The significance of ceramide, a main component of intercellular stratum corneum lipids, to the water-retaining ability and the barrier function of stratum corneum was investigated. A pseudo-ceramide being the analogous molecular structure to the natural occurring ceramide was synthesized according to the molecular design. The highly selective reaction of the synthesis enabled the industrial production of this synthetic ceramide. Then the artificial stratum corneum lipids, possessing self-organizing lamellar structure, were prepared by using the synthetic pseudo-ceramide in combination with amphiphilic molecules. It was confirmed that these amphiphilic molecules stabilize the lamellar association structure by intermolecular interactions thus enhancing the bound water content. Using these artificial stratum corneum lipids as the oil phase, we obtained multilamellar emulsion in which each emulsion droplet possesses a concentric lamellar structure. The multilamellar emulsion recovered the waterretaining ability of stratum corneum, which was not recovered solely by the treatment of an ordinary emulsion, and improved the scaling to restore the fine texture of the skin. It is concluded that the ceramide-based skin care products recover and maintain the physiological function of stratum corneum in the identical mechanism with intercellular stratum corneum lipids.

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Dissolution behavior of hydroxyapatite (HAP 2 g/dl) was studied in the presence of simple salts (Na2SO4, CH, COONa (=NaAc), or NaCl). Equilibrium concentrations of phosphate ([Pi]) and calcium ([Ca2+]) ions released from HAP increased with concentration of added salts. The order of salts increasing [Pi] was Na₂SO₄>NaAc>NaCl, while that increasing [Ca²⁺] was NaCl>NaAc>Na₂SO₄. The behavior of such an incongruent dissolution of HAP was explained in terms of anion and cation exchanges between constituent ions of HAP and those of added salts under a restriction of the solubility product of HAP. The degree of ion exchanges depended on the affinity and concentration of added salts. Equilibrium pH of the HAP suspension contaiing SO₄^2- was the highest due to the highest concentration of Pi released from HAP, because Pi consumesNa⁺ in a mother solution through a mechanism of protination. It was concluded that SO₄^2- has a specific affinity for HAP. This fact was confirmed by the facts that zeta potential (η) of HAP was the lowest algebraically in the presence of Na, SO₄ and that the ion size of SO₄^2- is quite similar to that of PO₄^3- although their valenc ies are different each other.

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Complex formation of hydroxoaluminum polycations and Li-fluorine micas having different layer charges, which are obtained from Na-fluorine micas, by cation exchange method, has been carried out in order to clarify the effect of interlayer cation, layer charge, and OH/A1 ratios of hydroxoaluminum solutions on the properties of complexes. While Na-micas having high layer charge cannot form complexes for the lack of swellability, those corresponding Li-exchanged micas can form complexes because of the increase of induced swellabulity: i. e., Li-micas have enough swellability to intercalate bulky hydroxoaluminum polycations regardless of the magnitude of their layer charges. However, selectivity of each Al-species in hydroxoaluminum solutions changes with increasing layer charge for the exchange reaction of intercalation with Li-micas: The ratio of intercalated Al-monomer vs. P 3 species, which corresponds to so-called [A113(OH)24(H20)12]7+species, increases with increasing layer charge at hydroxoaluminum solution having OH/A1ratio 2.09, while that of intercalated P 3 vs. P 2 species, which has nearly 6-times larger molecular weight than P 3, increases with increasing layer charge at hydroxoaluminum solution having OH/A1 ratio 2.48. Micropore volume of complexes formed decreases with increasing layer charge in despite of OFI/A1 ratios of solutions. This indicates that complexes obtained from high layer-charged micas have densely stuffed structure of pillar compounds in the interlayer region, resulting in the decrease of micropore size and volume. This can also explain the decrease of specific surface area of complexes with increasing layer charge.

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Well-formed crystals of chlorspodiosite [Ca₂ClPO₄] and chlorapatite [Ca₅Cl(PO₄)3] were grown in the Ca₂ClPO₄-CaCl₂ high-temperature solutions. Phase diagram of Ca₂CllPO₄-CaCl₂was investigated on the basis of the solubility and quenching data. Crystal growth of Ca₂ClPO₄was conducted by heating mixtures containing 5 mol% Ca₂ClPO₄ at 900, 1000, or 1100° C for 10 h, followed by cooling to 600 ° C at a rate of 5 ° C Grown Ca₂ClPO₄ crystals were up to 9 mm in size, colorless, and transparent. The crystals had the forms of rod and plate. The forms were dependent on the soak temperature. Regarding of crystal form, the grown crystals were bounded by {001}, {100}, and {110} faces. On the other hand, crystal growth of Ca₅Cl(PO₄)₃ was conducted by heating mixtures containing 15 mol% Ca₂ClPO₄ at 1200 ° C for 10 h, followed by cooling to 1050 ° C at a rate of 5 ° C 11-1 and quenching from 1050 ° C to room temperature. Grown Ca5C1(PO4)3 crystals were up to 5_mm in size, colorless, and transparent. The crystals had the form of hexagonal prism {1010} with pyramidal end faces {10i1}.

