bluuebunny/crossref_metadata_2025 huggingface dataset:
Peptide Synthesis in Aqueous Solution. III. Synthesis and Biological Activity of Cyclohexylamide Derivatives of Peptides Related to a Molluscan Neuropeptide, FMRFamide (Phe–Met–Arg–Phe–NH2)
Authors: Kouge Katsushige , Katakai Yukari , Soma Haruko , Kondo Miyuki , Okai Hideo , Takemoto Mayumi , Muneoka Yojiro
Published: July 2006

In order to investigate the role of C-terminal Phe4–NH2 of FMRFamide (Phe–Met–Arg–Phe–NH2) to the biological activity, 30 kinds of cyclohexylamide derivatives of peptides related to FMRFamide were synthesized and their FMRFamide-like activity was measured. From the results, it was found that the peptide which was placed at C-terminal Phe4–NH2 by d-Ala–CHA showed only a relaxing activity. Furthermore, it was recognized that Met–Arg–Asp–diCHA inhibited FMRFamide contraction selectively.
Preparation of Bicyclo[3.3.1]nonane-2,4-dione Derivatives
Authors: Inouye Yoshinobu , Kojima Tsutomu , Owada Jun , Kakisawa Hiroshi
Published: July 2006

Bicyclo[3.3.1]nonane-2,4-dione and 7-endo-benzyloxy-9-methylenebicyclo[3.3.1]nonane-2,4-dione were prepared starting from bicyclo[3.3.1]nonan-2-one and 7-endo-benzyloxybicyclo[3.3.1]nonane-2,9-dione, respectively. The key reaction was the NCS oxidation of the 2,2-ethylenedioxy-4-phenylthiobicyclo[3.3.1]nonanes, derived from the corresponding bicyclo[3.3.1]non-3-en-2-ones.
Conformations of Some Monosubstituted N-Benzylideneanilines
Authors: Patnaik Lalit N , Das Sarojini
Published: July 2006

Theoretical computations , using quantum mechanical PCILO method, have been carried out on the conformations of four monosubstituted N-benzylideneanilines—N-benzylidene-4-nitroaniline (1a), N-benzylidene-4-dimethylaminoaniline, N-(4-nitrobenzylidene)aniline, and N-(4-dimethylaminobenzylidene)aniline. The aniline ring is found to be most twisted (60°) in 1a, while in all other cases , the twist angle is 30°. The results have been compared with earlier experimental findings and rationalized in terms of two factors contributing to nonplanarity , namely , the overlapping of bridge nitrogen lone pair with the π-system of the aniline ring and a steric interaction between the azomethine hydrogen and one of the ortho hydrogens in the aniline ring.
Photochemical Reactions of the Natural Furocoumarin, Imperatorin
Authors: Abou-Elzahab M M , Metwally M A , Dawidar A M , Abdel-Mogib M , Abu-Mustafa E A
Published: July 2006

Photochemical behavior of imperatorin was investigated including photolysis and sigmatropic effects in different solvents and photodimerization. The structures of the photoproducts obtained were determined by chemical and spectral methods.
Protection of Functional Groups and Stannylation of Phenylalanine
Authors: Metwally S A , Coenen H H , Stöcklin G
Published: July 2006

The protection of both amino and carboxylic acid groups in p-halogenated phenylalanine was done by using different reagents. The protected amino acid was stannylated by using hexamethyldistannane in the presence of tetrakis(triphenylphosphine)palladium as catalyst.
Adsorption of Uranium from Nitric Acid Solutions Using Crystalline Hydrous Titanium Dioxide Fibers
Authors: Komatsu Y\={u} , Fujiki Yoshinori , Sasaki Takayoshi
Published: July 2006

The adsorption of uranium on an ion exchanger of crystalline hydrous titanium dioxide fibers from nitric acid solutions has been studied. The rate of the adsorption of uranium was much higher than that of alkaline earth metal ions. The adsorption behavior of uranium was well explained by their ion exchange with hydrogen ions in the fibers.
The Magnetic Properties of the Copper(II) (Disubstituted Acetate) Adducts with Ammonium Chloride
Authors: Emori Shuji , Tohyama Yayoi , Muto Yoneichiro
Published: July 2006

Various copper(II) (disubstituted acetate) adducts with ammonium chloride have been prepared and characterized by magnetic susceptibility and IR spectroscopy measurements. Factors affecting the magnetic moments of the dinuclear copper(II) alkanoates are discussed.
Hydrates of Organic Compounds. XIV. The Formation of Clathrate-Like Hydrates of Tetrabutylammonium Amino Carboxylates
Authors: Nakayama Haruo , Usui Hideyuki , Matsui Hiroshi
Published: July 2006

The solid–liquid phase diagrams of binary mixtures of water with a series of tetrabutylammonium α-amino carboxylates, (n-C4H9)4NOOCCH(NH2)R (R=H, CH3, C2H5, n-C3H7, and (CH3)2CH), were examined. It. It was found that all the salts examined could form hydrates with hydration numbers either around 30 or around 39.
An Unusual Cyclization of Trifluoroacetohydroximoyl and -hydrazonoyl Bromides with Malononitrile
Authors: Tanaka Kiyoshi , Suzuki Takashi , Maeno Seiji , Mitsuhashi Keiryo
Published: July 2006

Trifluoroacetohydroximoyl bromide etherate (1) reacted with an excess of malononitrile in the presence of sodium methoxide, giving a fused isoxazolopyridine 3, participated by two molecules of malononitrile, along with the conventional isoxazole 2. Similar concomitant formation of 7 and the fused pyrazolopyridines 8 was also recognized from the hydrazonoyl bromides 6 and their product ratio was found to depend on the reaction conditions, particularly on the concentration of malononitrile used.
Nitriles in Heterocyclic Synthesis. Novel Synthesis of Pyridazine Derivatives
Authors: Ibrahim Nadia Sobhy , Abdel-Galil Fathy Mohamed , Abdel-Motaleb Ramadan Maawad , Elnagdi Mohamed Hilmy
Published: July 2006

The crotononitriles 1a–c coupled with arenediazonium salts to yield either the acyclic mono- or dihydrazones depending on coupling reaction conditions. Both mono- and dihydrazones could be cyclized to the corresponding pyridazine derivatives. Direct formation of pyridazines on coupling 1b and 1c with arenediazonium salts was observed. Structures of reaction products are confirmed by spectral and analytical data.
Liquid-Phase Hydration of Acrylonitrile to Acrylamide over the Manganese Dioxide Catalyst
Authors: Sugiyama Kazuo , Miura Hiroshi , Nakano Yasushi , Suzuki Hidehiro , Matsuda Tsuneo
Published: July 2006

