Studies on the synthesis of α-tocopherol have been carried out using the following two routes. First, the reaction between trimethylhydroquinone and 7, 11, 15-trimethyl-3-methylene-1, 6-hexadecadiene was examined in the presence of various Lewis acids and/or Brøonsted acids. In a model reaction using myrcene, (+) -10-camphorsulfonic acid and an aluminium chloride-tetraalkylammonium halide system were found to catalyze the Friedel-Crafts reaction between myrcene and trimethylhydroquinone to provide the desired chroman compound in good yields, while Lewis acids, such as BF₃·Et₂O or SnCl₄, gave predominantly spiro compounds. Next, the condensation reaction of trimethylhydroquinone with isophytol was examined in the presence of several kinds of Lanthanides triflates, Sc (OTf) ₃, or montmorillonite. Of these, Sc (OTf) ₃ and metal ion-exchanged montmorillonite were found to be effective catalysts giving α-tocopherol in excellent yields and purity. These catalysts worked well in various solvents and could be easily recovered and reused. These systems would be friendly to the environment and amenable to industrial-scale synthesis.

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Effect of pressure on solution properties at 40.0°C of the alkane-1-sulfonates with divalent cation of separate electric charge as counterion [1, 1'- (1, ω-ethanediyl) bispyridinium dodecanesulfonate and 1, 1'- (1, ω-decanediyl) bispyridinium tetradecanesulfonate] was examined by their critical micelle concentration (cmc). Specific conductivity of the surfactants below the cmc was found to decrease monotonously for the former but to increase for the latter with increasing pressure. This indicated that the latter surfactant with divalent counterion of longer charge separation was in associated form below the cmc and that the association decreased with increasing pressure. The cmc of both surfactants was found to have a maximum around 130 MP as conventional ionic surfactants. The volume change on micellization, ΔV_m, was evaluated from the pressure dependence of cmc, and the ΔV_m values decreased more for the former than for the latter surfactant. Static and dynamic light scatterings were determined for the micellar solutions, from which 77 and 28 were obtained for the aggregation number and 1.9 and 1.2 nm were obtained for the hydrodynamic radius for the former and the latter, respectively. The smaller aggregation number and the shorter radius were controlled by the divalent cationic counterion of longer charge separation.

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Examination was made of ceramide monohexosides and sphingophosphonolipids (SPnL) from the viscera of Euhadra hickonis. E. Hickonis belongs to Pulmonata in animal classification, and is a popular land snail in evolutional and biological respects.
Conjugated lipids were extracted with chloroform-methanol (2 : 1, by vol) following that of simple lipids with acetone. SPnL, galactosylceramide (Gal-Cer), and glucosylceramide (Glc-Cer) as main sphingolipids were separated and purified by silicic acid column and borate column chromatography. The purified sphingolipids were identified by TLC, fast atom bombardment mass spectrometry (FAB/MS), analysis of degradation products and quantitative analysis of sugar, long chain base, phosphorus and fatty acid ester.
The ceramide monohexosides consisted of 53.8% of Gal-Cer and 46.2% of Glc-Cer. The ratio of ceramide aminoethylphosphonate (CAEP) to ceramide N-methylaminoethylphosphonate (CMAEP) was about 54 : 46 in the FAB/MS positive ion mode and 73 : 27 in the FAB/MS negative ion mode. This ratio essentially the same as that for SPnL of sea abalone muscle.
The ratio of non-hydroxy fatty acid to α-hydroxy fatty acid was about 1 : 1 in SPnL, 1 : 9 in Gal-Cer, and 1 : 1 in Glc-Cer.
Main component of long chain bases of these sphingolipids was anteiso branched C19-sphingenine. The most remarkable feature of these bases in E. hickonis was the large amount of oddnumbered branched sphingenine and Pulmonata would thus appear closely related to Opisthobranchia.

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The phase behavior and the structures of self-assemblies in binary water-pure sucrose monoalkanoate (C8SE, C10SE, C12SE, C16SE) systems were investigated by small-angle X-ray scattering (SAXS). In short-chain (C8 and C10) SE systems, aqueous micelles form in a dilute region whereas the cubic phase and hexagonal liquid crystal appear at higher surfactant concentration. The cubic phase is not present in longer-chain (C12 and C16) SE systems. Krafft temperature is noted only in the C16SE-water system. Assuming the presence of cylindrical aggregates, the structure of hexagonal liquid crystals, was determined based on SAXS data. In hexagonal liquid crystals, the hydrophobic chain is in extended form in nearly all cases and the distanse between cylindrical aggregates increases with water content. A layer structure was observed at high concentration of longer-chain SE. Based on the present results, the layer structure is considered to be in a gel state.

