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1,3-Dioxep-5-ene was arylated by using Heck reaction, and the arylated 1,3-dioxep-4-ene derivatives were easily converted into 4-arylbutyrolactones, intermediates for the synthesis of natural products and biological active compounds

Indolylzinc derivatives were prepared by the oxidative addition of active zinc to iodoindoles, which coupled with aromatic halides in the presence of palladium catalyst to give arylated indoles.

3-Methyleneindoline derivatives were synthesized by intramolecular Heck reaction of N-allyl-2-iodoaniline derivatives in the presence of Ag2Co3. This method was successfully applied to the synthesis of the CC-1065/duocarmycin pharmacophore.

1, 3-Dipolar cycloaddition reaction of trimethylstannylacetylene with nitrile oxides yielded 3-substituted 5-(trimethylstannyl)isoxazoles. On the other hand, the same reaction of (trimethylstannyl)phenylacetylene, -1-hexyne, and -(trimethylsilyl)acetylene gave 3, 5-disubstituted 4-(trimethylstannyl)isoxazoles almost regioselectively. The regioselectivity of the cycloaddition reaction is interpreted by application of the frontier-electron theory.

Palladium-catalyzed reaction of aryl and heteroaryl iodides with ethoxy(trialkylstannyl)acetylenes gave the ethoxyethynylarenes and -heteroarenes, which were easily transformed by hydration reaction into ethyl areneacetates and heteroareneacetates.

The marine alkaloid rigidin has been synthesized from 2,4-dimethoxy-7-phenylsulfonylpyrrolo[2,3-d]pyrimidine. Lithiation of the pyrrolo[2,3-d]pyrimidine followed by electrophilic substitution with N, 4-dimethoxy-N-methylbenzamide afforded a 6-(4-methoxy)benzoyl derivative which by alkaline hydrolysis and subsequent iodination was converted into 2,4-dimethoxy-5-iodopyrrolo [2,3-d] pyrimidin-6-yl 4-methoxyphenyl ketone. The palladium-catalysed arylation of this with 2-(4-methoxyphenyl)-1,3,2-dioxaborinane followed by demethylation with boron tribromide gave rigidin.

The A 12p peak was found near 74.7 eV and F 1s peak was located near 683.7 eV for the glasses in the system Alz.sbnd;Cdz.sbnd;Pbz.sbnd;Oz.sbnd;F. With the increase in the F O ratio, the F 1s binding energy decreased and that of Al 2p increased. It is concluded that most of F ions are under ionic interaction with Cd and Pb, and that the rest of F ions substitute O in AlXn polyhedra n = 4 or 6; X = F+O as the F O ratio increases.

GeO(2) - SiO(2) thin glass films were prepared by the rfsputtering deposition method. Changes in the refractive index of -3% and in the volume of +18% were induced in the film by irradiation with excimer-laser pulses. Bragg gratings a (periodic surface-relief pattern with a sinusoidal wave) have been written in the film by irradiation through a phase mask.

The palladium-catalyzed cross-coupling reaction of bromobenzenes or bromoheteroarenes such as pyridine, thiophene, indole with ( Z )-1-ethoxy-2-tributylstannylethene gives good yields of the corresponding ( Z )-1-ethoxy-2-(aryl and heteroaryl)ethenes. This method is effective for introducing an ethoxyethenyl group into an aromatic and heteroaromatic ring and is proved to have versatile utility for the construction of benzo[ b ]furan, indole, isocoumarin rings from 2-bromophenol, 2-bromoaniline, and 2-bromobenzoate derivatives.

A quantitative structural model of oxyfluoride glasses in the system SnPbPFO is proposed on the basis of IR, XPS, NMR and Mossbauer spectroscopy. The main structure of the glass is that phosphorus tetrahedra [PO4−xFx] (x = 0, 1, 2) including PF bonds connected to each other by intervening Sn(Pb) or SnO(PbO). This gives rise to the network of the OPOSn linkage. Besides, there are Sn(Pb)F bonds in this structure. The existence of covalent and less polar PF bonds results in the molecular nature in the structure of the glasses. This enables one to introduce organic molecules into the glasses.