The liquid-phase hydration of acrylonitrile to acrylamide was examined over a manganese dioxide catalyst at 65 °C. When the catalysts were treated at 110–500 °C, both the acidity and the reaction activity of the catalysts decreased at temperatures above 110 °C. The reduction of the solid acidity of heat-treated samples decreased the catalytic activity of the catalysts. It was confirmed that the solid acidity of manganese dioxide was derived from acidic hydroxyl groups on the catalyst surface through their dispersion in water. A good relationship between the number of surface hydroxyl groups and the catalytic activity of the manganese dioxide was observed; its hydration ability was depressed by the addition of an aqueous base as a NaOH solution. These results show that the acidic surface hydroxyl group of a manganese dioxide catalyst is the active site of acrylonitrile hydration. The kinetic behavior of both acrylonitrile and water was examined and the reaction rate snowed both first and zero orders with respect to the acrylonitrile and water concentration, respectively. The hydration mechanism of acrylonitrile on the manganese dioxide catalyst is discussed.
Cationic Motions and Phase Transitions in [(CH3)4N]GaBr4 Crystals as Studied by 1H NMR and Differential Thermal Analysis Techniques
Authors: Sato Setsuko , Nakamura Daiyu
Published: July 2006

Two phase transitions were located for solid [(CH3)4N]GaBr4 at 404 and 138 K. The temperature dependences of 1H NMR spin-lattice relaxation times were determined mainly at 20 MHz. A shallow 1H T1 minimum appearing at ca. 400 K and a deep one below ca. 250 K were observed. The latter minimum could be explained by the occurrence of the overall reorientation of the cation as a whole with an activation energy of 14.5 kJ mol−1. The shallow 1H T1 minimum may come from temperature dependent quadrupolar relaxation of bromine nuclei through the dipolar relaxation of the second kind.
The Polarographic Reduction of Acids in Pyridine, The Cause of the Differences in Half-Wave Potentials with Various Supporting Electrolytes
Authors: Hojo Masashi , Akita Yoshihiro , Nishikawa Kazukiyo , Imai Yoshihiko
Published: July 2006

The polarographic reductions of acetic, benzoic, p-toluenesulfonic, and perchloric acids have been examined in pyridine solutions with tetrabutylammonium, tetraethylammonium, sodium, and lithium perchlorate as the supporting electrolytes. The difference in the half-wave potentials of the acids was explained in terms of the difference in the degree of interaction between the pyridinium ion and the conjugate bases (e.g., CH3COO−) made of the acids. The alkali-metal ions interact with the acetate or benzoate ion to form RCOO−(M+)2 (M=Li and Na). The formation constants of RCOO−(M+)2 were evaluated by means of the positive shift in the half-wave potential of the pyridinium ion in the presence of a large excess of the alkali metal ions. Substituted acetic and benzoic acids and phenols were also examined so as to ascertain the effect of the substituent groups.
Synthesis, Characterization, and Optical Resolution of Electrically Neutral Octahedral Cobalt(III) Complexes Containing the Tetradentate Ligand
Authors: Nakazawa Hiroshi , Ohtsuru Hisaka , Yoneda Hayami
Published: July 2006

Three geometrical isomers of [Co(edda)(aa)] where edda=N′,N-ethylenediaminediacetato, aa=glycinato (gly), β-alaninato (β-ala), have been synthesized and characterized. They have been completely resolved into the enantiomers, except unsym-cis-fac-[Co(edda)(β-ala)], by the bis(μ-d-tartrato)diantimonate(III) anion, [Sb2(d-tart)2]2−, form of QAE-Sephadex resin with water as the eluent, and their absolute configurations have been determined based upon the circular dichroism spectra. It has been revealed that the Δ enantiomer is favored more by [Sb2(d-tart)2]2− than the Λ enantiomer irrespective of the kind of the geometrical isomers. Consideration on the mechanism of the optical resolution has been presented.
Nocovalent Interactions in Metal Complexes. 14. Proton NMR Spectroscopic Investigation on Stereoselectivity in Cobalt(III) Complexes of Various 3-Substituted 1-Phenyl-1,3-)propanediones
Authors: Nakamura Michio , Okawa Hisashi , Ito Tasuku , Kato Masako , Kida Sigeo
Published: July 2006

1:3-Cobalt(III) complexes of 3-substituted 1-phenyl-1,3-propanediones (C6H5–CO–CH2–CO–R) have been synthesized, and their stereoselectivities were studied with 400 MHz proton NMR spectroscopy. When the substituent (R) was ethyl, propyl, isopropyl, butyl, or isobutyl, the complexes were obtained in a mixture of fac and mer isomers with the fac/mer ratio of 1/3, demonstrating statistical distribution. When the substituent was t-butoxymethyl or cyclohexyloxymethyl the fac isomer was predominantly formed. The stereoselectivity in the geometrical isomer formation of the complexes was ascribed to the interligand CH/π-interaction occuring between the R group and the phenyl ring. The stereoselectivities of the complexes [Co(l-moba-X)3] (l-moba-X−=4-(l-menthyloxy)-1-(p-X-phenyl)-1,3-butanedionate ion; X=H, Br, CH3) were also examined by means of 1H NMR spectroscopy and compared with the CD spectral result previously reported.
Atmospheric Concentrations of Halocarbons in Japan in 1979–1986
Authors: Makide Yoshihiro , Yokohata Akihito , Kubo Yuji , Tominaga Takeshi
Published: July 2006

The average atmospheric concentrations of halocarbons in the mid-latitude Northern Hemisphere have been measured accurately for 7 years from 1979 to 1986. Atmospheric samples were collected in summer and winter in Hokkaido (40–45°N), and the halocarbons at 10–400 pptv (pptv=10−12 v/v) concentrations were determined with 0.5% precision. The concentrations of halocarbons with long lifetimes have been increasing steadily (CCl2F2: 18 pptv/year, CCl3F: 8–9 pptv/year, CH3CCl3: 4 pptv/year, CCl4: 2 pptv/year); those of shortlived halocarbons (CHCl=CCl2 and CCl2=CCl2) are low (<25 pptv) and show only seasonal variations.
Synthesis, Characterization, and Isomerization of trans- and cis-[CoCl2(1,2- or 1,3-diphosphine)2]+ and Related Complexes
Authors: Ohishi Tomoji , Kashiwabara Kazuo , Fujita Junnosuke
Published: July 2006