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Examination was made of the effects of α-and β-cyclodextrins (CyD) on the acidity and ¹H NMR spectra of o and p-nitrophenols bearing a substituent (X) in aqueous solution. CyD had characteristic influence on the apparent acidity of the nitrophenols ; Δ pKa = pKa (water) -pKa (CyD) (cyclodextrin) was positive for combinations of α-or β-CyD and o-X-p-nitrophenols, and β-CyD and p-X-onitrophenols though not X=H, Me, and OMe, but negative for combinations of β-CyD and o-X-o-nitrophenols. α-CyD had sluggish effect on pKa of p-or o-substituted o-nitrophenols. It is considered that these results can be explained by how well nitrophenols (or nitrophenolates) fit into the cavity of CyD, which would be determined mainly by bulkiness, polarity and electronic properties of substituent as well as cavity size. The disposition of nitrophenolates in the cavity is discussed based on changes in the ¹H NMR spectra of the substrates in inclusion complexes.

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Synthesis of ketals of (+) -menthone (1), (+) -carvone (2), (-) -verbenone (3), (+) -camphor (4) and karahanaenone (5) by condensation reaction with ethylene glycol, 1, 2-ethanedithiol and 1, 3-propane dithiol in the presence of foreign synthetic zeolites or p-toluene sulfonic acid was developed. Ketal compounds (6) (18) were obtained and examined for oder and antimicrobial and insecticidal acitivity. (2 R, 5 S) -2-Isopropyl-5-methyl cyclohexanone propylene thioketal (8), 2-isopropyl-5-methyl phenoxy ethanethiol sulfide (13) and (1 R) -1, 7, 7-trimethyl bicyclo [2. 2. 1] heptane-2-on-propylene thioketal (16) emitted odors showing them useful as flavor ingredients.
Compound (1 R) -1, 7, 7-trimethyl bicyclo [2. 2. 1] heptane-2-on-ethylene thioketal (15) (at 500 ppm) derived from (4) completely inhibited the growth of propionibacterium acnes.
Ketal compound (15) and (16) dervied from (4) showed efficient insecticidal activity of 83100% at 0.51.0 g/m² toward Tyrophagus putrescentiae (T. putrescentiae) and Dermatophagoides farinae (D. farinae) and toward T. putrescentiae, their activity exceeded that of N, N-diethyl-m-toluamide (DEET).

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A study was made of brsssinosteroids present in seeds of Cannabis sativa L. Homogenized seeds were extracted with methanol and the extract was fractionated into a chloroform-soluble fraction, which was subsequently purified by chromatography. Bioactive substances in a rice-lamina inclination test were derivatized and analyzed by GC-MS. The brassinosteroids, castasterone and teasterone, were identified.

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The autoxidation of fish and soybean oil ceased almost completely at room temperature, when the iron powder-type free oxygen absober sealed with PE or EVA film was added to the headspace and/or into the oil phase in a sealed flask or can.

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The oxidative stability of commercial bakery products was computed directly by the conductmetric determination method (CDM) without lipid extraction from the product. Forty-three powdered samples were measured for the induction period (IP) using Methrom Rancimat 679. IP of 26 samples was rapidly determined within 50 h, but that of residual 17 samples with higher reducing suger content could not be measured owing to moderate and continuous increase in conductivity. CDM was a practical method applied to relative evaluation of oxidative stability for the bakery products.

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The oxidative coupling of p-cresol by FeCl₃ in aqueous solution was conducted in the presence of alkyltrimethylammonium bromide (C_n-TAB). Cationic surfactants greatly inhibited trimer production and increased the selectivity for dimer production. The dimer produced in the reaction system may possibly be incorporated into micelles and subsequently excluded from the aqueous oxidation system. With C₁₆-TAB, the dimer was selectively produced at a concentration above cmc. C₁₂-and C₁₀-TAB brought about selective dimerization, even below cmc.

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