3-Substituted 5-(tributylstannyl)isoxazoles were newly synthesized by the 1,3-dipolar cyctoadditton of nitrile oxides to tributylethynylstannane. The iodination and the palladium-catalyzed benzoylation of 5-(tributylstannyl)-3-methylisoxazolegave 5-iodo-3-methylisoxazole and 3-methyl-5-isoxazolyl phenyl ketone in satisfactory yields, respectively. The palladium-catalyzed cross-coupling reaction of the stannylisoxazole with 2-bromonitrobenzene followed by the catalytic hydrogenation over Raney nickel resulted in the formation of 2-methyll-4(1H)-quinolinone in 57% overall yield.

Diglycolic acid (DGA) oxidizing activity was found in crude extracts of Rhodococcus sp. no. 432 grown in DGA. Glycolic acid (GA) oxidase was purified approximately 80 times by treatment with streptomycin sulfate, precipitation with (NH4)2SO4, chromatographies with DEAE-cellulose, DEAE-Toyopearl and Butyl-Toyopearl, and gel filtration on Toyopearl HW-55. The purified GA oxidase was almost homogeneous on sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis. The purity was calculated to be more than 95%. The molecular weight of the enzyme, which appeared to consist of three identical units, was 158,000. Each subunit of GA oxidase included one molecule of FAD as a cofactor. The isoelectric point of the enzyme was around 5.3. GA oxidase was stable below 30°C and at the pH range of 6.0–8.5. The optimum pH and temperature were around 7.5 and 40°C, respectively. Oxygen, cytochrome c, ferricyanide and 2,6-dichlorophenol indophenol (DCIP) acted as an electron acceptor. The activity of GA oxidase was strongly inhibited by potassium cyanide, quinine, quinacrine, monoiodoacetate, 1,4-benzoquinone and some heavy metal ions. GA oxidase also had activity in DGA, GA, glyoxylic acid (GOA), methoxy acetate, ethoxy acetate and l -malate. Alcohols and other organic acids were not oxidized by the enzyme. The apparent Km values for DGA, GA and GOA were about 26.7, 0.5 and 4.4 mM, respectively. The reaction products from DGA were supposed to be GOA and GA by the enzymatic assays. The reaction mechanism of GA oxidase in oxidation of DGA was supposed to be as follows: HOOCH2COCH2COOH+H2O+acceptor→HOOCCHO+HOOCCH2OH+ reduced acceptor.

Photon-induced property changes of sputter-deposited GeO(2)-SiO(2) thin glass films were investigated. Irradiation with ArF laser pulses induced the changes in refractive index of -10% and volume of +30% in the film without ablation. A Bragg grating with a positive sinusoid wave pattern was printed upon the film by irradiation with ArF excimer laser pulses through a phase mask. The irradiated area could be quickly etched by a HF solution. The ratio of etching rate of irradiated area to unirradiated area was higher than 30. A Bragg grating with a surface relief pattern was successfully formed on the film by irradiation with excimer laser pulses followed by chemical etching. Diffraction efficiency of the gratings increased by 25 times with the etching.

The palladium(0)-catalyzed condensation of aryl halides with the sodium salts of phenylsulfonylacetonitrile and diethyl cyanomethylphonate in dimethoxyethane gave the corresponding α-phenylsulfonylareneacetonitriles and diethyl arylcyanomethylphosphonates in good yields.The α-phenylsulfonylareneacetonitriles were easily desulfonylated with zinc to give the areneacetonitriles, and the arylcyanomethylphonates were converted to the alkylideneareneacetonitriles by means of the Horner-Emmons reaction.

Palladium-catalyzed cyclization of β-(2-halophenyl)amino substituted α,β-unsaturated ketones and esters, prepared from 2-haloanilines by three different methods, gave 2,3-disubstituted indoles.

Highly sensitive piezoelectric ultrasonic micro-sensors with a grooved multilayer membrane have been developed by Si-based MEMS technique. The groove was located at one-quarter of the membrane and opened in piezoelectric layer. The piezoelectric layer PZT is 2.2 mum thick and was prepared by sol-gel method. The prepared PZT films shows pure perovskite and high (100) textured strucure. The sensitivity of the fabricated piezoelectric ultrasonic sensor without the groove structure is 100 muV/Pa. On the other hand, the sensitivity of the ultrasonic sensor with the groove structure is about 500 muV/Pa, which is 5 times higher than that without the groove structure. The diaphragm having grooves shows a corrugate-like structure that was formed by residual stress. The high sensitivity of the membrane with the grooved diaphragm is considered to relate with the corrugate-like structure.