A number of new diphosphine complexes of cobalt(III), trans- and cis-[CoCl2(dmpe, dmpp, dbpe, or dpee)2]+, trans- and cis-[CoBr2(dmpe)2]+, trans- and cis-[CoCl(H2O)(dmpe)2]2+, trans-[Co(I2 or BrI)(dmpe)2]+, and [Co(CO3)(dmpp or dbpe)]+ have been prepared and characterized, where dmpe, dmpp, dbpe, and dpee denote 1,2-bis(dimethylphosphino)ethane, 1,3-bis(dimethylphosphino)propane, 1,2-bis(dibutylphosphino)ethane, and cis-1,2-bis(diphenylphosphino)ethylene, respectively. The trans isomers of the dihalogeno complexes are stable to aquation, while the cis isomers release one of the halide ions in water fairly rapidly to yield cis-[CoX(H2O)(diphosphine)2]+ which isomerizes to the trans isomer on exposure of ultraviolet light. The cis-[CoCl2(diphosphine)2]+ complexes in methanol or ethanol solution isomerize to the trans isomer, and the rates were followed spectrophotometrically in the temperature range of 39.0–65.0 °C. The rates have a first-order dependence on the complex concentration. Both the ΔH\eweq and ΔS\eweq values for the isomerization increase in the order diphosphine=dmpe<dmpp<dbpe<dpee. This order coincides with the increasing order in cone angle of phosphine ligands, and suggests that the difference in rates among the complexes comes from a steric factor. Absorption spectra of all the complexes have been recorded and the results compared with those of the corresponding ethylenediamine complexes.
A High Resolution 23Na NMR Study of Sodium Complexes with Ionophores in Solution. Stability of Complexes as Viewed from Displacements of 23Na Chemical Shifts as Referred to Those in the Solid State
Authors: Saitô Hazime , Tabeta Ryoko
Published: July 2006

We have recorded 23Na NMR spectra of sodium complexes with naturally occurring and synthetic ionophores in chloroform and methanol solution, to gain insight into conformational stability of these complexes as examined from the displacements of 23Na chemical shifts with respect to those in the solid state. Interestingly, the 23Na chemical shifts of sodium complexes with monensin and tetranactin obtained in chloroform solution are very close to those in the solid, as a result of adopting similar conformation between the solid and solution. For the rest of complexes, however, the 23Na NMR signals are displaced downfield in solution as compared with those of the solid state. Such downfield shifts are well interpreted in terms of the presence of conformational fluctuation and/or sodium ions interacting with solvent or anions. Therefore, downfield displacement is more significant in methanol which can be good ligand molecules. The presence of fluctuation-induced quadrupole coupling constants is consistent with our view about 23Na chemical shifts. These quadrupole interactions were reduced in methanol solution, owing to the presence of exchange with solvents.
Glycosylation of 4,7,8,9-Tetra-O-acetyl-2-deoxy-2β,3β-epoxy-N-acetylneuraminic Acid Methyl Ester
Authors: Okamoto Kaoru , Kondo Tadao , Goto Toshio
Published: July 2006

Reaction of the 2β,3β-epoxyneuraminic acid derivative prepared from 2,3-dehydroneuraminic acid derivative with primary or secondary alcohol gave the corresponding glycoside(s) or ortho ester.
Optical Resolution by Preferential Crystallization of 1,1,3,3-Tetramethylbutylammonium Salt of N-Formyl-Dl-α-phenylglycine
Authors: Shiraiwa Tadashi , Miyazaki Hideya , Imai Tomoki , Sunami Michio , Kurokawa Hidemoto
Published: July 2006

Infrared spectrum, solubility, and ternary phase diagram of solubility indicated that 1,1,3,3-tetramethylbutylammonium salt (Dl-TMB salt) of N-formyl-Dl-α-phenylglycine is a conglomerate. In order to resolve Dl-TMB salt efficiently, crystallization of d- and l-TMB salts was examined by free energy of critical nucleation in supersaturated solutions. Successive preferential crystallization of Dl-TMB salt was experimented at 10 °C for racemic solution in ethanol with the degree of supersaturation of 130%, and d- and l-α-phenylglycine with 100% optical purity were obtained from pure d- and l-TMB salts.
A Highly Stereoselective Synthesis of (E)-Enol Lactones by the Wittig Reaction of Cyclic Anhydrides with (α-Alkoxycarbonylethylidene)triphenylphosphorane
Authors: Tsuboi Sadao , Fukumoto Hirohumi , Wada Hiroshi , Takeda Akira , Fukuyama Keiichi
Published: July 2006

Reactions of glutaric anhydride and methyl- or phenyl-substituted ones with (α-alkoxycarbonylethylidene)triphenylphosphorane (2a, ethoxy; 2b, t-butoxy) gave the corresponding 6-alkoxycarbonyl-5-hepten-5-olides (3) and 6-alkoxycarbonyl-4-hepten-5-olides in good yields. The reaction proceeded highly stereoselectively to give (E)-3. The stereochemistry of 3 was determined by an X-ray crystallographic analysis. The reaction of adipic anhydride with 2a afforded 7-ethoxycarbonyl-5-octen-6-olide, 7-ethoxycarbonyl-5,6-octadienoic acid, and (4E, 6E)-7-ethoxycarbonyl-4,6-octadienoic acid. A treatment of nonanedioic anhydride with 2a gave 10-ethoxycarbonyl-8,9-undecadienoic acid, (7E,9E)-10-ethoxycarbonyl-7,9-undecadienoic acid, and diethyl 2-methyl-2,4-undecadienedioate in low yields.
Syntheses of 2′,3′-Dideoxykanamycin A, 2′,3′-Dideoxyamikacin and Related Substances
Authors: Kobayashi Yoshihiko , Tsuchiya Tsutomu , Umezawa Sumio , Yoneta Toshio , Fukatsu Shunzo , Umezawa Hamao
Published: July 2006

2′,3′-Dideoxykanamycin A has been prepared via two ways. 2″-O-Acetyl-4″,6″-O-benzylidene-6′-N,4′-O-carbonyl-1,3,3″-tri-N-tosylkanamycin A was converted to a 2′,3′-unsaturated compound by a modified Tipson and Cohen method. Hydrogenation followed by deblocking gave 2′,3′-dideoxykanamycin A (12). Another route for 12 was through 2′,3′-anhydro-4′,2″,4″,6″-tetra-O-benzoyl-2′-epi-1,3,6′,3″-tetrakis(N-ethoxycarbonyl)kanamycin A (16). Epoxide-ring opening of 16 with hydrogen iodide gave the 3′,2′-iodohydrin, which, after 2′-O-mesylation, led to the 2′,3′-unsaturated compound (19). Deblocking and hydrogenation of 19 gave 12. 2′,3′-Dideoxykanamycin A thus synthesized was led to 2′,3′-dideoxyamikacin and other related compounds by amino protection of 12 other than the 1-amino group by zinc acetate–ethyl trifluoroacetate method followed by 1-N-acyl or 1-urethane formation with appropriate reagents. Their antibacterial activities were described.
Synthesis of Imido-Substituted 3,8-Diphenyl-1,2-diazacycloocta-2,4,6,8-tetraenes and Their Thermolysis
Authors: Yogi Seiichi , Hokama Kozo , Takayoshi Sadamori , Tsuge Otohiko
Published: July 2006

