibromides, Cn–DABCO–Cn+1–Br2 (10≤n≤17)
Authors: Imamura Kengo , Nogami Takashi , Shirota Yasuhiko
Published: July 2006

The phase transitions of 1,4-dialkyl-1,4-diazoniabicyclo[2.2.2]octane dibromide (bis(quaternary alkyl bromide salts) of DABCO) in which the difference in the carbon numbers of the two alkyl groups is one, were studied on the basis of measurements of differential scanning calorimetry, infrared absorption spectroscopy, and bromide-anion conductivities. The DSC measurements showed that an endothermic transition occurred at Tc1 when the sample was heated from room temperature. An exothermic transition occurred at Tc2(Tc2<Tc1) when the sample was cooled after it had been heated above Tc1. The transition temperatures (Tc1 and Tc2), the transition enthalpies, and the transition entropies increased as the increase in the alkyl-chain lengths. Tc1 was found to be governed by the even numbers of the alkyl group. The temperature dependence of the IR absorption spectra showed that the trans-zigzag conformation of the alkyl chain was destroyed by a conformational change above Tc1, and that the annealed sample existed as a metastable phase. The temperature dependence of the bromide-anion conductivities showed abrupt increases in the conductivities by three orders of magnitude at around the transition temperatures. The temperatures of the conductivity jump of the virgin samples were usually higher than those of the annealed samples. The differences in these two temperatures tended to become smaller as the increase in the alkyl-chain lengths. This fact can be explained as that the solid-state properties of the unsymmetric bis(quaternary salts) of DABCO tend to resemble those of the symmetric bis(quaternary salts) of DABCO as the increase in the alkyl-chain lengths.
A Molecular Orbital Study of the Electronic Structure of Some 6-Substituted Uracils
Authors: Abdul-Ahad Paul George , Webb Graham Alan
Published: July 2006

Semiempirical molecular orbital calculations are performed on a series of 28 6-[2-(substituted phenyl)hydrazino]uracils. Approximate ground state electronic properties are obtained for each molecule studied as well as the electrostatic potentials. First and second order interaction energies are calculated for some selected point charges in the vicinity of the parent molecule. The best correlations obtained between the biological activity and the electronic and steric indicies are considered in a mechanistic context.
Spectrophotometric Determination of Palladium(II), Osmium(VIII), and Iridium(III) with 2-Methyl-1,4-naphthoquinone 4-Oxime
Authors: Shravah Kamini , Sindhwani Sharwan Kumar
Published: July 2006

2-Methyl-1,4-naphthoquinone monoxime (MNQM) forms yellow-colored 1:1 (M:L) complex with palladium(II) and brown-colored 1:2 complex with osmium(VIII) and iridium(III). The complexes are insoluble in water but soluble in 1-butanol. The reagent has been used for the spectrophotometric determination of Pd(II), Os(VIII), and Ir(III). The palladium, osmium, and iridium complexes have maximum absorption at 460, 460, and 450 nm respectively with the sensitivity of 0.012 μg Pd/cm2, 0.025 μg Os/cm2, and 0.014 μg Ir/cm2 for logIo⁄I=0.001. The optimum concentration ranges for the determination of Pd(II), Os(VIII), and Ir(III) are 1.58–10.47, 3.02–23.99, and 1.6–11.5 ppm over the pH range 6.5–7.8, 6.5–7.7, and 5.9–7.3 respectively. The determinations have also been carried out in the presence of foreign ions. MNQM reacts with palladium(II) or osmium(VIII) or iridium(III) to form yellow- or brown-colored precipitates which are extractable in 1-butanol. These systems have been studied spectrophotometrically to determine the composition and other physical constants of the complexes. The possibility of determining Pd(II) or Os(VIII) or Ir(III) in presence of diverse ions has also been investigated. Palladium(II) and osmium(VIII) have been successfully determined in synthetic solutions corresponding to the alloys.
A Structural Model for Octacalcium Phosphate–Succinate Double Salt
Authors: Mathew Mathai , Brown Walter Eric
Published: July 2006