As self-loosening of nuts is really a problem for bolted joints in practical use, countermeasures for the loosening is highly required. In this situation non-loosening fasteners are one of the resolutions for any fastened machinery as an essential mechanical element. Self-loosening of threaded bolt/nut systems has been researched in number of works and most researches were based on experiment and a few were based on the finite element analysis in these years. Using this new approach, various types of nuts can also be examined. Among these nuts eccentric nuts and slit nuts are especially expected to be the solution, as these nuts are reported to endure NAS vibration tests and were not loosened. In the authors’ previous paper, an eccentric nut and a normal nut were analyzed and compared in the aspect of loosening property. In this paper degree of loosening of various nuts was investigated by experiment and the FEA.Copyright © 2007 by ASME

Bolted joints have been used in mechanical structures. However, loosening accidents sometimes happen under several types of loadings. Recently, some studies have been conducted on the screw thread loosening in bolted joints. It is verified that bolted joints are loosened when transverse repeated loadings are applied. Some studies on no rotational loosening in bolted joints under thermal changes have also conducted. However, few studies on rotational screw thread loosening in bolted joints have conducted. In this study, rotational screw thread loosening in bolted joint under repeated temperature changes is examined. Effects of the linear thermal expansion coefficient of clamped parts and number of repeated temperature changes are examined by the measurements and finite element analyses. In the experiments, a bolted joint, which consist of two rectangular plates fastened at room temperature by two bolts and nuts, are put in a furnace and heated by an electric heater. Then, the bolted joint is cooled at room temperature. These thermal cycles are repeated. Bolt temperature and bolt load were measured. Loosening is evaluated from the reductions in the bolt load. Finite element analyses were carried out for clarifying the loosening mechanism. Discussion is made on the mechanism of rotational screw thread loosening in bolted joints under repeated temperature changes. The results show that loosening occurs under repeated temperature changes due to difference in the linear thermal expansion coefficients of the different clamped parts.Copyright © 2007 by ASME

We report a new series of hepatitis C virus NS5B RNA polymerase inhibitors containing a conformationally constrained tetracyclic scaffold. SAR studies led to the identification of 6,7-dihydro-5H-benzo[5,6][1,4]diazepino[7,1-a]indoles (19 and 20) bearing a basic pendent group with high biochemical and cellular potencies. These compounds displayed a very small shift in cellular potency when the replicon assay was performed in the presence of human serum albumin.

In mechanical structures, a lot of bolts and nuts have been used. Sometimes loosening accidents happen in the structures under several types of loadings. Recently, the cause of the screw thread loosening is being elucidated. However, the effect of some parts for preventing the loosening in bolted joints such as spring washer, double nut and so on is not fully elucidated. In this study, the experiments were carried out to measure the reduction of axial bolt force in the bolted joint with some parts for preventing the loosening such as the spring washer, the toothed washer, the double nuts, the eccentric nut, and so on under the transverse repeated loadings. The test machine used was Junker’s type loosening machine. Then, the effects of the washers and some types of nuts are evaluated on the loosening of bolted joints. It is shown that the performance for loosening is getting better as the initial clamping force increases and the effect of the washers is not found on the loosening. However, the effect of eccentric nut is substantial on the loosening. In addition, the loosening tests according to NAS were also carried out. No effect of all the washers mentioned above is found due to NAS testing. Discussion is made on the effect of the parts for preventing the loosening mentioned above.Copyright © 2006 by ASME