Nucleophilic substitution of 4,7-dichloro-3,8-diphenyl-1,2-diazocine with succinimide, phthalimide, N-methyl-p-toluenesulfonamide, and o-benzosulfimide, in the presence of silver oxide, gave the corresponding 4-mono(imido)- and 4,7-di(imido)-1,2-diazocines. 4-Acetoxy-7-phthalimido- and 4-phenylthio-7-phthalimido-1,2-diazocine were also prepared. Thermolysis of the mono(imido)-1,2-diazocines in xylene under reflux afforded the corresponding di(imido)-1,2-diazocine and/or five pyridine derivatives, whose relative yields depended upon the nature of imido substitutents in the diazocines. However, 4,7-di(imido)-1,2-diazocines did not decompose in xylene under reflux. Thermolysis of 4,7-bis(phthalimido)-1,2-diazocine at 300–310 °C gave 3,6-bis(phthalimido)-2-phenylpyridine with the extrusion of benzonitrile. In the thermolysis of the acetoxy(230–240 °C) or phenylthio-substituted 1,2-diazocine (240–260 °C), 6-acetoxy- and 6-benzoyl-3-phthalimido-2-phenylpyridine, or 6(and 3)-phenylthio-3(and 6)-phthalimido-2-phenylpyridines were isolated together with benzonitrile, respectively. The feature of thermolysis was also discussed.
In Situ Generation and Synthetic Application of 2-Phenylbenzimidazoline to the Selective Reduction of Carbon–Carbon Double Bonds of Electron-Deficient Olefins
Authors: Chikashita Hidenori , Nishida Shuichi , Miyazaki Makoto , Morita Yasuhiro , Itoh Kazuyoshi
Published: July 2006

2-Phenylbenzimidazoline (PBI) as a mild, selective, and convenient reducing agent was efficiently generated in situ from o-phenylenediamine and benzaldehyde in alcohols. A generally applicable method for the selective reduction of carbon–carbon double bonds of a variety of electron-deficient olefins with an alcoholic solution of PBI is described. The reduction of α,β-unsaturated ketones to the corresponding saturated ketones could also be accomplished (but, less effectively) with PBI with the aid of a Lewis-acid catalyst. 1-Methyl-2-(o-nitrophenyl)benzimidazoline prepared and isolated by the reaction of o-nitrobenzaldehyde with N-methyl-o-phenylenediamine reduced benzylidenemalononitrile to give benzylmalononitrile and 1-methyl-2-(o-nitrophenyl)benzimidazole in high yields. This shows the validity of PBI to be the actual reducing species in the present reduction system. From a mechanistic study, the present reductions could be interpreted in terms of a mechanism involving a synchronous transport of a pair of hydrogens or a sequential transfer of a hydride and a proton from PBI to the olefins.
On a Solid-State ECD, WO3/Solid Electrolyte/Metal
Authors: Kuwabara Katsumi , Ichikawa Shoichi , Sugiyama Kohzo
Published: July 2006

Electrochromic display (ECD) was investigated using WO3 as the electrochromic material and metals as the counter electrode. WO3 was vacuum-evaporated on a glass substrate coated with indium tin oxide. A film of solid electrolyte, Sn(HPO4)2·H2O, was prepared by means of the spray method on the thin film of WO3. ECDs with metal electrodes were examined from the points of view of the change in optical density, the current-wave forms, and the response speeds in coloring and bleaching processes. ECD cells with noble metals indicated comparatively high optical density changes on coloration at a constant-voltage operation. The cell with Ag showed a high coloration speed compared with the cells containing graphite and other metals.
Synthesis of Sulfoxide-Modified Cellulose Derivatives Designed for the Permselective Membrane of Sulfur Dioxide
Authors: Imai Kiyokazu , Tezuka Yasuyuki , Shiomi Tomoo , Takada Matsunori
Published: July 2006

The Michael type addition reaction of cellulose with a series of vinyl sulfoxides, namely methyl vinyl sulfoxide, ethyl vinyl sulfoxide, t-butyl vinyl sulfoxide, and phenyl vinyl sulfoxide, was performed with NaOH as a catalyst to produce 2-(alkyl- or arylsulfinyl)ethyl cellulose derivatives. The high permselectivity of sulfur dioxide against nitrogen and oxygen was achieved through these sulfoxide modified cellulose membranes.
Self Regulation in the Cooperative Binding of Small Molecules to Linear Polymers
Authors: Sano Takayuki , Nakatsuka Thoru , Tsuruta Hirotsugu , Harada Shoji
Published: July 2006

As for the cooperative binding of small molecules to the linear polymers, including not only synthetic polymers but also biopolymers, an interesting relationship, the so called “self regulation effect” between the isolated binding constant (intrinsic binding constant) and the cooperative binding constant, (binding constant of growth process) can be observed amongst the large amount of data so far reported. The biological significances as well as the possible origin for this “self regulation mechanism” will be discussed.
Potentiometric Study of Heteropolyanion Formation from Telluric Acid and Molybdate Anion in 1M Na(Cl)
Authors: Yagasaki Atsushi , Sasaki Yukiyoshi
Published: July 2006

The equilibria in the H+–MoO42−–Te(OH)6 system in aqueous solutions were studied potentiometrically at 25.0 °C. The data were expained by (6,6,1), (7,6,1), and (8,6,1) with formation constants logβ6,6,1=50.40±0.02,logβ7,6,1=53.68±0.07andlogβ8,6,1=55.47±0.07.
Synthesis of (1-Halo-1-alkenyl)trimethylsilanes via gem-Trimethylsilylation of Vinyl Halides
Authors: Shimizu Nobujiro , Shibata Fumihiro , Tsuno Yuho
Published: July 2006

