The studies for what the Japan Oil Chemists' Society prize of 1998 was awarded to the author are sorted as follows :
1) Development of multi-type ammonium salt surface active agents which are expected to have excellent properties
2) Synthesis of crown ethers which have abilities to recognize alkali metal and alkaline earth metal ions and utilization of their functions
3) Synthesis of sugar-derived surface active agents and their utilization in separation and selective transport of sugars based on their ability in differentiation of the structure of sugars
4) Development of oxazoline ligands which can be derived from carboxylic acids and amino acids with ease and their utilization in asymmetric organic synthesis
5) others
In this review, items 14) are described.

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Features of amphiphiles in solution such as micellization, solubilization in micelle and dissociation were thermodynamically examined, with primary attention directed to the degrees of freedom from the Gibbs' phase rule. Molecular aggregates of amphiphiles or micelles are not a phase but chemical species from the standpoint of this freedom. The conventional Krafft point is not a phase transition temperature but the temperature at which monomer surfactant concentrations become high enough for the monomers to start aggregating into micelles. Solubilization of sparingly soluble organic substances into micelles may be understood by regarding a micelle as a chemical species. The dynamics of solubilization can be mathematically analyzed only when micelles are treated as such. Acidity constants of sparingly soluble organic acids like bile acids were accurately determined from aqueous solubility change with pH. The degrees of freedom were found essential for themodynamic considerations of amphiphilic solution systems.

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Dipotassium β-glycyrrhizinate (GK2), contained in “Kanzou” root, with two hydrophilic sugarparts and one hydrophobic triterpenoid part is a three-based acid used as an anti-allerugic and anti-inflammatory drug in pharmaceuticals and soaps. The physicochemical features and behavior of GK2 and derivatives (GK2s) have been but little studied. To use GK2s effectively, the physicochemical characteristics of GK2s, interactions with an artificial membrane model and catalytic activity toward nonionic ester surfantant (NES), a solubilizing agent, must be studied. GK2s characteristically form anionic micelles depending on pH and structure of the hydrophobic triterpenoid skeleton. GK2 micelles deliver certain cationic drugs into hydrophobic membranes, particularly so at less than pH 5.5. GK2s catalyze the hydrolysis of NES. Pharmaceutically undesirable acidic catalysis by GK2s is due to the presence of carboxy groups that are not protonated in its structure. The catalytic activity of GK2 was found completely inhibited by an equimolar amounts of cyclodextrins (CyDs) such as γ-CyD owing to the formation of host-guest complexes. Both GK2 and NES are formed in pharmaceuticals at the same time. The adsorption of GK2 at 340nm was found useful for determining the microenviroment of the enone chromophore of GK2s.

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Acrolein, an unpleasant and troublesome by-product of overheated organic matter, occurs as a ubiquitous pollutant in the enviroment, e.g., incomplete combustion of plastic materials, cigarette smoking, and overheating frying oils. In this review, the process of discovery that the most toxic aldehyde acrolein is not just a pollutant but also a lipid peroxidation product that could be ubiquitously generated in biological systems is introduced. During incubation with protein, acrolein preferentially reacted with lysine residues to generate the novel acrolein-lysine adduct, N^ε- (3-formyl-3, 4-dehydropiperidino) lysine (FDP-lysine). Acid hydrolysis of the adduct led to derivative detectable with amino acid analysis. During incubation of LDL with acrolein, lysine residues that had disappeared were partially recovered by FDP-lysine. The same derivative was detected in the oxidatively modified LDL with Cu²⁺. To confirm the presence of protein-bound acrolein in vivo, the monoclonal antibody (mAb5F6) against acrolein-modified protein was raised. The acrolein-lysine adduct, FDP-lysine, was found to be an epitope of the antibody. Enzyme-linked immunosorbent assay (ELISA) for measuring free acrolein indicated a considerable acrolein to be released from Cu²⁺-oxidized LDL. That (i) oxidative modification of low-density lipoprotein (LDL) with Cu²⁺ generated acrolein-LDL adducts and (ii), during long-term incubation of protein with glucose, ascorbate, or arachidonate in vitro, arachidonate was the only source of antigenic material suggest polyunsaturated fatty acids to possibly be sources of acrolein that cause the production of protein-bound acrolein. Immunohistochemical analysis of atherosclerotic lesions from a human aorta demonstrated antigenic materials recognized by mAb5F6 to actually be present in the lesions and this to clearly be related to macrophages.

