In this report, the interfacial properties of natural surfactnts (lipids) at the oil/ water interface and in a lipid bilayer were investigated. The extent of lowering of the interfacial tension, the compressibilities and collapse pressure of the mixed monolayer and permeability of the mixed bilayer are dependent on the steroids involved. The permiability and microfluidity of liposomes were also affected by the lipids.
Site-specific or site-avoidance deliveries of liposomes were also discussed using a novel synthetic lipids. Hepatic uptake of liposomes containing lactose mono-arachidic acid amide was greater than that of the control liposome and it was mostly accounted for by a greater uptake by parenchymal cells. On the other hand, a novel synthetic sialic acid derivative and phosphatidyl polyglycerols were valuable for increasing the plasma concentration and reducing the uptake of reticuloendothelial system of liposomes. It is thought that they have considerable potential for the application of liposomes as a targeting and controlled release system.

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Three terpenoid glycosides and seven phenyl propanoid glycosides were isolated from the leaves of Hiba (Thujopsis dolabrata SEIB. et ZUCC., Asunaro), and their structures were determined based on UV, MS, ¹H-NMR and ¹³C-NMR spectroscopic data. The structures were vomifoliol 9-O-β-D-glucopyranoside (1), (6R, 7E, 9R) -9-hydroxymegastigma-4, 7-dien-3-one-9-O-β-D- glucopyranoside (2), (2E, 6R) -2, 6-dimethyl-2, 7-octadien-6-ol-1-O-β-D-glucopyranoside (3), coniferin (4), 2, 3-dihydro-2- (4'-α-L- rhamnopyranosyl-3-methoxyphenyl) -3-hydroxymethyl-7-methoxy-5-benzofuran propanol (5), 2, 3- dihydro-2- (4' -β-D-glucopyranosyl-3' -methoxyphenyl) -3-hydoxymethyl-7-methoxy-5-benzofuran propanol (6), 2, 3-dihydro-2- (4' -β-D-glucopyranosyl-3' -methoxyphenyl) -3-hydoxymethyl-7-hydroxy-5-benzofuran propanol (7), 2, 3-dihydro-2- (4' -hydroxy-3' -methoxyphenyl) -3-hydroxymethyl-7-methoxy-5- 3-O-α-rhamnopyranosylpropan benzofuran (8), 2, 3-dihydro-2- (4' -hydroxy -3' -methoxyphenyl) -3- hydroxymethyl-7-hydroxy-5- (3-O-α-rhamnopyranosylpropan) benzofuran (9), and 1- (4-hydroxy-3-methoxyphenyl) -2- {2-hydroxy-4- (3-O-α-rhamnopyranosylpropan) phenoxy} propan-1, 3-diol (10). Compounds 1 and 3 were found to have no effect on the germination of lettuce. Compounds 110 were detected in the leaves of Hiba for the first time in this study.

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When a mixture of a few benzoins and a pyridine N-oxide- SbCl₅ (1 : 1) complex (Complex A) was boiled in nitromethane, the corresponding benzils were obtained in various yields dependent upon the kinds of substituents in each reactant. The yield of benzil becames higher by adding some tertiary amines. In this reaction, tribenzylamine is a good accelerator to promote it.
When Complex A, 4-picoline N-oxide-SbCl₅ (1 : 1) complex (Complex B) and 4-nitro-pyridine-SbCl₅ (1 : 1) complex (Complex C) were used as the oxidant of benzoin, the order of the reaction rate was as follows : Complex C>Complex A>Complex B
The oxidation of benzoin with these pyridine N-oxide - SbCl₅ (1 : 1) complexes seems to proceed according to the following there processes ; i) the oxidation by pyridine oxide-SbCl₅ (1 : 1) complexes themselves ii) the oxidation by α-OSbCl₄ pyridines and iii) the oxidation by the mixure of pyridine N-oxides and antimony (III) chloride.

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Structural studies on two ceramides (ceramide-I and ceramide- II) isolated from viscera of Euhadra hickonis, a Pulmonate, were carried out using fast atom bombardment mass spectrometry (FAB/MS), gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) and usual chemical methods. The major fatty acids of ceramide-I were hexadecanoic (19.6%) and 2-hydroxyhexadecanoic acids (14.3%), and that of ceramide- II was 2-hydroxyhexadecanoic acid (39.5%). The major long-chain bases of ceramide- I were 2-amino-16-methyl-4-octadecene-1, 3-diol (39.8%) and 2-amino-4- octadecene-1, 3-diol(19.6%), and that of ceramide-II was 2-amino-16-methyl-octadecane-1, 3, 4-triol (47.2%). The structures of the major molecular species of ceramide-I were found to be N-hexadecanoyl-2-amino-16-methyl-4-octadecene-1, 3-diol and N-2-hydroxyhexadecanoyl-2-amino-16-methyl-4-octadecene-1, 3-diol, and that of ceramide- II was N-2-hydroxyhexadecanoy1-2-amino-16-methyl-octade-ane-1, 3, 4-triol.
The most remarkable feature of the long-chain bases of ceramides in viscera of E. hickonis was the large amount of branched long-chain bases. To determine the pathway for the synthesis of sphingolipids in E. hickonis, the molecular species of ceramide-I and - II were compared with those of the ceramide moieties of ceramide monohexosides and sphingophosphonolipids.