Various vinyl halides including enol silyl ethers of α-halo ketones and esters give the corresponding (1-halo-1-alkenyl)trimethylsilanes in fair to good yields on treatment with lithium diisopropylamide at Dry Ice temperature in the presence of chlorotrimethylsilane.
Electrochemical Studies of Poly(mercaptohydroquinone) and Poly(mercapto-p-benzoquinone) Films Prepared by Electropolymerization. I. Preparation of pH Microsensor and Its Fundamental Characteristics
Authors: Arai Gorou , Koike Takashi , Yasumori Iwao
Published: July 2006

Carbon fibers were electrochemically modified with poly(mercaptohydroquinones). These modified carbon fiber electrodes showed excellent Nernstian response to pH from ca. 2 to 10 and could respond within 2s in the pH range from 3 to 8. These electrodes could work well one month after kept stored in a weak acidic buffer solution and could be easily restored by electroreduction even after their functions had been lowered by successive pH measurements.
Reactions of α,β-Unsaturated Carboxylates, Malonates and Phenylacetates with Manganese(III) Acetate in the Presence of Chloride Ions
Authors: Yonemura Hiroshi , Nishino Hiroshi , Kurosawa Kazu
Published: July 2006

The reaction of alkyl (E)-3-phenylpropenoates with manganese(III) acetate in the presence of Cl− ions gave alkyl (Z)-2-chloro-3-phenylpropenoates and alkyl 2,3-dichloro-3-phenylpropanoates. Ethyl (E)-2,3-diphenylpropenoate yielded ethyl 2,3-dichloro-2,3-diphenylpropanoate. Alkyl 3,3-diphenylpropenoates gave mainly alkyl 2-chloro-3,3-diphenyl-propenoates. Ethyl 1-cyclohexenecarboxylate gave ethyl 1,2-dichlorocyclohexanecarboxylate. Dimethyl malonate yielded dimethyl dichloromalonate and tetramethyl 1,2-dichloro-1,1,2,2-ethanetetracarboxylate. Substituted malonates resulted in α-chloro derivatives. Methyl phenylacetates gave α-acetoxy derivatives.
Reaction of Dimethyl 1-Hydroxyalkylphosphonates with Some Chlorides
Authors: Yamashita Mitsuji , Morizane Takashi , Fujita Keiji , Nakatani Kaname , Inokawa Saburo
Published: July 2006

The reactions of dimethyl 1-hydroxycycloalkylphosphonates having a five- to seven-membered ring with sulfuryl chloride and phosphorus pentachloride afforded olefinic and/or dichloro derivatives of phosphonates. The mechanism of the formation of new dichloro derivatives and the reactions of dimethyl 1-methylethylphosphonate with sulfuryl chloride and phosphorus pentachloride were also investigated.
Deacylation Effect in the Hydrolysis of p-Nitrophenyl Esters by Bifunctional Comicelles Containing Imidazolyl and Hydroxyl Groups
Authors: Ihara Yasuji , Nango Mamoru , Koga Joichi
Published: July 2006

The rate constants for hydrolysis of p-nitrophenyl acetate, hexanoate, and dodecanoate catalyzed by bifunctional catalysts containing the imidazolyl and hydroxyl groups have been determined in the presence of hexadecyltrimethylammonium bromide micelles at 25 °C. The kinetic analysis suggests a nucleophilic mechanism which involves acylation followed by deacylation at the imidazolyl group. Although no appreciable differences in cooperative catalytic efficiencies are observed between the bifunctional groups in the acylation step, it is found that the deacylation rates are accelerated by the hydroxyl group of the catalyst in the presence of micelles.
Optical Resolution of (±)-Phenylsuccinic Acid by Using (−)-Proline as Resolving Agent
Authors: Shiraiwa Tadashi , Sado Yujin , Fujii Shigeru , Nakamura Mitsuhiro , Kurokawa Hidemoto
Published: July 2006

A solution of equimolar mixture of (±)-phenylsuccinic acid ((±)-PSA) and (−)-proline ((−)-Pro) in ethanol or its suspension in 2-propanol selectively gave a salt composed of 1-molar amount of PSA and 2-molar amount of (−)-Pro. The salt purified gave (+)-PSA with an optical purity of about 100%. A salt composed of equimolar amounts of PSA and (−)-Pro was obtained from the ethanolic mother liquor, and gave (−)-PSA with an optical purity of 98%.
A Michael Addition-Induced Favorskii Rearrangement
Authors: Tsuboi Sadao , Nagae Hiroyuki , Yamato Hirofumi , Takeda Akira
Published: July 2006

Reaction of 6-chloro-2-vinylidenecyclohexanone with sodium methoxide gave methyl 2-vinylidene-1-cyclopentanecarboxylate and methyl trans-2-(1-methoxyalkyl)-1-cyclopentanecarboxylate along with 6-methoxy-2-vinylidenecyclohexanone via a Michael addition-induced Favorskii rearrangement.
Effects of Surfactants and Surface Treatment on Aqueous Dispersion of Silicon Carbide
Authors: Meguro Kenjiro , Ushida Takahisa , Hiraoka Tetsuya , Esumi Kunio
Published: July 2006

The effects of the addition of surfactants and of the surface treatment upon the aqueous dispersion of silicon carbide were examined. In the case of β-SiC, the addition of nonionic surfactants having relatively longer lengths of hydrocarbon and oxyethylene chain to the β-SiC treated with a silane coupling agent enhanced the dispersion stability. On the other hand, the lack of a difference for the dispersion stability was observed between a silane coupling treated α-SiC and an untreated one by the addition of surfactants. These differences in the surface property of two kinds of SiC were confirmed by measuring the zeta potential and the heat of immersion in water.
Band Shape of Photoelectron Spectrum and Potential Energy Curve for Alkylamine
Authors: Takahashi Masao , Watanabe Iwao , Ikeda Shigero
Published: July 2006

Accurate measurements of UPS and ab initio potential energy calculations have been carried out for ammonia and several alkylamines to interpret the band shape of the UPS. Theoretical photoelectron band shape was obtained by a simple Franck–Condon approach. The calculation predicted very well the alkyl substitution effects on the ionization potentials and on the band widths of the first bands in UPS for the alkylamines. The following conclusions were obtained by comparing these theoretical photoelectron bands with experimental ones. The threshold ionization potential observed in the UPS is not always thermodynamically adiabatic ionization energy, but it can be subject to hot bands. Adiabatic ionization potential IPa of ammonia is concluded to be 10.08 eV. And the values of IPa for a series of alkylamines are evaluated by taking account of molecular vibrational frequency for the neutral state.
Use of Monoclonal Antibodies in the Study of the Conformation and Conformational Alterations in Proteins
Authors: Katchalski-Katzir Ephraim , Kenett Dan
Published: July 2006

