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111.
K. Matsuo Y. Gosho T. Toyoda Y. Sonoda K. Muraoka M. Akazaki 《International Journal of Infrared and Millimeter Waves》1985,6(10):1051-1059
This paper is concerned with systematic developments of the Fraunhofer-diffraction method for studies of plasma density fluctuations in high-temperature plasmas using infrared lasers, namely (i) development of the general theory of the Fraunhofer-diffraction method, (ii) measurements of fluctuations propagating in an azimuthal direction, (iii) measurements of fluctuation intensities, and (iv) application in measurements on high-temperature plasmas. 相似文献
112.
113.
Selenium assisted carbonylation of alkyl aryl ketones with carbon monoxide leading to formation of 1,3-dicarbonyl compounds as C-carbonylated products is described. o-Hydroxyacetophenone 7a and its derivatives7b,7c, and 7d have been converted to the corresponding 4-hydroxycoumarins 8a,8b,8c and 8d in moderate to quantitative yields by treatment with an equivalent of selenium and carbon monoxide with concomitant formation of hydrogen selenide 9 (Eq.(8)). It was further revealed that oxidation of in situ formed hydrogen selenide to selenium with an appropriate oxidizing agent such as nitrobenzene permitted catalytic use of selenium for the carbonylation of 7. Possible rationalizations for the formation of 4-hydroxycoumarins are suggested. 相似文献
114.
Tobe Y Umeda R Sonoda M Wakabayashi T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(5):1603-1609
Multicyclic cagelike cyclophanes 2 a and 2 b containing cyclobutene rings have been prepared as precursors of three-dimensional polyynes C78H18 (1a) and C78H12Cl6 (1b), respectively. Laser irradiation of 2a and 2b induced expulsion of the aromatic fragment, indane, to give the three-dimensional polyyne anions C78H18- and C78H12Cl6-, respectively. Whereas the former anion lost only four hydrogen atoms to form C78H14-, complete loss of all hydrogen and chlorine atoms was observed from the latter anion, to yield a C78- ion that has a fullerene structure which was proven by its characteristic fragmentation pattern. 相似文献
115.
Summary Capillary gel electrophoresis (CGE) has been recognized as an effective method for the analysis of oligonucleotides. CGE using
polymer solutions is especially useful and effective compared with that using crosslinked gels, because of easy change of
media. Replacement of media leads to the reproducible separation of analytes. We have investigated CGE analysis of oligonucleotides
of less than 20 bases employing various kinds of polymers. Polyacrylamide, dextrin, dextran, pullakin, and poly(ethylene glycol)
were used as sieving matrixes at concentrations of 0–30 %. Polydeoxythymidylic acids [p(dT)11–20] were used as a test sample. These small oligonucleotides were successfully resolved on the basis of their base number by
CGE using some of these polymer solutions. In particular, dextran was found to be effective and baseline separation was observed
when a 30 % dextran solution was employed. Some validations such as linearity and reproducibility were also established and
this method was found to be an adequate quality control method for small oligonucleotides. Finally, CGE using a 30 % dextran
solution was successfully applied to impurity profiling of some synthetic oligonucleotides. 相似文献
116.
Yoichi Ikeda Sohko Motoune Aya Marumoto Yoh Sonoda Fumitoshi Hirayama Hidetoshi Arima Kaneto Uekama 《Journal of inclusion phenomena and macrocyclic chemistry》2002,44(1-4):141-144
The effect of 2-hydroxypropyl--cyclodextrin (HP--CyD) on the release of a water-soluble 1-selective adrenoreceptor antagonist, metoprolol (Met), from ternary Met/HP--CyD/ethylcellulose (EC) tablets was investigated. The release rate of Met from the ternary tablets was dependent on amounts of HP--CyD in the tablets, i.e., the rate decreased when small amounts of HP--CyD were added, while large amounts of HP--CyD accelerated the rate. The slowest rate was observed for the tablet consisted of a 30/10/60 weight ratio of Met/HP--CyD/EC. The analyses of the release rates by the Korsmeyer equation and their temperature dependence suggested that Met is released from the EC matrix containing HP--CyD according to the diffusion-controlled mechanism. The water penetration studies and the micro- and macroscopic observations suggested that the retarding effect of HP--CyD is attributable to a viscous gel formation in small pores on the surface of the tablets, where HP--CyD gels may work as a barrier for the water penetration into the tablets and the release of the drug from the tablets. The in-vitro release property of the ternary tablets was reflected in the in-vivo absorption profile in dogs. The results indicated that a combination of HP--CyD and EC is useful for the release control of water-soluble drugs such as Met. 相似文献
117.