A new structural model for octacalcium hydrogenpentakis(phosphate) succinate pentahydrate, Ca8H(PO4)5(C2H4·(COO)2)·5H2O, a reaction product of octacalcium dihydrogenhexakis(phosphate) pentahydrate, Ca8H2(PO4)6·5H2O, OCP, and succinate ions, is proposed on the basis of similarities in the unit cell dimensions and structures of OCP and calcium succinate trihydrate. This model can be used to develop information on the mode of incorporation of dicarboxylate ions into OCP and hydroxyapatite and its possible effects on biological mineralization processes.
Influence of Pressure on the Menschutkin-Type Reaction of Phenethyl Arenesulfonates with Pyridine
Authors: Yoh Soo-Dong , Park Jong-Hwan , Lee Kyung-A , Han In-Sook
Published: July 2006

Kinetic investigation of β-phenylethyl arenesulfonates with pyridine in acetonitrile revealed that the rates of these reactions which were lower than those of the reaction of benzyl benzenesulfonate with pyridine in acetone were increased with raising temperatures and pressures. The activation volumes were comparable to those of benzyl system, but activation entropies were negatively larger than those of benzyl system. From these phenomena it can be deduced that phenethyl system has more SN2 character in the transition state, comparing with the reaction of benzyl system. With raising pressures the Hammett reaction parameters (ρ) were decreased, indicating that the reaction is probably closer to tight SN2 character at higher pressures.
Bis[perfluoro(1,1-dimethylbutyl)] Trisulfide from the Cesium Fluoride-Assisted Reaction of Hexafluoropropene Dimers with Disulfur Dichloride
Authors: Suzuki Hitomi , Satake Hiroshi , Uno Hidemitsu , Shimizu Hiroaki
Published: July 2006

Perfluoro(1,1-dimethylbutanide) anion generated from hexafluoropropene dimers and cesium fluoride in N,N-dimethylformamide, reacts with disulfur dichloride to give the title trisulfide as the predominant product.
A Convenient Synthesis of Hypotensive (±)-Oudenone
Authors: Sakai Takashi , Iwata Kohji , Utaka Masanori , Takeda Akira
Published: July 2006

(±)-Oudenone, 2-(tetrahydro-5-propyl-2-furylidene)-1,3-cyclopentanedione, was conveniently synthesized by BF3-catalyzed acylation of 1,3-cyclopentanedione with 4-chloroheptanoic anhydride and subsequent cyclization with triethylamine in a 36% overall yield.
Ester Aminolysis in the Presence of Alkylammonium Carboxylate Reversed Micelles. A Mechanistic Study
Authors: El Seoud Omar A , Vieira Rita C , Novaki Luzia P
Published: July 2006

A study of ester aminolysis in the presence of dodecylammonium carboxylate reversed micelles showed that the catalytic role of the surfactant head-anion (general base) was concentration independent. The presence of cosolubilized water in the micelle did not lead to detectable ester hydrolysis.
The Use of End-Loading Technique for the Sample Preparation of Organic Powders in X-Ray Powder Diffractometry
Authors: Nakata Kazuaki , Takaki Yoshito
Published: July 2006

The end-loading technique in preparing samples for X-ray powder diffractometry is found to be an effective method for reducing preferred orientation effects of organic powder samples.
Effects of Alkyl Chain Length on Molecular Interactions. II. Complex Isomerism in the Alkyl p-Aminobenzoate-Picric Acid Systems
Authors: Togashi Atsushi , Matsunaga Yoshio
Published: July 2006

While a combination of p-aminobenzoic acid and picric acid gives a yellow-colored salt by proton transfer, the esterification of the former component compound with methyl to octadecyl groups results in the formation of not only stable salts but also metastable charge-transfer complexes.
Ylide–Metal Complexes. XII. The Preparation and Properties of Au, Be, Al, Ga, and In Complexes with Dimethylsulfoxonium Methylide
Authors: Yamamoto Yoshihisa
Published: July 2006