The conformational flexibility of many of the native proteins facilitates their attainment of new reversible three-dimensional structures under well-specified conditions. Such structures appear to be of great importance in biological processes involving biologically active proteins, such as enzymes, receptors or protein hormones. Recently it was shown that the above conformational alterations can be followed not only by physicochemical methods but also immunochemically by the use of monoclonal antibodies (mAbs). mAbs are specific proteins, each capable of recognizing a corresponding well-characterized region (epitope) on the surface of a protein antigen. They are thus useful as tools in the study of the structure and properties of protein surfaces. Of particular interest is the fact that it is possible to prepare mAbs with predetermined specificities towards the different epitopes of a given protein. Such mAbs can thus be used to detect conformational alterations occurring at the different segments of a protein antigen. In the present review article we describe our own work and that of others on the use of mAbs as probes to detect the conformation and conformational alterations occurring in proteins exposed to different conditions, such as heat, adsorption onto solid surfaces, interaction with ligands and protein–protein interaction. The use of mAbs in the detection of protein folding intermediates is also described.
Design of Novel Mesomorphic Compounds: N,N′,N″-Trialkyl-1,3,5-benzenetricarboxamides
Authors: Matsunaga Yoshio , Miyajima Nobuhiko , Nakayasu Yuichi , Sakai Satoshi , Yonenaga Michihiro
Published: July 2006

N,N′-Dialkyl-1,4-benzenedicarboxamides melt with anomalously small enthalpy changes. The 1,3-analogs behave similarly but at lower temperatures. These observations provide a clue to design novel mesomorphic compounds; N,N′,N″-trialkyl-1,3,5-benzenetricarboxamides. The compounds carrying pentyl to octadecyl groups melt at temperatures between 49 and 119 °C depending upon the alkyl chain length. The clearing points are located above 200 °C. The unoriented liquid crystals show X-ray diffraction patterns consisting of two major peaks. The inner sharp peak gives a spacing, which increases as the series is ascended, from 1.40 to 2.26 nm. The outer one is sharp in the pentyl and hexyl derivatives but diffuse in the higher homologous members. The second moments of the broad-line proton NMR spectra measured above the melting points are as small as a few hundredths G2 and firmly establish the liquid-like characteristics of the alkyl chains.
A Twin-TCNQ-Type Acceptor. Synthesis of 11,11,12,12,13,13,14,14-Octacyano-1,4:5,8-anthradiquinotetramethane and Structures of the Tetraethylammonium Salts of Its Mono- and Dianion
Authors: Mitsuhashi Tsutomu , Goto Midori , Honda Kazumasa , Maruyama Yusei , Inabe Tamotsu , Sugawara Tadashi , Watanabe Tokuko
Published: July 2006

The title compound (OCNAQ) was synthesized. Treatment of 1,2,3,4,5,6,7,8-octahydroanthracene with N-bromosuccinimide (NBS) under irradiation using a 100-W light bulb in refluxing CCl4 followed by dicyanomethylation with excess of NaCH(CN)2 in Me2SO gave an isomeric mixture of 1,4,5,8-tetrakis(dicyanomethyl) derivatives. The mixture was subjected by repetition of the successive bromination-dehydrobromination procedure giving OCNAQ in 20% overall yield. The cyclic voltammogram of OCNAQ exhibits four redox waves (E1⁄21 0.26, E1⁄22 0.05, E1⁄23 −0.44, and E1⁄24 −0.53 V vs. SCE in MeCN), indicating that OCNAQ is a stronger acceptor than tetracyanoquinodimethane (TCNQ, E1⁄21 0.17 V vs. SCE). Both 1:1 and 2:1 salts, (Et4N)(OCNAQ) and (Et4N)2(OCNAQ), were obtained from reactions of Et4NI with potassium and lithium salts of OCNAQ, respectively. The X-ray crystal analyses of these salts indicate that the TCNQ moieties are boat-shaped bent to opposite directions. With the 1:1 salt, which behaves as a semiconductor (4×10−4Ω−1 cm−1 at room temperature, Ea 0.22 eV), the OCNAQ molecules are arrayed in the segregated stacking mode, while the 2:1 salt (10−4Ω−1 cm−1) has no columnar structure of the OCNAQ molecules.
Convenient Synthesis of N-Protected Amino Acid Amides
Authors: Nozaki Sukekatsu , Muramatsu Ichiro
Published: July 2006

Boc- or Z-amino acids were conveniently amidated at room temperature by a one-pot procedure employing ammonium hydrogencarbonate and N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline in yields of 81–96%. The benzyl ester-type protector for the side chains of aspartic acid and glutamic acid was not affected by the procedure.
A Convenient Synthesis of Spironorcamphors
Authors: Hori Kimihiko , Takaishi Naotake , Inamoto Yoshiaki
Published: July 2006

The effects of the base, molar ratio of the reagent, solvent and reaction temperature on the cycloalkylation of norcamphor with 1,4-dibromobutane were explored, and optimum conditions for the preparation of spiro[bicyclo[2.2.1]heptane-2,1′-cyclopentan]-3-one have been established. 3-exo-(4-Bromobutyl)norcamphor was isolated and characterized as a reaction intermediate. A series of spironorcamphors with various ring sizes were obtained in good yields using a 1:1.5:2.5 ratio of norcamphor/α,ω-dibromoalkanes /NaNH2 in Et2O.
13C NMR Spectra and Anomerization of cis- and trans-5-Arylamino-3-isopropyl-1,2,4-trioxanes
Authors: Yamamoto Hiroshi , Hirayama Masatoshi , Akutagawa Masamoto , Nishio Takehiko , Kashima Choji , Omote Yoshimori
Published: July 2006

The cis and trans isomers of 3-isopropyl-6,6-dimethyl-5-arylamino-1,2,4-trioxanes have been clearly identified and the anomerization of arylaminotrioxanes has been detected by the 13C NMR spectra in chloroform-d.
Halogenation Using Quaternary Ammonium Polyhalides. XI. Bromination of Acetanilides by Use of Tetraalkylammonium Polyhalides
Authors: Kajigaeshi Shoji , Kakinami Takaaki , Yamasaki Hiromichi , Fujisaki Shizuo , Okamoto Tsuyoshi
Published: July 2006

The reaction of acetanilides with tetraalkylammonium polyhalides, such as tetrabutylammonium tribromide, benzyltrimethylammonium tribromide, and benzyltrimethylammonium chlorobromate(1–), in dichloromethane-methanol at room temperature gave bromosubstituted acetanilides in good yields, respectively.
Hydrostannation and Hydrogermylation of Allenes
Authors: Ichinose Yoshifumi , Oshima Koichiro , Utimoto Kiitiro
Published: July 2006