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The preparation of tris(N-salicylidenealkylaminato) Co(III) complexes (Co(salalkam)₃) is reported. In order to clarify the molecular structure and dynamic property of the Co(salalkam)₃, magnetic resonance studies of the complex were investigated in solution by ¹H-, ¹³C-, and ⁵⁹Co-NMR spectra and ¹³C, ⁵⁹Co- spin-lattice relaxation time measurements. The introduction of an alkyl group to the N-atom of salicylideneaminato group could induce the formation of the mer-complex due to the steric interaction between the substituent group and the phenyl group of the salicyl group. The coordination geometry of a salicylideneaminato ligand around a Co(III) ion was not affected by the length of N-alkyl substituents of the ligand. It is considered that in such large molecules as those investigated here, the dipole-dipole relaxation is dominant. So, molecular movement may be qualitatively discussed on the basis of the T₁ values. That is to say, ¹³C-spin-lattice relaxation times were interpreted as due to movement of the substituted alkyl groups. The T₁ values for the long alkyl substituents were much larger than those of the short alkyl (CH₃, C₂H₅, C₃H₇) substituents. This fact suggests that the rotation for short alkyl substituents would be inhibited by the coordination and the segmental movement of the alkyl groups would become more brisk along the extended carbon chains. The T₁ values for the ⁵⁹Co atom, in which nuclear quadrupolar relaxation is dominant, became smaller (from 0.64 to 0.19 ms) along the extended alkyl chains in the complexes. This means that the molecular movement of the complex would become more stagnant along the extended carbon chains.

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Molecular states of pyrene have been investigated in the ground mixtures with α-, β-, γ-cyclodextrins (CDs) and microcrystalline cellulose. In the ground mixture of pyrene with β-CD (Pyrene/β-CD=1.0), the fluorescence peak due to pyrene monomer appeared at 397 nm, which was not observed - in pyrene crystals. The fluorescence peak intensity due to pyrene monomer decreased with an increase of pyrene content in the ground mixture. Since timeresolved fluorescence analysis indicated the existence of inclusion compound in the ground mixture, it was suggested that pyrene molecules were monomolecularly included in β-CD cavities in the ground mixture. On the other hand, in the ground mixture with γ-CD (Pyrene/γ-CD=1.0), a fluorescence peak due to pyrene excimer was observed. The iden tical spectrum was observed in the inclusion compound with γ-CD. These results were interpreted in terms of the inclusion of two pyrene molecules in the γ-CD cavity. In the ground mixture with α-CD having small cavity, and in that with microcrystalline cellulose having no cavity, similar small spectral changes of pyrene were observed.

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Metacrownophanes (2) (with two methoxyl groups on the aromatic nuclei) and (3) were conveniently prepared by means of intramolecular [2+2] photocycloaddition of styrene derivatives in acetonitrile. It was suggested from the examination of ¹H-NMR spectra that the syn-conformation of the simple metacrownophane ( 3) became predominant in the presence of alkali metal salts in contrast to ( 2 ) that had anti-conformation (Table 1). When they were used as carriers for alkali metal cations with dodecanoic acid in chloroform membrane systems, crownophane ( 3 ) showed higher efficiency (especially toward Li⁺ ion) than that of (2) (Table 2), indicating its smooth conformational change between syn- and anti-form.