The reaction of dimethylsulfoxonium methylide, (CH3)2\overset+S(O)–\bar\"{C}H2 (L), with (triphenylphosphine)gold chloride, (C6H5)3PAuCl, yields a new bis(dimethylsulfoxonium methylide)gold(I) chloride, [(CH3)2S(O)CH2AuCH2S(O)(CH3)2]Cl. The reaction of the ylide L with BeCl2 yields a new compound of tetrakis(dimethylsulfoxonium methylide)beryllium dichloride, [(CH3)2S(O)CH2]4BeCl2. The reactions of the ylide L with AlCl3, GaCl3, and InCl3 yield new dimeric compounds of μ-chlorobis[tris(dimethylsulfoxonium methylide)metal] pentachloride, [{(CH3)2S(O)CH2}3M–Cl–M{CH2S(O)(CH3)2}3]Cl5 (M: Al, Ga, and In). All complexes are thermally stable.
Stereochemistry of the (Iminodiacetato or N-Methyliminodiacetato)(ethylenediamine-N-acetato)cobalt(III) Complexes
Authors: Ama Tomoharu , Niiyama Ryuichi , Kawaguchi Hiroshi , Yasui Takaji
Published: July 2006

Four geometrical isomers of [Co(mida)(edma)] were prepared in the first time and their structures were determined on the basis of their visible and UV absorption spectral data. Three of the isomers were optically resolved by the use of a column containing QAE-Sephadex of the Sb2(d-tart)22− form. Absolute configurations of the facially chelated isomers of [Co(mida)(edma)] were determined by measuring the 1H NMR spectra of the optically resolved isomers with an asymmetric carbon-containing edma (obtained from the stereospecifically deuterated (−)543CD C2-trans(O)-[Co(edma)2]2+). Absolute configuations of the facially chelated isomers of [Co(ida)(edma)] were determined on the basis of their CD spectral data.
Kinetics of Aquation of Pentaammineglycinerhodium(III) Ion in Acidic Media
Authors: Chatterjee Chinmay , Bali Aya Singh
Published: July 2006

Acid-catalyzed aquation of pentaammineglycinerhodium(III) ion has been studied kinetically in aqueous perchloric acid media (0.05–0.45 mol dm−3) over a temperature range of 60–80 °C at an ionic strength of 1.0 mol dm−3 adjusted with sodium perchlorate. Under these conditions the reaction occurs by two concurrent paths according to the rate law: Rate=ko[complex]+kH+[complex][H+], where ko and kH+ are the rate constants for the spontaneous and acid-catalyzed pathways, respectively. Analysis of rate data suggests cleavage of metal–oxygen bond in the rate determining step for both the processes.
Crystal Structures of Bis(r-1,c-3,c-5-cyclohexanetriamine)cobalt(III) Iodide and Tricyano(r-1,c-3,c-5-cyclohexanetriamine)cobalt(III) Monohydrate
Authors: Ishii Minoru , Umehara Michiko , Nakahara Masayoshi
Published: July 2006

The crystal structures of bis(r-1,c-3,c-5-cyclohexanetriamine)cobalt(III) iodide (1) and tricyano(r-1,c-3c-5-cyclohexanextriamine)cobalt(III) monohydrate (2) were determined by the X-ray diffraction technique. 1 is monoclinic with space group A2⁄a, a=10.437(2), b=16.131(2), c=12.486(2) Å, and β=94.36(3)°, and 2 is orthorhombic with space group Pbca, a=12.599(1), b=16.818(2), and c=11.659(1) Å, the final R values for 1 and 2 were 0.048 and 0.045, respectively. In both the complexes, all six-membered chelate rings formed by the r-1,c-3,c-5-cyclohexanetriamine ligand and central cobalt atom assume chair conformations. The presence of the six-membered chelate rings does not introduce, much distortion on the octahedral geometry of the chromophores. These findings are in fair agreement with spectroscopic data on these complexes.
Stereochemical Properties of Copper(II) Complexes of (S)-3-Aminohexahydroazepine. Crystal and Molecular Structure of Bromobis[(S)-3-aminohexahydroazepine]copper(II)Perchlorate [CuBr(S-ahaz)2]ClO4
Authors: Saburi Masahiko , Miyamura Kazuo , Morita Masatoshi , Mizoguchi Yasuo , Yoshikawa Sadao , Tsuboyama Sei , Sakurai Tosio , Tsuboyama Kaoru
Published: July 2006