Treatment of allenes with Ph3SnH or Ph3GeH in the presence of Pd(PPh3)4 catalyst provides the corresponding allylic stannanes or allylic germanes in good yields. Et3B induced radical addition of Ph3SnH or Ph3GeH to allenes are also described.
A Conductance Study of 1 : 1 Complexes of 1,2-Bis[2-(2-methoxyethoxy)ethoxy]benzene (Noncyclic Polyether) with Alkali Metal Ions in Nonaqueous Solvents
Authors: Takeda Yasuyuki , Sakamoto Shinichi , Ohashi Naohiko , Fukada Naoaki
Published: July 2006

Conductivities of alkali metal salts in the presence of 1,2-bis[2-(2-methoxyethoxy)ethoxy]benzene (AC·B18C6), which is a linear counterpart of benzo-18-crown-6 (B18C6), were measured at 25 °C in acetonitrile, propylene carbonate, and methanol. Formation constants and limiting ionic molar conductivities of the 1 : 1 AC·B18C6–alkali metal ion complexes were determined. Selectivity of AC·B18C6 for alkali metal ions is lower than that of B18C6. The selectivity order of AC·B18C6 for K+, Rb+, and Cs+ is consistent entirely with that of B18C6 (K+>Rb+>Cs+), but the selectivity order of AC·B18C6 for Na+ differs from that of B18C6. The AC·B18C6–alkali metal ion complex is less stable than the corresponding B18C6 complex. The AC·B18C6 complex may be entropy-destabilized due to the two flexible arms. The AC·B18C6–alkali metal ion complex is more mobile than the corresponding B18C6 complex; the mobility of the AC·B18C6 complex is less sensitive to a variety of the alkali metal ions in the complexes than that of the B18C6 complex. This indicates that the alkali metal ion in the AC·B18C6 complex is coordinated with the two arms and the surface charge of the alkali metal ion in the AC·B18C6 complex is more effectively shielded than that in the B18C6 complex.
Surface Properties of Microcrystalline Hydrous Titanium Oxide as Obtained by Thermal Hydrolysis from a TiCl4 Solution
Authors: Ooi Kenta , Miyai Yoshitaka , Katoh Shunsaku , Sugasaka Kazuhiko
Published: July 2006

The surface properties of hydrous titanium oxides (HTiO’s), as obtained by refluxing TiCl4 or ureacontaining TiCl4 solutions at 373 K, were examined by means of nitrogen adsorption/desorption at 77 K and of fluoride ion adsorption. Their crystal phases and particle shapes were investigated by X-ray diffraction analyses and electronmicroscopic observations, respectively. The HTiO obtained from a 0.03 or 0.1 mol·dm−3 TiCl4 solution was of an anatase type, consisting of small (about 10 nm) particles. They had pores that were 2 nm in radius, with an narrow size distribution. The HTiO obtained from a 1.0 mol·dm−3 TiCl4 solution was of a rutile type, consisting of acicular particles. It had pores that were greater than 2 nm in radius, with a broad size distribution. All of the HTiO’s obtained from (TiCl4+urea) solutions were anatase types. The most probable pore radius increased from 1.9 to 3.6 nm with the increase in the initial TiCl4 concentration from 0.03 to 1.0 mol·dm−3. The surface properties of the anatase-type HTiO’s were discussed based on the sizes and shapes of the primary crystallites and on their spatial distribution.
Binding Aspects of 2-(4-Hydroxyphenylazo)benzoic Acid to Bovine Serum Albumin in the Limited Mixing Ratio
Authors: Takeda Kunio , Sasa Katsushi , Hachiya Kazuaki , Murata Mamoru , Aoki Koichiro
Published: July 2006

The binding of 2-(4-hydroxyphenylazo)benzoic acid (HABA) to bovine serum albumin (BSA) was studied in a dilute phosphate buffer of pH 7.0 and ionic strength 0.014 at 25 °C. Binding measurements were made for both undefatted BSA and defatted BSA (the protein naturally contains 2.4–2.5 mol/mol fatty acid). A metachromasy band appeared at 480 nm at the expense of the original absorption band at 350 nm in the presence of BSA. An isosbestic point in the absorption spectra was observed in the vicinity of 380 nm only in the limited range of the molar mixing ratios of HABA to BSA (D0⁄P0), where the ratio was 1–10 in the above buffer, regardless of the absence and presence of fatty acids. However, the isosbestic point was not observed by any feasible change of the D0⁄P0 ratio in a buffer containing 0.1 M NaCl. This fact seemed to indicate that the binding nature depended on the ionic strength as well as the D0⁄P0 ratio. Then, binding measurements were carried out in the limited range of D0⁄P0 ratios in a dilute phosphate buffer. The amount of HABA bound to BSA was determined by curve-fitting for changes of the apparent molar extinction coefficient, ε, between 300 and 550 nm, assuming one class of binding site: that is, only two species (free and bound dyes) contributing to the absorption changes. The simulated curves of ε were in good agreement with those obtained experimentally. By the use of the Scatchard plot, the binding parameters were determined. The binding constant was larger for defatted BSA than for undefatted BSA, the values being of the order of 105 M−1. The number of binding sites of HABA was 1.4–1.5, not being affected very much by the absence and presence of fatty acids.
Relaxation of Short-Lived 57Fe-Species in 57Co-Labeled Co(IO3)2 Studied by Time-Resolved Emission Mössbauer Spectroscopy
Authors: Watanabe Yasuo , Endo Kazutoyo , Sano Hirotoshi
Published: July 2006

KX-Ray-gated and time resolved emission Mössbauer spectra of 57Co-labeled Co(IO3)2 were measured at room temperature, using a coincidence technique. No remarkable difference was found on the relative intensity of Fe(II)/Fe(III) between the X-ray-gated and normal emission spectra. A lifetime for unstable 57Fe(II)-species formed through EC-decay was estimated to be 43±5 ns and the initial distribution of Fe(II)/Fe(III) at 14.4 keV nuclear level to be 0.47±0.13 from the time-resolved emission Mössbauer spectrum. The results are discussed in terms of the chemical stability of the environments of the decayed 57Fe-atoms.
The Effect of Water Vapor on the Thermal Decomposition of Various Tin(IV) cyclo-Phosphates
Authors: Nariai Hiroyuki , Motooka Itaru , Tsuhako Mitsutomo
Published: July 2006