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Bromination of the HC1 salt of 1-methoxycarbony1-1-methyl-1, 2, 3, 4-tetrahydro-p-carboline ( 4 ) in methanol gave a 21: 79 mixture of 7-bromo-(8 a) and 6-bromo-(8 b) tetrahydro-pcarbolines. On the other hand, reaction of 2-formylated derivarive (4 b) with bromine in chloroform gave an 84: 16 mixture of 7-bromo-(8 ab) and 6-bromo-(8 bb) tetrahydro-p-carbolines. (8 a) was easily isolated by treatment of the mixture with HC1/Me0H.5-Bromo-2ethylpentanal ( 6 ) was prepared by the radical addition of hydrogen bromide to 2-(1-ethy1-3buteny1)-1, 3-dioxolane (9 a) followed by hydrolysis. Condensation of (8 a) and ( 6 ) in the p resense of sodium benzoate yielded 16-bromovincadifformine (7 c), which could be resolved to () ap. d (+)-enantiomers via diastereomeric salts of (R, R)-tartaric acid, respectively. Heating of the (+)-enantiomer in N, N-dimethylacetamide caused the racemization effectively. Compound ()-(7 c) was treated with 30%hydrogen peroxide to give 3-hydroxyaspidospermidine 9-oxide (11). The 9-oxide was reduced with Raney Ni and rearranged at pH 2.5 to afford a ca.3: 7 mixture of (+)-11-bromovincamine ( 3 ) and its epimer (13). The mixture was completely epimerized to ( 3 ) in Me0Nai Me0H.

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(+)-exo-Brevicomin of enantiomerically pure form and its (+)-endo-isomer of 77% e. e. were synthesized via lipase-catalyzed acetylation of syn-2-(1-hydroxypropy1)-6-methyl-3, 4dihydro-2 H-pyran (syn-2) and anti-2, respectively, both of which were accessible by stereoselective reduction of 2-propiony1-6-methyl-3, 4-dihydro-2 H-pyran ( 1 ). Similarly, ()-forntalin of 91% e. e. was obtained via consecutive enzymatic hydrolysis or acetylation of 2-methoxycarbony1 ( 5 ), 2-hydroxymethyl (6), and 2-acetoxymethyl derivative ( 7) of 2, 6-dimethy1-3, 4-dihydro-2 H-pyran.

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The results of molecular orbital calculation suggested that 5-thioxo-1, 5-dihydro-2 H-pyrrol2-ones (monothiomaleimides) would have higher reactivity to thiols than corresponding maleim ides. N-phenyl- and N-alkyl-substituted monothiomaleimides were prepared, and their antimicrobial activity were examined. These compounds showed good bacteriostatic activity against Gram positive bacteria such as B. subtilis and good growth inhibitory activity against yeast similar to maleimides. However they did not show bacteriostatic activity against Gram negative bacteria. Antifungal activity of N-alkyl-substituted monothiomaleimides against filamentous fungi was decreased in proportion to the increase of alkyl chain length. QSAR study of N-alkyl-substituted monothiomaleimides showed good correl arion between bacteriostatic activity against B. subtilis and hydrophobic substitution coefficient (yr). Partition coefficients (log P) of N-ethylmaleimide and its monothio analog were O.325 and 1.909, respectively. These results suggested that conversion of carbonyl moiety to thiocarbonyl moiety increased the hydrophobicity of those compounds. For the reason that increasing of hydrophobicity is more remarkable than increasing of the reactivity to SH group, it is considered that these compounds did not show better antimicrobial activity than maleimides which are lead compounds. taThe Studies on the Preparation and Antimicrobial Activity of Maleimide Compounds.

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Addition reaction of sabinene ( 1 ), isolimonene ( 2 ), r-terpinene ( 3 ), humulene ( 4), p-caryophyllene ( 5 ) and longicyclene ( 6 ) with alcohols (C1C4) in the presence of forei gn synthetic zeolites was studied, In the 300 series zeolites (HSZ-330 HUA, HSZ-340 HUA, HSZ-360 HUA), 1-alkoxy-1-p-menthene ( 9 )(11), 4-alkoxy-2-p-menthene (12)(15) and 1-alkoxy-3-p-menthene (16)(18) were obtained from ( 1 ), ( 2 ) and ( 3 ) as main products, respectively. In methanol and ethanol with 300 series (HSZ-330 HUA, HSZ-360 HUA) or 600 series zeolites (HSZ-620 HOA, HSZ-640 HOA), the addition of ( 4 ) and ( 5 ) gave 8-alkoxy-1, 4, 4, 8-tetramethy1-1, 5-cycloundecadiene (19), (20) and 1-alkoxy-4, 4, 8-trimethyltricyclo[6.3.1.02.5]dodecane (22), (23), respectively, with high selectivity. In methanol and 1-propanol with HSZ-360 HUA synthetic zeolite, 11-methoxy-1, 2, 6, 6-tetramethyltricyclo[5.3.1.02.8] undecane (28) and 8-propoxy-3, 3, 7, 9-tetramethyltricyclo[5.4.0.02.8]undecane (32) were obtained with high selectivity from ( 6 ). These compounds were evalua ted on the basis of their odor; ( 9 ), (22) especially emitted an odor that would qualify them for use as flavor materials. t Studies on the Reaction of Terpenes in the Presenec e of Synthetic Zeolites. XXI.