A series of copper(II) complexes of (S)-3-aminohexahydroazepine (abbreviated as S-ahaz) were prepared. The molecular structure of bromobis[(S)-3-aminohexahydroazepine]copper(II) perchlorate, [CuBr(S-ahaz)2]ClO4, was determined using single-crystal X-ray diffraction method. The complex crystallizes is space group P212121 with a=13.449(6), b=17.411(11), c=7.937(2) Å, and Z=4. The structure was solved by the direct method and refined by the least squares to R value of 0.068 for 1853 unique reflections. The Cu2+ ion has the square-pyramidal five-coordination geometry with four nitrogen atoms as basal donors and a bromide as an apical donor. The structures of other copper(II) complexes of S-ahaz were assigned on the basis of the above X-ray analysis result, together with electronic spectral and conductivity measurements. The complexes having the formula Cu(S-ahaz)2X(ClO4) (X−=CI−, I−, NCS−, ONO−) were assigned to have square-pyramidal five-coordinated structures. The S-ahaz complexes Cu(S-ahaz)2X2 (X−=Cl−, Br−, NO3−) were also considered to have similar five-coordination geometries, while the complexes Cu(S-ahaz)2X2 (X−=ClO4−, BF4−) to be four-coordinated in the crystalline state.
Reactions of 3-(2-Methyl-1,3-dioxolan-2-yl)tropolone Methyl Ethers with Hydrazines, Thiourea, Guanidine, and Amidines
Authors: Imafuku Kimiaki , Kikuchi Yosuke , Yin Bing-Zhu
Published: July 2006

3-(2-Methyl-1,3-dioxolan-2-yl)tropolone, prepared from 3-acetyltropolone, was methylated with diazomethane to afford 2-methoxy-3-(2-methyl-1,3-dioxolan-2-yl)tropone (3a) and 2-methoxy-7-(2-methyl-1,3-dioxolan-2-yl)tropone (3b). The methyl ether 3a reacted with hydrazine to afford 2-hydrazono-3-(2-methyl-1,3-dioxolan-2-yl)-3,5-cycloheptadien-1-one and 3-methyl-1,8-dihydrocycloheptapyrazol-8-one. The reaction with methylhydrazine afforded 3-(2-methyl-1,3-dioxolan-2-yl)-2-methylhydrazono-3,5-cycloheptadien-1-one and 1,3-and 2,3-dimethyl-dihydrocycloheptapyrazol-8-ones. Another methyl ether 3b reacted with hydrazine to afford 2-hydrazino-7-(2-methyl-1,3-dioxolan-2-yl)tropone, while the reaction with methylhydrazine gave 2-(2-methyl-1,3-dioxolan-2-yl)-7-(2-methylhydrazino)tropone, 2-(2-methyl-1,3-dioxolan-2-yl)-7-(1-methylhydrazino)tropone, and 1,3-dimethyl-8-methylhydrazono-1,8-dihydrocycloheptapyrazole. On the other hand, the methyl ether 3a reacted with guanidine, acetamidine, and benzamidine to give 4-(2-methyl-1,3-dioxolan-2-yl)-2-amino-, 2-methyl-, and 2-phenylcycloheptimidazole, respectively. The reaction of the methyl ether 3b also gave the same products. The reaction of 3b with thiourea afforded 2-mercapto-4-(2-methyl-1,3-dioxolan-2-yl)cycloheptimidazole but 3a resulted in the rearrangement to ethyl 2-(2-methyl-1,3-dioxolan-2-yl)benzoate.
Racemization of Mandelic Acid at the Surface of Talc Powder
Authors: Ikekawa Akiko , Hayakawa Sohachiro
Published: July 2006