The process of the thermal decomposition of various tin(IV) cyclo-phosphates, SnP4O12·4H2O(P4m), Sn3(P6O18)2·12H2O (P6m), and Sn2P8O24·5H2O(P8m), was investigated using X-ray analysis, DTA-TG, and HPLC-FIA. P4m lost the water of crystallization at about 105 °C. In the region of 400–500 °C, P4m changed to cyclo-triphosphate (P3m) without any other species of phosphates. Therefore, the change of P4m to P3m probably proceeded as a radical reaction. At temperatures above 580 °C, P3m changed to insoluble polyphosphates (Phigh poly). P6m lost the water of crystallization at about 110 °C. In the region of 500–570 °C, P6m changed to Phigh poly through P3m. P8m lost the water of crystallization at about 140 °C. At about 255 °C, P8m decomposed to oligo phosphates(n<8)(Poligo), soluble polyphosphates(15<n<20)(Ppoly), and amorphous insoluble polyphosphates (Phigh poly*). Under a higher water vapor pressure, these decomposition and subsequent condensation reactions proceeded rather faster than in a lower one. At about 300 °C, Phigh Poiy* changed to P3m again. At higher temperatures, P3m changed to Phigh poiy.
The Crystal Structures of Δ-, Λ-, and Pseudoracemic Forms of Bis(ethylenediamine)oxalatocobalt(III) Aspartates
Authors: Kiriyama Hideko , Igaki Michihito
Published: July 2006

The crystal structures of Δ-[Co(ox)(en)2](l-Hasp)·3H2O, Λ-[Co(ox)(en)2](l-Hasp)·3H2O and rac[Co(ox)(en)2](l-Hasp) have been determined by means of X-ray diffraction. The absolute configurations of (−)-and (+)-cations were assigned as Δ(δλ) and Λ(δλ), respectively, on the basis of that of l-Hasp− ion. The counter ion is extended with C–C–C–C near 180° in all cases, but the other torsion angles are somewhat affected by surroundings. Both α and β carboxyl groups of the anion are ionized, therefore its NH2 group is protonated. In the three compounds, the cations and the anions are alternately arranged, forming a layer through N–H···O hydrogen bonds in a very similar way to each other. The lattice of the more soluble Δ-isomer consists of such single cation–anion layers, between which water molecules are inserted. In the less soluble Λ-diastereoisomer the cation–anion layers are doubled by N–H···O bonds between cations from neighboring layers. The less soluble racemic salt is anhydride where the similar cation–anion layers are connected by hydrogen bonds between cations and between anions alternately. In connection to optical resolution, the difference in solubility was discussed in terms of the density, unoccupied fraction and electrostatic energy.
Studies on the Reaction Products of Antitumor Platinum Complex with d(ApG), d(GpA), and d(pGpA). 2′-Deoxy Sugar Is Favourable for G-N7, A-N1 Chelation
Authors: Inagaki Kenji , Tomita Akihito , Kidani Yoshinori
Published: July 2006

The reaction products of dichloro[(1R,2R)-1,2-cyclohexanediamine]platinum(II), Pt(R,R-dach)Cl2, with dinucleotides, d(ApG), d(GpA), and d(pGpA) have been separated by HPLC, and each product fractionated has been characterized by UV and CD spectral analyses. The reaction of Pt(R,R-dach)Cl2 with d(ApG) yields Pt(R,R-daich)(d(ApG)-N1(1),N7(2)) (1, 16%), Pt(R,R-dach)(d(ApG)-N7(1),N7(2)) (2, 80%) and uncharacterized minor product (4%). The reaction with d(GpA) yielded two Pt(R,R-dach)(d(GpA)-N7(1),N1(2)), (3, 22% and 5, 61%), and Pt(R,R-dach)(d(GpA)-N7(1),N7(2)), (4, 17%), but surprisingly 5 isomerizes very slowly to 3 and 4 under the subsequent incubation (half life of 5; about 6 days at 37 °C). The reverse reaction (3 and 4→5) was not observed. The reaction with d(pGpA) also yielded two Pt(R,R-dach)(d(pGpA)-N7(1),N1(2)), (3′, 8% and 5′, 80%) and Pt(R,R-dach)(d(pGpA)-N7(1),N7(2)), (4′, 12%). The adduct, 5′, also isomerizes to 3′ and 4′. The platinum adducts, 3′, 4′, and 5′, are compatible with 3,4, and 5, respectively, after removal of the 5′-phosphate group upon treatment with alkaline phosphatase. A competition reaction between d(ApG) and d(GpA) for Pt(R,R-dach)Cl2 indicates that d(ApG) was about 2 times more reactive than d(GpA). The reactivity decreases along the series; d(pGpA)>d(ApG)>d(GpA).
Synthesis and Properties of Copper(II) Thiocyanato Complexes with Imino Oximes
Authors: Wan Songping , Mori Wasuke , Yamada Shoichiro , Murahashi Shun-Ichi
Published: July 2006

Reaction of copper(I) thiocyanate with imino oximes 3-[[2-(alkylamino)ethyl]imino]-2-butanone oximes or 3-[[2-(dialkylamino)ethyl]imino]-2-butanone oximes, (abbreviated as Hdox-enRR′), gave a series of copper(II) complexes which consist of binuclear complexes [Cu2(dox-enRR′)2(NCS)2] with a thiocyanate anion coordinated to the copper(II) ion. The magnetic susceptibilities over the temperature range 77–320 K show a strong antiferromagnetic spin coupling through the N–O bridge for these complexes. The magnetic behavior can be explained by using the Bleaney–Bowers equation.
Photochemical Alkylation, Hydroxyalkylation, and Alkoxylation of Pyridinecarboxamides in Alcohol
Authors: Sugimori Akira , Itoh Hiroshi , Kanai Mitsuharu , Itoh Nobuko , Sugiyama Toru
Published: July 2006

The UV-irradiation of 2- and 4-pyridinecarboxamides in alcohol brings about alkylation and/or hydroxyalkylation in the pyridine ring. In the irradiation of 3-pyridinecarboxamide in the presence of sulfuric acid, ionic reaction (alkoxylation at the 2- and 6-position) and radical reaction (alkylation at the 4- and 6-position) occur in parallel. The effects of quenchers indicate that two alkylation products originate from one excited triplet state which is quenched by energy-transfer mechanism and that two alkoxylation products originate from the excited singlet state.
Novel Sulfur-Containing Phytoalexins from the Chinese Cabbage Brassica campestris L. ssp. pekinensis (Cruciferae)
Authors: Takasugi Mitsuo , Monde Kenji , Katsui Nobukatsu , Shirata Akira
Published: July 2006

The first isolation and structure elucidation of four sulfur-containing indole phytoalexins from Chinese cabbage inoculated with Pseudomonas cichorii are described.