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The alginate is an anionic polysaccharide which is composed of 1, 4-linked p-o-mannuronic acid (M) and 1, 4-linked a-L-guluronic acid (G). It is well-known that a sodium alginate aqueous solution forms a gel by introducing divalent metal ions. In the present study, the effect of added salt on the gelation by divalent metal ions is investigated by way of rheological measurements using a cone-plate type rheometer at 25° C. The salt concentration required for gelation of the alginate aqueous solution increases in the following order; SrCl₂<CaCl₂<MgCl₂. This result is strongly related to the fact that the affinity of divalen t metal ions for the alginate decreases in the following order; Sr²⁺> Ca²⁺> Mg²⁺.

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Soot samples produced by combustion of plastics were extracted with diisopropyl ether (IPE)and were evaluated by gas chromatography/mass spectrometry (GC/MS). Specific compounds identified were chlorinated polycyclic aromatic hydrocarbons (PAHs) in poly(vinyl chloride)soots, PAHs carbonitriles in polyacrylonitrile soots, aliphatic hydrocarbons in the soots of polypropylene, poly(methyl methacrylate) and poly(4-methyl-1-pentene), the derivative of bisphenol A in polycarbonate soot etc. These compound profiles obtained from the examined twelve soots specifically changed in accordance with the chemical structures of the original plastics. These may be the indicator to identify the original plastics. In addition, dialkyl phthalates and triphenyl phosphate, which were plasticizer contained in the plastics, were also detected.

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The alumina thin films were prepared by the sol-gel method using a 1, 3-butanediol solution of aluminium nitrate. The film usually had a homogeneous flat surface. However, the surface structure of the film obtained after the immersion in a deionized water at 100°C changed to the sponze-like surface texture which was composed of fibrillay particles of 50W100 nm in length. The Al/Si intensity ratio of XRFS of the film surface decreased just after the immersion and then became roughly constant after the immersion of 2 h. Consequently, the change in the surface structure to the sponze-like texture was concluded to be due to 1)the partial dissolution of alumina particles from the substrate, and 2) the subsequent linkage between alumina particles which still remained to form stable fibrallars on the substrate. It was also found that the aluminium amount in the film can be controlled by the solution pH, temperature and the immersion time.

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Quantitative structure activity relationship of 2-arylthio-N-methylmaleimides against B. subtilis was examined, and the effects of substituents on benzene ring of those compounds were correlated with bacteriostatic activity. For p-substituted compounds, following correlative equation was introduced Also for o-subsituted compounds, following correlative equation was introduced

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In the reaction of bis(4-isocyanatophenyl)methane (BIM) with a diol mixture of poly(ethylene adipate) (Mn=2000) and ethylene glycol (molar ratio=1: 2; NCO/OH molar ratio=1.00)in bulk and in N, N-dimethylformamide (DMF), the effects of reaction temperature on the concentration of allophanate linkages in resulting polyurethanes were studied. When the reaction temperature of polyurethane formation in bulk was higher than 120 °C, increase in the reaction temperature results in decrease in the concentration of allophanate linkages. This phenomenon was explained by that the degradation of allophanate linkages was predominantly proceeded rather than their formation when the reaction temperature is higher. On the other hand, when the reaction temperature of polyurethane formation in DMF was higher than 100 °C, the polyurethane with high molecular weight was not formed because the reaction of BIM with DMF results in the deviation of NCO/OH molar ratio from 1.00. Therefore increase in the reaction temperature of polyurethane formation in DMF was inapplicable to decrease in the concentration of allophanate linkages.

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The photochemical formation of hydrogen peroxide in the Kitagata lake water was monitored by a sensitive photometric method using leuco Crystal Violet as a color producing reagent The concentration of hydrogen peroxide increased with irradiation and reached equilibrium values. Suspended solids contributed to the formation of hydrogen peroxide. The decomposition rates of hydrogen peroxide in the dark were very small compared to the formation rates. About 25% of the superoxide generated photochemically did not lead directly to hydrogen peroxide formation.

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