The addition of talc powder in an ethanolic solution of mandelic acid gave a large change of its optical rotation. It was confirmed by absorption spectrography, thin-layer chromatography, and gas chromatography that mandelic acid was racemized at the surface of the talc powder. The IR spectra showed that racemization took place when mandelate anions adsorved weakly at the surface of the talc. It was concluded that the H atom at the C atom in the second position of a mandelate anion was adsorbed at a basic site of the talc surface to deprotonate and also that the deprotonation was enhanced by the interaction between the carboxyl group and an acidic site.
Effect of Cationic Charge in Electrolyte-Amphoteric Ion-Exchange Membrane System
Authors: Hirata Yutaka , Date Masashi , Yamamoto Yukiko , Yamauchi Akira , Kimizuka Hideo
Published: July 2006

In order to clarify the membrane phenomena in an amphoteric membrane, four different experiments were carried out in a simple electrolyte-amphoteric membrane system. The ion transport numbers obtained from the membrane potential and electrodialysis were approximately in agreement with each other. It was indicated that the transport numbers strongly depended on the ionic valence in electrolyte solution. The membrane permeability coefficient representing the dynamic behavior of ion within membrane was evaluated in terms of membrane potential, transport number, and membrane conductance. In addition, the ionic concentrations within membrane equilibrated with outer electrolyte solution were measured to obtain the mobilities within membrane. The membrane phenomena were discussed on basis of the present experimental results.
Synthetic Inorganic Ion-Exchange Materials. XXXXVI. Ion-Exchange Behavior of Titanium(IV) Antimonate Cation Exchanger for Alkali Metal Ions in Ammonium Nitrate Media
Authors: Chitrakar Ramesh , Abe Mitsuo
Published: July 2006

Titanium(IV) antimonate (TiSbA) showed an extremely high selectivity for lithium ions in ammonium nitrate media, the increased selectivity order for microamounts being Rb+<Na+<Cs+<K+<<Li+. The selective separation of lithium ions from other alkali metal ions can be achieved on small columns of TiSbA by a mixed solution of nitric acid and ammonium nitrate.
(Acetylacetonato)(N,N,N′,N′-tetramethylethylenediamine)copper(II) Tetraphenylborate as a Solvent Basicity Indicator
Authors: Soukup Rudolf Werner , Sone Kozo
Published: July 2006

The title complex, [Cu(acac)(tmen)]BPh4, is a color indicator for solvent basicity which serves better than the corresponding perchlorate in very weak donor solvents owing to its reluctance in ion-pair formation. The complex cation [Cu(acac)(tmen)]+ decomposes in very strong donor solvents, but these indicators may still be used in them with some care.
Light-induced Electron-transfer Reactions. 5. Kinetics of the Oxidation of Ethylenediaminetetraacetatocobaltate(II) Complexes by Peroxodisulfate Ion, Induced by Irradiation with Visible Light of Aqueous Solutions Containing Tris(2,2′-bipyridine)ruthenium(II) Ion
Authors: Nishida Suzuko , Kimura Masaru
Published: July 2006

The oxidation reaction of ethylenediaminetetraacetatocobaltate(II) ([Co(edta)]2−) by peroxodisulfate ion (S2O82−) is greatly accelerated by irradiation with visible light of aqueous solutions containing tris(2,2′-bipyridine)ruthenium(II) ion ([Ru(bpy)3]2+). The overall reaction is 2[Co(edta)]2−+S2O82− →2[Co(edta)]−+2SO42−. The [Ru(bpy)3]2+ ion acts as a photosensitizer and -catalyst for this reaction, and the mechanism consists of a chain reaction being initiated by the quenching reaction of the photoexcited ruthenium(II) complex ion ([Ru(bpy)3]2+*) by S2O82− ion. The mechanism of the reaction is presented to account for the results obtained.
The Synthesis of CdTe by Means of Fused Salt Electrolysis and Its Characterization
Authors: Minoura Hideki , Kitakata Masakazu , Sugiura Takashi , Murayama Minoru , Ueno Yasusada
Published: July 2006

