193 research outputs found

    Biologically Active Compounds. II. The Synthesis of β-CarboxY-γ-butyrolactone Derivatives

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    Amide derivatives of γ-substituted paraconic and aconic acids have been synthesized. Ultraviolet spectra of the aconic acid derivatives showed characteristic fine structure in the region of 245 to 280 mμ

    Reaction of γ,γ-Dimethyl-α, β-dicarbethoxybutyrolactone with Acetyl Chloride

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    Acetylation of γ,γ-dimethyl-α,β-dicarbethoxybutyrolactone in benzene in the presence of sodium hydride was attempted. The structure of the condensation product was assigned to O-acetyl derivative, which was converted into γ,γ-dimethyl-β-carbethoxy-α-carboxybutyrolactone whose structure is also discussed by IR spectrum

    New Stable Sulfonium Ylides. 1-Dimethylsulfuranylidene-l-phenylsulfonyl-2-propanone and Related Compounds

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    The preparation of the title compounds as a new type of stable S-ylides has been described. The reaction of 1-dimethylsulfuranylidene-1-phenylsulfonyl-2-propanone (IIb) with lithium aluminium hydride was found to result in the formation of trans-phenylpropenylsulfone (IV), phenylsulfonyl-2-propanone (Ib), and an unidentified paraffin as major products

    Lactone Carboxylic Acids. II. Synthesis of α-Benzylideneparaconic Acids

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    The reaction of ethyl γ,γ-dialkylparaconate with aromatic aldehydes, i.e., benzaldehyde, anisaldehyde, p-chlorobenzaldehyde, and piperonal, has been investigated. The condensation took place at the α-position of the lactone ring. As the acidic components, α-benzylideneparaconic acids and α-benzylidene-β-alkylidensuccinic acids were obtained in 25-48% and 7-15% yields, respectively. From the neutral portions small amount of ethyl benzylideneparaconates were separated. During the course of distillation ethyl α-benzylideneparaconate was partially converted into α-benzylidene-γ-methy-γ-ethylbutyrolactone

    Lactone Carboxylic Acids. III. Reaction of Ethyl β-Alkylglycidates with Ethyl Malonate

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    The ring opening of epoxide group in the reaction of ethyl ,β-alkylglycidates with sodiomalonate was observed mostly at the α-position of the glycidates. Ethyl β-ethylglycidate, however, on treatment with sodiomalonate gave ten percent of β-fission product, elucidated by NMR spectra. The reaction sequence provides a general preparative route to γ-alkylparaconic acids and their derivatives

    Biologically Active Compounds. I. The Synthesis of 5-Substituted 4-Methy1-3-carboxy-3(or 4)-alkenamides

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    Monoamides of 5-substituted 4-methyl-3-carboxy-3(or 4)-alkenoic acids have been synthesized, starting with substituted itaconic anhydrides. The anhydride ring was opened by amines to afford N-aryl(or alkyl)-4-alkyl(or aryl)-3carboxy- 3(or 4}-alkenamides. The structure of the amide was elucidated by the comparison with the reference compound prepared from the corresponding Stobbe half-esters

    The Anodic Oxidation of trans-Cinnamic Acid. I. The Formation of Ketone and Aldehyde Derivatives

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    The electrochemical oxidation of trans-cinnamic acid in a mixed aqueous solution of acetic acid and methanol containing potassium hydroxide was studied. The separation of ketones and aldehydes from the neutral materials using Girard reagent P gave benzaldehyde, tolualdehydes, acetophenone, methylacetophenones, propiophenone, phenacyl acetate, and phenacyl alcohol. The mechanism of the anodic reaction of trans-cinnamic acid has been discussed

    Fatigue Crack Propagation Evaluated by Electric Resistance and Ultrasonics in Copper Film Bonded to Base Metal with Resin

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    As model specimens of surface film-bonded materials, pure copper films with a thickness of 100μm were bonded to the surface of steel base with epoxy resin, where the tensile residual stress was measured by an X-ray on the surface copper film. The distribution of initial electric resistance was measured on both copper film and base specimen by a direct current potential drop technique. As a result, there was a good agreement between the measured and theoretical values. From the fatigue testing results, it was shown that the measured electric resistance increased with the fatigue crack length on the copper film, which was almost equal to the theoretical value calculated for a central slit in a plate with finite width. This was probably because the fatigue crack was opened due to the tensile residual stress on the film even under unloading condition. In addition, the internal crack length during fatigue was examined by ultrasonic testing for the film-bonded specimen. As a result, there was a difference in the fatigue crack length between the surface copper film and the inner base

    Discovery of Molecular Loop 3 in the Galactic Center: Evidence for a Positive-Velocity Magnetically Floated Loop towards L=355359L=355^\circ-359^\circ

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    We have discovered a molecular dome-like feature towards 355l359355^{\circ} \leq l \leq 359^{\circ} and 0b20^{\circ} \leq b \leq 2^{\circ}. The large velocity dispersions of 50--100 km s1^{-1} of this feature are much larger than those in the Galactic disk and indicate that the feature is located in the Galactic center, probably within 1\sim1 kpc of Sgr A^{*}. The distribution has a projected length of 600\sim600 pc and height of 300\sim300 pc from the Galactic disk and shows a large-scale monotonic velocity gradient of 130\sim130 km s 1^{-1} per 600\sim600 pc. The feature is also associated with HI gas having a more continuous spatial and velocity distribution than that of 12^{12}CO. We interpret the feature as a magnetically floated loop similar to loops 1 and 2 and name it "loop 3". Loop 3 is similar to loops 1 and 2 in its height and length but is different from loops 1 and 2 in that the inner part of loop 3 is filled with molecular emission. We have identified two foot points at the both ends of loop 3. HI, 12^{12}CO and 13^{13}CO datasets were used to estimate the total mass and kinetic energy of loop 3 to be \sim3.0 \times 10^{6} \Mo and 1.7×1052\sim1.7 \times 10^{52} ergs. The huge size, velocity dispersions and energy are consistent with the magnetic origin the Parker instability as in case of loops 1 and 2 but is difficult to be explained by multiple stellar explosions. We argue that loop 3 is in an earlier evolutionary phase than loops 1 and 2 based on the inner-filled morphology and the relative weakness of the foot points. This discovery indicates that the western part of the nuclear gas disk of 1\sim1 kpc radius is dominated by the three well-developed magnetically floated loops and suggests that the dynamics of the nuclear gas disk is strongly affected by the magnetic instabilities.Comment: 30 pages, 10 figures. High resolution figures are available at http://www.a.phys.nagoya-u.ac.jp/~motosuji/fujishita09_figs
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