Dithioacetals were reduced by 1,4-cyclohexadiene in the presence of a catalytic amount of Lewis acid to afford the corresponding sulfides in good yields. 相似文献
118.
Yoriko Sonoda Seiji Tsuzuki Nobuyuki Tamaoki Midori Goto 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(3):o196-o200
The crystal structures of the four E,Z,E isomers of 1‐(4‐alkoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, namely (E,Z,E)‐1‐(4‐methoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, C19H17NO3, (E,Z,E)‐1‐(4‐ethoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, C20H19NO3, (E,Z,E)‐1‐(4‐nitrophenyl)‐6‐(4‐n‐propoxyphenyl)hexa‐1,3,5‐triene, C21H21NO3, and (E,Z,E)‐1‐(4‐n‐butoxyphenyl)‐6‐(4‐nitrophenyl)hexa‐1,3,5‐triene, C22H23NO3, have been determined. Intermolecular N⋯O dipole interactions between the nitro groups are observed for the methoxy derivative, while for the ethoxy derivative, two adjacent molecules are linked at both ends through N⋯O dipole–dipole interactions between the N atom of the nitro group and the O atom of the ethoxy group to form a supramolecular ring‐like structure. In the crystal structures of the n‐propoxy and n‐butoxy derivatives, the shortest intermolecular distances are those between the two O atoms of the alkoxy groups. Thus, the nearest two molecules form an S‐shaped supramolecular dimer in these crystal structures. 相似文献
119.
Hisaki I Eda T Sonoda M Niino H Sato T Wakabayashi T Tobe Y 《The Journal of organic chemistry》2005,70(5):1853-1864
To generate dibenzotetrakisdehydro[12]- and dibenzopentakisdehydro[14]annulenes ([12]- and [14]DBAs) having a highly deformed triyne moiety, [4.3.2]propellatriene-anneleted dehydro[12]- and dehydro[14]annulenes were prepared as their precursors. UV irradiation of the precursors resulted in the photochemical [2 + 2] cycloreversion to generate the strained [12]- and [14]DBAs, respectively. The [12]DBA was not detected by 1H NMR spectroscopy, but it was intercepted as Diels-Alder adducts in solution, suggesting its intermediacy. Its spectroscopic characterization was successfully carried out by UV-vis spectroscopy in a 2-methyltetrahydrofuran (MTHF) glass matrix at 77 K and by FT-IR spectroscopy in an argon matrix at 20 K. On the other hand, the [14]DBA was stable enough for observation by 1H and 13C NMR spectra in solution, though it was not isolated because of the low efficiency of the cycloreversion. The [14]DBA was also characterized by interception as Diels-Alder adducts in solution and by UV-vis spectroscopy in a MTHF glass matrix at 77 K. The kinetic stabilities of the DBAs are compared with the related dehydrobenzoannulenes with respect to the topology of the pi-systems. In addition, the tropicity of the [14]DBA is discussed based on its experimental and theoretical 1H NMR chemical shifts. 相似文献
120.
Koichi Yamaguchi Osamu Sonoda Yuji Minoura 《Journal of polymer science. Part A, Polymer chemistry》1972,10(1):63-76
The polymerization of vinyl monomers with various xanthates (potassium tert-butylxanthate, potassium benzylxanthate, zinc n-butylxanthate, etc.) were carried out at 0°C in dimethylformamide. N-Phenylmaleimide, acrylonitrile, methyl vinyl ketone, and methyl methacrylate were found to undergo polymerization with potassium tert-butylxanthate; however, styrene, methyl acrylate, and acrylamide were not polymerized with this xanthate. In the anionic polymerization of methyl vinyl ketone with potassium tert-butylxanthate, the rate of the polymerization was found to be proportional to the catalyst concentration and to the square of the monomer concentration. The activation energy of methyl vinyl ketone polymerization was 2.9 kcal/mole. In the polymerization, the order of monomer reactivity was as follows: N-phenylmaleimide > methyl vinyl ketone > acrylonitrile > methyl methacrylate. The initiation ability of xanthates increased with increasing basicity of the alkoxide group and with decreasing electronegativity of the metal ion in the series, lithium, sodium, and potassium tert-butylxanthate. The relative effects of the aprotic polar solvents on the reactivity of potassium tert-butylxanthate was also determined as follows: diethylene glycol dimethyl ether > dimethylsulfoxide > hexamethylphosphoramide > dimethylformamide > tetrahydrofuran (for methyl vinyl ketone); dimethyl sulfoxide > hexamethylphosphoramide > dimethylformamide ? diethylene glycol dimethyl ether (for acrylonitrile). 相似文献