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The solubilization of aromatic compounds (phenol, benzoic acid, benzene, ethylbenzene) in the aqueous solutions of didodecyldimethylammonium bromide (DDAB) vesicles was investigated as a function of temperature by measuring the solubilization equilibrium constants (K_vesicle), the microviscosity of the vesicle bilayer membrane, and the degree of the dissociation (α) of the counter-ion from the vesicle. Benzene and ethylbenzene are only sligthtly solubilized below the temperature of 8°C, and K_vesicle between the DDAB vesicle and the bulk aqueous phase shows an abrupt increase at the temperature range 810°C. The fluorescence measurement indicates that the phase transition temperature (Tc) of the DDAB vesicle is about 9.5°C. The solubilization of benzene and ethylbenzene will depend on the microviscosity of the vesicle bilayer membrane. The comparison of K_vesicle with the partition coefficient (K_dodecane) of the aromatic solute between the n-dodecane phase and the water phase suggests that the benzene molecule is solubilized at the vesicle surface where the π electron cloud of the benzene interacts with the changed surfactant head groups, and that the ethylbenzene molecule is located inside the bilayer membrane. On the other hand, K_vesicle values of phenol and benzoic acid exhibit a maxima at ca. Tc of DDAB, and the α value of the vesicle also has a maximum around Tc. It is thought that the solubilization of phenol and benzoic acid depends on the degree of the DDAB vesicle charge, and these polar solutes are located at the vesicle surface because the polar groups are attracted electrostatically to the charged head groups of DDAB.

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Autoxidative behavior of salmon egg oil, abundant in polyunsaturated phospho-lipid, was compared with that of euphausiid and salmon oils. Salmon egg and euphausiid oils were much more stable than salmon oil toward autoxidation at 30°C, since the former two oils contain phospholipid and astaxanthin, a carotenoid. The oxidative stability of salmon egg oil and its triacylglycerol and phospholipid fractions was assessed under the same conditions. Hydroperoxide accumulation in salmon egg oil was found to be somewhat more suppressed than in the case of the triacylglycerol or phospholipid fraction owing to the antioxidative effects of astaxanthin and tocopherol in salmon egg oil.
The autoxidation of lipid abundantly present in polyunsaturated fatty acids was suppressed by astaxanthin, tocopherol and phospholipid, and phospholipid acted as a synergist of tocopherol.

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Semiequilibrium dialysis measurements have been made to investigate the solubilization of benzene derivatives such as phenol, dimethylphthalate (DMP), benzoic acid (BA) in dodecyltrimethylammonium bromide micelles. Solubilizing capacity and solubilization equilibrium coefficients for phenol whose dissociation degree changes with increasing pH decrease with an increase in the pH of micellar solution, but those for DMP which is not dissociated in water are independent of pH of the micellar solution. Solubilizing capacity and solubilization equilibrium coefficients for BA are independent of pH in the region of pH=5.5-9.0 where BA almost dissociates in water.
It is found that solubilization of the benzene derivatives is strongly dependent on their dissociation degree and polar groups.

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New fluoroalkylated allyl-, diallyl- and diallyldimethyl-ammonium chloride oligomers with carbon-carbon bonds were prepared under very mild conditions by oligomerization of allyl ammonium chloride and cyclo-oligomerization of diallyl-or diallyldimethyl-ammonium chloride using fluoroalkanoyl peroxides. The co-oligomerization of fluoroalkanoyl peroxides with allylammonium chloride and co-monomers such as acrylic acid, 2- (methacryloxy) ethane sulfonic acid and trimethylvinylsilane afforded the corresponding fluoroalkylated allyl ammonium chloride co-oligomers under similar conditions. Fluoroalkylated allylammonium chloride homo-oligomers were soluble in water. The diallyl- and diallyldimethyl-ammonium chloride homo-oligomers and co-oligomers were soluble not only in water but polar organic solvents such as methanol, ethanol and dimethylsulfoxide, as well. These fluoroalkylated cationic homo- and co-oligomers were capable of reducing the surface tension of water to around 10 mNm^-1. They should thus prove useful as new allyl-type cationic oligo-surfactants containing fluoroalkyl groups. Fluoroalkylated allylammonium chloride oligomers were evaluated for activity against HIV-1 replication in MT-4 cells. Fluoroalkylated oligomers in some cases inhibited HIV-1-induced cytopathogenesis, but the growth of MT-4 cells was inhibited in all cases.

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Polyunsaturated monoacylglycerols (MGs) and triacylglycerols (TGs) were oxidized in aqueous micelles. GC analysis of decrease in unoxidized polyunsaturated fatty acyl (PUFA) component of MGs during oxidation indicated monodocosahexaenoin to be the most stable forward oxidation, followed by monoarachidonin, monolinolenin and monolinolein. The higher stability of docosahexaenoate than linoleate in aqueous micelles was also noted in the oxidation of TGs. A comparison of the stability of MG and TG indicated the latter to be more easily oxidized in aqueous micelles. The higher rates of intramolecular free radical chain reactions among PUFA components of TG molecule compared to intermolecular chain reaction among PUFA components of MG would be the reason for this.

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Determination was made of critical micelle concentrations (cmc) for three ho-mologs of perfluoroalkanesulfonate salts, C_nF_2n+1SO₃Li (n=4, 6, 8, 10), C_nF_2n+1SO₃Me₄N (n=4, 6, 8, 10), and C_nF_2n+1SO₃Et₄N (n=4, 6, 8) in aqueous solutions at 25°C, and the results are expressed in the form, log cmc=A+Bn. B values are -0.435-0.465, indicating cmc to decrease by 2.72.9 for each CF₂ group added to perfluoroalkyl chain. Due to the high Krafft points of sodium and potassium salts, the influence of counterions on cmc for C₆H₁₃SO₃^-M⁺ (M=Li, Na, K, Me₄N, and Et₄N) was examined at 65°C. It was found that cmc decreased in the order of Li> Na> K> Me₄N> Et₄N, and this order is discussed on the basis of ionic hydration of alkali metal ions and the hydrophobic interactions of quaternary ammonium ions with micelles.

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