2,4-Dienoyl-CoA reductases from Escherichia coli and bovine liver were purified and characterized by the authors and almost simultaneously by Kunau and his colleagues around the early 1980s. The authors purified 2,4-dienoyl-CoA reductase from rat liver, cloned its cDNA and expressed its active form in Escherichia coli for the first time. Schulz and his colleagues have elaborately shown that mutant E. coli, in which the activity of the 2,4-dienoyl-CoA reductase is reduced to 12% of that in the parental strain, can grow on oleic acid but not on (Z)-6-octadecenoic acid as a sole carbon source. A single sporadic human fatality, in which the activities of 2,4-dienoyl-CoA reductases were reduced and accumulation of (2E,4Z) 2,4-decadienoylcarnitine was observed, has so far been reported. These taken together with the discovery of a novel delta3,5-delta2,4-dienoyl CoA isomerase and the absence of 3-hydroxyacyl-CoA epimerase have caused the classical metabolic pathway for beta-oxidation of unsaturated fatty acids, depicted by Stoffel in 1965, to be rewritten, and 2,4-dienoyl-CoA reductases are now known to be essential to beta-oxidation of unsaturated fatty acids. Very recently a single amino acid substitution adjacent to the NADPH binding site has been reported in pigs, suggesting that single nucleotide polymorphism will also be found to occur in humans.

An analysis of the Ernst Horn (1774-1848) malpractice scandal at Berlin's Charité Hospital in the second decade of the nineteenth century reveals two interesting facets. One was the social pressure put upon Horn to publish detailed inside information about the hospital, which ironically was to build his reputation as a pioneering clinical psychiatrist. The other was the professional antagonism among the physicians involved in the scandal. The behaviour of J. C. Reil (1759-1813) in this affair stood in sharp contrast to that of J. G. Langermann (1768-1832) and C. W. Hufeland (1762-1836), who were in charge of the hospital's administration. Much of the deep mutual antipathy among the players may be interpreted as an antagonism between the opposing camps of statists and academicians.

Thin films (4.6 μm thick) of 5 GeO2‐95 SiO2 and 55 GeO2‐45 SiO2 (mol %) glasses were prepared by rf sputtering method in an Ar‐O2 atmosphere. An intense absorption band at around 5 eV was distinctly observed in both films after the as‐deposited films were annealed at 350 °C for 30 min in a vacuum. A part of this 5‐eV band was gradually decreased by UV irradiation. Saturated absorptivity changes (−Δα∞) of the UV bleached component, which is considered to be the origin of Hill gratings [K. O. Hill, Y. Fujii, and B. S. Kawasaki, Appl. Phys. Lett. 32, 647 (1978)] and second‐harmonic generation in SiO2 glass fibers doped with GeO2, after a prolonged irradiation were 50 cm−1 for 5 GeO2‐95 SiO2 films and 400 cm−1 for 55 GeO2‐45 SiO2 films. These values are greater by one or two orders of magnitude than those (∼2 cm−1) of bulk germanosilicate glasses prepared by the vapor axial deposition method.

1, 3-Dipolar cycloaddition reaction of trimethylstannylacetylene with nitrile oxides yielded 3-substituted 5-(trimethylstannyl)isoxazoles. On the other hand, the same reaction of (trimethylstannyl)phenylacetylene, -1-hexyne, and -(trimethylsilyl)acetylene gave 3, 5-disubstituted 4-(trimethylstannyl)isoxazoles almost regioselectively. The regioselectivity of the cycloaddition reaction is interpreted by application of the frontier-electron theory.

Copper-ruby glasses, which exhibit an absorption maximum at about 570nm, were prepared by simultaneous sputtering of copper and silica glass. The glasses turned red by heat treatment for less than 30min at 650°-800°C. The optimum heat treatment temperature was 700°C. Changes of optical absorption with heat treatment time were measured. X-ray diffraction analysis identified precipitated particles to ba Cu particles. The nonlinear optical property of these glasses was evaluated by the degenerate four-wave mixing method. The |χ(3)| value of this glass was 4.0×10-9esu at the wavelength of 532nm

Palladium-catalyzed cross-coupling reaction of iodobenzene and its 4-substituted derivatives, except for 4-nitroiodobenzene, with (Z)-1-ethoxy-2-(tributylstannyl)ethene under a carbon monoxide atmosphere (5 atm) gave the corresponding (E)-3-ethoxy-1-arylprop-2-en-1-ones in considerable yields. Syntheses of chromone and 4(1H)-quinolinone were accomplished by application of this method to 2-(methoxymethoxy)iodobenzene and ethyl 2-iodophenylcarbanylate, respectively. The results obtained on the carbonylative coupling reaction of halopyridines are also described.

