Determination of the double-bond position in hexadecenols by mass spectrometry without prior chemical modification

Fourteen isomers of chemically unmodified hexadecenol were analysed by two types of quadrupole mass spectrometer, coupled with a gas chromatograph, for the location of the double-bond position. A series of spectra were interpreted in terms of mass spectral patterns on a fuzzy classification, in which the intensity ratios of six diagnostic pairs of the predominant ions were preferred in devising similarity indices. The accuracy of the method in the location of double-bond position was confirmed by testing with other series of spectra.     

Photochemical Ionic-Conductivity Switching Systems of Photochromic Crown Ethers for Information Technology

Design of two types of ion-conducting systems using photochromic crown ethers as the photocontrol agents is described; one type is based on the phase transition of azobenzene derivatives induced by their photoisomerization and the other based on the molecular control of metal ion complexation by crowned spirobenzopyrans. The photoresponsive ion-conducting systems are applicable to electrostatic imaging and photorefractive materials.     

Water‐Soluble N‐(n‐Fatty acyl)chitosans

Chitosan was partially N‐acylated by treatment with n‐fatty acid anhydrides in a homogeneous solution in 2 vol.‐% aqueous acetic acid‐methanol (1:2 v/v). The degree of substitution (d.s.) for N‐acyl groups in the water‐soluble N‐acylchitosan derivatives was in the range of 0.42–0.82 for N‐acetyl, 0.37–0.76 for N‐propionyl, 0.52–0.71 for N‐butyryl and 0.54–0.64 for N‐pentanoyl and ca. 0.58 for N‐hexanoyl, respectively.

Water soluble N‐(n‐fatty acyl)chitosans.     

Orientation control of perovskite thin films on glass substrates by the application of a seed layer prepared from oxide nanosheets

Orientation control of perovskite compounds was investigated by the application of a seed layer prepared from oxide nanosheets. An aqueous suspension of oxide nanosheets was prepared by the exfoliation of a layered compound of KCa₂Nb₃O₁₀ oxide grains. A seed layer composed of (TBA)Ca₂Nb₃O₁₀ nanosheets (TBA = tetrabutylammonium) was formed on a glass substrate by simply dip coating it in the suspension. Two kinds of perovskite compounds, LaNiO₃ (LNO) and Pb(Zr,Ti)O₃ (PZT) with a preferred orientation of (00l) were successfully grown on this seeded glass substrate. In this study, the relation between lattice mismatch and electrical properties is investigated. A large, oriented PZT film with a size of 5 ×4 cm shows an improved P-E hysteresis behavior by use of this orientation control.     

Efficient and widely applicable method of constructing neo-proteoglycan utilizing copper(I) catalyzed 1,3-dipolar cycloaddition

Efficient constructions of two types of neo-proteoglycan are described. Enzymatically prepared alkyne containing chondroitin 6-sulfate chains and chemically synthesized azido group having compounds are linked by utilizing the copper(I) catalyzed 1,3-dipolar cycloaddition.     

Synthesis and physiological activity of novel tocopheryl glycosides

Vitamin E glycosides were synthesized and enzymatic hydrolysis was examined for use as potential pro-drugs, however, the glycoside bond was found to be stable. On the other hand, among the glycosides synthesized, dl-alpha-tocopherylglucoside (6b) and dl-alpha-tocopherylmannoside (6c) showed strong inhibitory action on histamine release from mast cells. In addition, 6c also showed a suppressive action on IgE antibody formation. Thus, tocopheryl glycoside showed new properties compared to tocopherol (vitamin E). In particular, 6c was shown to be a novel lead compound with excellent manifold anti-allergic activity and anti-inflammatory activity.     

Product analyses and crosslink mechanism of plasma-polymerized methyl methacrylate

Plasma-polymerized methyl methacrylate (PPMMA) film was produced by a radio-frequency glow discharge of methyl methacrylate (MMA) gas with argon. PPMMA deposited under a plasma of mild energy was separated into a soluble fraction (sol-PPMMA) and an insoluble matrix (insol-PPMMA), which is highly crosslinked, by solvent-extraction and filtration. The chemical structure of the sol-PPMMA was determined by pyrolysis/gas chromatography, IR spectroscopy, ¹H-NMR, ¹³C-NMR, and elemental analysis techniques. On the other hand, the structure of the insol-PPMMA was examined with IR spectroscopy, ¹³C-NMR with CP/MAS method, and elemental analysis. The crosslinking mechanism in the plasma polymerization of MMA is discussed on the basis of product analyses of the sol-PPMMA and the insol-PPMMA.     

13CNMR-Untersuchung der Taktizit?t von Poly-(RS)tert-butyloxiran, das durch Polymerisation mit tert-C4H9OK erhalten wurde

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