Crystalline cadmium telluride layers of a cubic structure have been deposited potentiostatically on graphite cathodes by means of fused salt electrolysis employing CdCl2 and TeO2/Na2TeO3 in an LiCl–KCl eutectic melt at 450 °C. X-Ray diffraction and scanning-electron-microscope studies show that (i) these layers have a tendency to grow with a preferred orientation along the 〈111〉 direction and (ii) the surface morphology changes drastically with the change in the applied potential. Voltammetric analyses indicate two distinct mechanisms for cadmium telluride deposition; one is the codeposition of cadmium and tellurium occurring at potentials more negative than −0.2 V(vs. Ag/AgCl), and the other is the ionic reaction of the cathodically formed telluride ion with the cadmium ion occurring at potentials more negative than −0.7 V(vs. Ag/AgCl). As-deposited crystals are either n- or p-type, depending on the melt composition and the applied potential.
Application of Mössbauer Spectroscopy to a Structural Study of Superionic Conducting AgI–Ag2O–B2O3 Glasses
Authors: Nishida Tetsuaki , Ogata Michiko , Takashima Yoshimasa
Published: July 2006

A structural study of silver borate glasses containing 20 mol% AgI and 1 mol% 57Fe2O3 has been performed by Mössbauer spectroscopy. A Mössbauer spectrum of these glasses consists of an asymmetric quadrupole doublet with an isomer shift smaller than 0.4 mm s−1 with respect to metallic iron. This indicates that the individual Fe3+ ions are present at the substitutional sites of the tetrahedral boron atoms constituting BO4 units as a network former. An increase in the Ag2O content results in continuous decreases in the isomer shift and the quadrupole splitting when the Ag2O content exceeds about 16 mol%, which corresponds to the Ag2O/B2O3 ratio of 0.25 and the alkali oxide content of 20 mol% in the binary borate glasses. These results are ascribed to the formation of nonbridging oxygen atoms in the tetrahedral BO4 and FeO4 units. A glass transition temperature (Tg) of the glasses shows a distinct composition dependency, having a maximum around 16 mol% Ag2O. These lead to the conclusions that planar BO3 units are changed into the tetrahedral BO4 units in the lower Ag2O content region and that the nonbridging oxygen atoms are formed in the BO4 and FeO4 units when the Ag2O content is higher than 16 mol%. These conclusions are well consistent with the composition dependency of the electric conductivity which shows a minimum when the Ag2O content is 10–15 mol%.
Peptide Synthesis in Aqueous Solution. I. Application of p-Dialkylsulfoniophenols as a Water-Soluble Coupling Reagent
Authors: Kouge Katsushige , Koizumi Tatsuya , Okai Hideo , Kato Tetsuo
Published: July 2006

(p-Hydroxyphenyl)dimethylsulfonium methyl sulfate(HODMSP·MeSO4−) was found to be an excellent coupling reagent having a water-soluble property and a high reactivity; it worked as satisfactory as usual active esters in regard to the reactivity, product purity, and racemization. The marked advantage of the HODMSP·MeSO4− active ester method was the fact that bifunctional residues such as Arg, Lys, Cys, and Tyr could be selectively acylated when the pH of the reaction mixture was controlled. The molluscan neuropeptide FMRFamide(Phe–Met–Arg–Phe–NH2) was synthesized by this new active ester method for an evaluation of this method to further applications involving peptide syntheses.
Methanol-Incorporated Photoaddition of N-Methyl-1,2-naphthalenedicarboximide with Alkenes and Dienes
Authors: Kubo Yasuo , Mihara Mariko , Araki Takeo
Published: July 2006