The palladium-catalyzed cross-coupling reaction of aryl iodides with 3,3,3-triethoxy-1-propyne gave 1-aryl-3,3,3-triethoxy-1-propynes which were converted to the corresponding ethyl arylpropiolates. The arylpropiolates were also synthesized from the cross-coupling reactions of aryl iodides with 2-ethoxycarbonyl-1-ethynylzinc chloride or ethyl (tributylstannyl)propiolate, but the reactions were not generally applicable

The Cu(I)-catalyzed boration of an α,β-enone using a diboron is described. Combination of a Cu(I) salt and tributylphosphine is an effective catalyst system, though the individual use of Cu(I) and tributylphosphine is not active for the reaction.

A cyano group in 1, 2, 4-triaznes, regardless of its position, acted as an effective leaving group in reactions with carbanions. Thus, the reactions gave the corresponding substituted products in place of the compounds formed by addition reaction of carbanions to the cyano group. Grignard reaction of these carbonitriles is also described.

The depth profiles of glass surface layers were measured by XPS with Ar ion sputtering, although sputtering affects the glass composition. Deposited carbon was the best mask material for sputtering because of its low sputtering yield, clean surface and clear boundary. A glass surface treated by Soxhlet leaching apparatus was compared with untreated glass; their intensity ratio indicated the reasonable change of depth profile representing selective leaching of the alkali component.

SiO2 thin films containing fine Fe particles were prepared by a co-sputtering method. α-Fe particles were then formed by heat-treating the film at 650°C to 700°C. The average size of the particles was controlled by changing heat-treatment time and temperature. The magnetic properties of these samples were investigated and discussed in terms of the size of the particles. It was found that the coercivity of the sample containing α-Fe particles (average particle size = 24nm) is as large as 36 Oe which is much higher than that of the bulk Fe.

Reduction and separation of Pd were investigated in soda-lime-alumino-borosilicate glass. The dependence on raw materials, melting atmosphere, concentration of Pd and melting temperature was examined by electrochemical oxygen activity measurement, optical absorbance, X-ray diffraction and microscopic observation. Pd ions were slowly reduced during melting and metal particles were formed. The separation was enhanced in a reducing atmosphere, at high temperature, for long melting periods and with high concentration of Pd. Pd metal particles of about 10 to 30 μm in diameter were observed by SEM and X-ray diffraction.

Hydrated glass was prepared by the treatment in an autoclave. Specimen in a good state was obtained under unsaturated water vapor pressure conditions. The obtained glass has an silica-rich hydrated layer and proved to be more durable than the original glass. There are some kinds of hydroxyl species in the hydrated glass and there are some patterns in the depth profile of water, indicating that the rate-controlling process is not a simple diffusion and the hydration process is a complicated reaction depending on the conditions. Water in hydrated glass is tightly bonded and a disintegration of hydrated glass in this study occurs at more than 560°C.

Formations and durabilities of hydrated layers were compared between a soda-aluminosilicate (NAS), a soda-lime-aluminosilicate(NCAS) and a soda-lime-alumino-borosilicate(NCABS) glasses. The first step of our study was to prepare the optically transparent hydrated layers on the surface of specimens by an autoclave(400 °C, 20 kgf/cm2) treatment. Distributions of OH groups in hydrated layers were analyzed by an etch sectioning and FTIR measurement. The rates of hydration of the glasses were in the order NAS»NCAS>NCABS. The hydration of the NCABS glass, which is a modified nuclear waste glass, required the treatment longer than those of the NAS and NCAS glasses. In the second step, we investigated the durabilities of hydrated layers by immersing the specimens into a distilled water at 100 °C. The dissolutions of hydrated layers were confirmed for each glass. The dissolution rates of hydrated layers were in the order NCAS>NCABS»NAS. It has become apparent by an XPS analysis that the highest durability of the hydrated NAS glass was due to the formation of a sodium free Al2O3-SiO2 layer on the surface. The hydrated layer of the NCAS glass, while the sodium ions were almost leached out during immersion, dissolved to water most quickly than those of other glasses. In the hydrated layer of the NCABS glass, a half amount of sodium and boron ions remained and inhibited the dissolution of hydrated layer.

4,5-Diphenyl-2-ethoxypyrimidine (1), 3,4-diphenyl-6-ethoxypyridazine (2) and 2,3-diphenyl-5-ethoxypyrazine (3) were evaluated for inhibitory activity towards arachidonic acid-induced aggregation of rabbit blood platelet in vitro. 2,3-Diphenyl-5-ethoxypyrazine (3) exhibited significant inhibitory activity. Thus, various 5-substituted 2,3-bis(4-methoxyphenyl)pyrazines were synthesized by the nucleophilic substitution reaction of 5-chloro-2,3-bis(4-methoxyphenyl)pyrazine (9). In a similar manner, substituted 2,3-bis(4-methoxyphenyl)pyridines were prepared from 2,3-bis(4-methoxyphenyl)-6-methylsulfonylpyridine (17), which was synthesized by the cycloaddition retro Diels-Alder reaction of 5,6-bis(4-methoxyphenyl)-3-methylsulfonyl-1,2,4-triazine (16) with norbornadiene. Among the compounds prepared, 6-isopropoxy-2,3-bis(4-methoxyphenyl)-pyrazine (10f) showed the most potent inhibitory activity, which was more than the activity of anitrazafen[5,6-bis(4-methoxyphenyl)-3-methyl-1,2,4-triazine.

The dynamic structure of xLi2S-Ga2S3-6GeS2 (x=4 and 6) glasses has been investigated by 7Li nuclear magnetic resonance. In two samples similar values of spin-lattice relaxation time (T1) were obtained. The relaxation mechanism at 20MHz and 78MHz is therefore attributed to the local motion of lithium ions. In the glass corresponding to x=6, which shows higher conductivity, the slow motion of ions showing an activation energy of 24.3kJ/Mol has been detected by the spin-lattice relaxation time in the rotating frame (T1p). This value is comparable to the activation energy determined by the conductivity. The existence of this mode is supported by the motional narrowing of the line width which is sensitive to the motion less than 10kHz.

5,6-Diphenyl-, 3,5-diphenyl-, and 3,6-diphenyl-1,2,4-triazine (as-triazine) derivatives were evaluated for inhibitory activity towards arachidonic acid-induced aggregation of rabbit blood platelet in vitro. Among the isomers, 5,6-diphenyl-as-triazine derivatives were active, therefore a phenyl substituent on the as-triazine ring at the 5- and 6-position was essential for the inhibitory activity. Thus, various 3-substituted 5,6-diaryl-as-triazines were synthesized by the nucleophilic substitution reaction of 5,6-diaryl-3-methylsulfonyl-as-triazines with O,N,C-nucleophiles. In the case of as-triazines having different aryl groups at the 5- and 6-positions, the compounds were prepared by the step-wise addition reaction of Grignard reagents with 3-methylthio-as-triazine. Among these compounds, ethyl 5-(4-methoxyphenyl)-6-phenyl-as-triazine-3-acetate (24a) and ethyl 5,6-bis(4-methoxyphenyl)-as-triazine-3-acetate (24f) showed the most potent inhibitory activity, which was almost equal to the activity of anitrazafen.

The purpose of the present study was to assess the validity of Piezo-electric accelerometer for estimating energy expenditure in walking and jogging. Energy consumption by oxygen uptake was determined during steady state level of treadmill walking at the speed of 60, 80 and 100 m/min and jogging at the speed of 100, 120, 140, and 160 m/min for 10 subjects. There was a highly significant correlation between the energy consumption and the estimated energy expenditure by an accelerometer despite the attached position (r = 0.912 at the waist, r = 0.915 at the chest, P < 0.001), which suggests accurate estimating energy expenditure in the field.

Degenerate four-wave mixing experiments have been performed for Au colloid-doped glasses prepared by melting and sputtering methods. The nonlinear optical properties of the glasses are discussed from viewpoint of the concentration of the Au colloid particles and the thickness of the glasses. We also discuss the dependence of the nonlinear properties on the pulse duration of laser for the measurements, and a very slow relaxation.