Irradiation of acetonitrile-methanol solutions of N-methyl-1,2-naphthalenedicarboximide (1b) with 1,1-diphenylethylene gave a methanol-incorporated adduct at a carbonyl carbon atom in 1b together with 2,2-diphenylethyl methyl ether as a typical electron-transfer photosensitized product. The photoreaction of 1b with α-methylstyrene, styrene (2c), or 2-methyl-2-butene in the same solvent system gave a regio-isomeric pair of a mixture of two diastereomers of methanol-incorporated adducts at carbonyl carbon atoms. The irradiation of 1b with 2,3-dimethyl-2-butene and ethyl vinyl ether (2h) in benzene–methanol afforded methanol-incorporated adducts, although no reaction was observed for irradiation in acetonitrile–methanol. The irradiation of 1b with 2,5-dimethyl-2,4-hexadiene in acetonitrile–methanol also resulted in the formation of methanol-incorporated adducts. The values of the free-energy change associated with an electron-transfer (ΔGet) from the alkenes to the singlet excited state of 1b and fluorescence quenching rate constants support the photochemical single-electron-transfer mechanism for the addition. A preferential addition at the carbonyl carbon atom in 1b as well as that at the more sterically hindered carbonyl carbon atom in the reaction of 1b with 2c and 2h is explainable on the basis of the spin densities of the radical anion of 1b derived by a photochemical single-electron-transfer.
Infrared Absorption Study of Peptide Fragments of Human Hemoglobin α-Chain (123–136) in the Solid State
Authors: Narita Mitsuaki , Doi Masamitsu , Takegahara Hitoshi
Published: July 2006

In order to evaluate the influence of polar amino acid residues on peptide conformations, IR absorption spectroscopic analysis of peptide fragments of human hemoglobin α-chain (123–136) and Boc–Leun–OBzl (n=3–6,9, and 12) was performed in the solid state. The polar amino acid residues involved in the peptide fragments are in the following: Asp(OBzl), Lys(Z), Ser(Bzl), and Thr(Bzl). Regardless of the amino acid composition, all of the peptides equal to or larger than a pentapeptide level exhibited a high potential for the formation of a β-sheet structure in the solid state. Conformational behaviors of peptides having polar amino acid residues are similar to those of Boc–Leun–OBzl, indicating that polar side chains can not cause disturbance of the formation of β-sheet structures. The fine relationship among the conformation, solubility, and 〈Pc〉 value of the peptide fragments strongly supports the propriety of the solubility prediction method for peptide intermediates. The influence of shear stress on peptide conformations in the solid state was also investigated precisely, and it was suggested that a heptapeptide size had the potential for the development of a helical structure in the solid state.
Synthesis of (Diethoxyphosphoryl)acetonitrile Oxide and Its Cycloaddition to Olefins. Synthetic Applications to 3,5-Disubstituted 2-Isoxazolines
Authors: Tsuge Otohiko , Kanemasa Shuji , Suga Hiroyuki , Nakagawa Norihiko
Published: July 2006

(Diethoxyphosphoryl)acetonitrile oxide undergoes regioselective cycloaddition to olefins leading to 3-[(diethoxyphosphoryl)methyl]-2-isoxazolines or -isoxazole. The phosphorus-stabilized carbanions generated by deprotonation of the cycloadducts can be utilized for the condensation with carbonyl compounds, alkylation, and oxidation with oxygen to provide 3,5-disubstituted 2-isoxazolines as useful synthetic building blocks. Raney nickel hydrogenolysis of 3-[(diethoxyphosphoryl)methyl]-2-isoxazolines gives β-hydroxy-β′-phosphoryl ketones bearing a variety of functional groups, which can be further converted into α,β-unsaturated β′-phosphoryl ketones.
Structure-Activity Relationship of a Heat-Stable Enterotoxin Produced by Yersinia enterocolitica
Authors: Yoshimura Shoko , Hidaka Yuji , Aimoto Saburo , Shimonishi Yasutsugu , Takeda Tae , Miwatani Toshio , Takeda Yoshifumi
Published: July 2006

Several shorter analogues of heat-stable enterotoxin (ST) produced by Yersinia enterocolitica were synthesized by a conventional method and their toxicities were examined by using suckling mice. The full enterotoxigenic activity of ST of Y. enterocolitica was found to be carried on a peptide, which consists of 13 amino acid residues from the 18th Cys to the C-terminal Cys and has a similar amino acid sequence to those of ST’s produced by enterotoxigenic Escherichia coli (S. Aimoto et al., Eur. J. Biochem., 129, 257 (1982)) and Vibrio cholerae non-01 (T. Takao et al., FEBS Lett., 193, 250 (1985)). The results imply that the structural elements for expression of the toxicity are present in the common amino acid sequences of ST’s of Y. enterocolitica, E. coli, and V. cholerae non-01.
The Structure of Graucin A, a New Bitter Limonoid from Evodia grauca Miq. (Rutaceae)
Authors: Nakatani Munehiro , Takao Hideki , Iwashita Takashi , Naoki Hideo , Hase Tsunao
Published: July 2006

Graucin A, a new bitter limonoid, has been isolated from the root bark of Evodia grauca Miq. as well as the known limonoids limonin, rutaevin and limonin diosphenol. Its structural and stereochemical assignments were made using NMR (COSY and NOESY), and CD spectroscopy, which indicated the uncommon 5β-H configuration of this new compound. Rutaevin was also recognized to be a 5β-H limonoid.
Electronic Structure of (BEDT–TTF)CuCl2 Complex
Authors: Tanaka Masashi , Kawamoto Atsushi , Tanaka Jiro , Sano Mitsuru , Enoki Toshiaki , Inokuchi Hiroo
Published: July 2006

The X-ray photoelectron spectra and the ESR spectra of the (BEDT–TTF)CuCl2 complex were taken. The analysis of the X-ray photoelectron spectra shows that the Cu atoms in (BEDT–TTF)CuCl2 are in a mixed-valence state consisting of mono and bivalent cations and the concentration ratio of Cu(I) and Cu(II) is determined to be 2:1. The ESR signals show the presence of the BEDT–TTF cation radical and Cu(II)Cl2. The temperature dependence of the magnetic susceptibility of these components were obtained from the ESR data.
Study of One-Dimensional Metal Complexes: K[Ni(mnt)2]·H2O and K[Pt(mnt)2]·H2O
Authors: Kutsumizu Shoichi , Kojima Norimichi , Ban Toshiro , Tsujikawa Ikuji
Published: July 2006

The crystal structure, electrical conductivity and electronic and IR absorption spectra of two metal complexes, K[Ni(mnt)2]·H2O and K[Pt(mnt)2]·H2O (mnt=1,2-dicyano-1,2-ethylenedithiolato, C4N2S22−) were investigated. These two metal complexes belong to orthorhombic system and the lattice constants are a=12.00 Å, b=28.85 Å, and c=3.90 Å for the Ni complex and a=12.11 Å, b=29.23 Å, and c=7.73 Å for the Pt complex. Despite the same stoichiometries and similar crystal structures, the conductivity of Pt complex is 103 times as high as that of the Ni complex. The difference in the conductivity between the Ni and Pt complexes may be explained from the density of the unpaired electron on the central metal. The effects of the central metal on the electrical conduction properties may not be negligible for this type of complexes.
Synthesis of 1,4-Diaminocyclitol Antibiotics. I. Synthesis of 4′-Hydroxyfortimicin D
Authors: Kanai Kazuaki , Sakamoto Itsuki , Miyamoto Yasunobu , Ogawa Seiichiro , Suami Tetsuo
Published: July 2006

The 4′-hydroxy analog of fortimicin D has been synthesized by condensation of 4-O-acetyl-2,6-bis(2,4-dinitrophenylamino)-2,3,6-trideoxy-α-d-ribo-hexopyranosyl chloride with a partially protected aminocyclitol, 1,2:4,5-di-N,O-carbonylfortamine B, followed by deprotection.