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Pseudomonas cepacia lipase (PCL) catalyzed transesterification between tributyrylglycerol (1) and 2-alkanol (2) was studied at 30°C using various organic solvents. Log E (E : the enantiomeric ratio) showed a rough negative correlation with the solvent hydrophobicity (log P) and inverse of the dielectric constant (D) of the solvent except in the case of bulky solvents. Log E vs. log P and 10/D plots varied according to the structure [carbon number (CN)] of (2). E was minimal at CN=8 and 10 for (2). The initial rate constant (k/s^-1mg^-1) was measured for (R) - and (S) -2-octanols [(R) - and (S) - (2b)]. Log k showed a rough positive correlation with log P, but was essentially independent of D except for bulky solvents. The slope of log k vs. log P for (R) - (2b) was less than for (S) - (2b).
Enantioselectivity (E value) is thus shown to be affected by solvent and substrate (2) structures and solvent features. A plausible active site mode of PCL catalyzed transesterification was proposed and discussed.

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The quantification of chlorophyll (Chl) pigments such as pheophytins a and b (Pheo-a and -b), and pyropheophytins a and b (Pyro-a and -b) present in edible vegetable oils was conducted by high performance-liquid chromatography (HPLC) provided with a fluorescent detecter. A reversed phase ODS column in combination with a mixture of acetone, methanol and water (60 : 36 : 4, vol) as the mobile phase was found most effective for separating Chl pigments by HPLC. The pigments were detected at an excitation wavelength of 420nm and emission wavelength of 660nm. Subsequent to the neutralized rapeseed (canola) and soybean oils, Pheo-a and -b and Pyro-a and -b could be determined by this method at the mg/kg level. The present HPLC is thus shown quite effective for the quantification of Chl pigments in edible oils.

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Commercial fatty-acid-ester-type surfactants are usually mixtures of mono- and di- (or poly) esters and unreacted hydrophilic moieties such as polyethyeneglycol (PEG). Their phase behavior is influenced by by-products. The phase behavior of commercial decaoxyethylene glycol dodecanoate ester (C₁₁EO₁₀ (E)) in water and in water-oil systems was compared with that of commercial decaoxyethylene dodecyl ether (C₁₂EO₁₀). No liquid crystalline phase was formed at any concentration in the water/C₁₁EO₁₀ (E) system. The cloud temperature of C₁₁EO₁₀ (E) was found to be 46°C, this being for less than that of C₁₂EO₁₀, 89°C, although the average EO- chain length surfactant of these is the same. The phase behavior of C₁₁EO₁₀ (E) in water was not significantlly influenced by PEG in a dilute region. The low cloud temperature may essentially have been due to the presence of diester. HLB temperature in either surfactant system was basically the same on using, when m-xylene, decane, and cyclohexane as oils. The diester dissolved in the presence of oil, and HLB temperature increased in the C₁₁EO₁₀ (E) system when the surfactant aggregates contained much monoester. This explains why HLB temperature in either surfactant system was essentially the same.

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Synthesis and Insecticidal activity of ureas and amides with an bicyclic monoterpenyl derivatives was examined.
2-Carene (1), 3-carene (2), thujone (3) and d-menthol (4) were converted to secondary amines (5) (8) by hydroboration, Jones oxidation, oximation (N, N-dimethylhydrazonation, methylation and elimination reaction) or reduction with LiAlH₄. The secondary amine derivatives were condensed with six chlorides to obtain urea (5a) (8e) and amide compounds (5f) (8f).
Twenty-four monoterpene derivatives obtained were tested for insecticidal activity toward Tyrophagus putrescentiae (T. putrescentiae) and Dermatophagoides farinae (D. farinae).
On filter paper, compounds (5a), (5d), (5e) and (6b) (6d) from (1) and (2) showed higher insecticidal activity than N, N-diethyl-m-toluamide (DEET) for D. farinae. In air dusting for D. farinae, these compounds (5d) and (6b) (6d) at 0.2g/m² had exterminative effects for a long time, and were more active than DEET.

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Random and block copolymers of cyclic trimethylene carbonate (TMC) with lactone [ε-caprolactone (CL) or δ-valerolactone (VL)] were synthesized for the first time in this study using a weak cationic catalyst [AlEt₃/H₂O (1 : 0.75)]. Elimination of carbonic acid from TMC unit did not occur during (co) polymerization, thus making it possible to obtain high molecular weight carbonate (co) polymers in high yield, with no ether linkage in the main chains. Measurement of NMR and thermal properties of the polymers indicated that these copolymers could be prepared separately.
The degradability of (co) polymers by enzymes [lipoprotein lipase and cholesterol esterase (both from Pseudomonas sp.)] was examined and that of TMC/lactone copolymers was generally more extensive compared to the TMC (or lactone) homopolymer and the degradability of random copolymers was greater than that of block copolymers. The greater degradability of polymers by lipoprotein lipase than that by cholesterol esterase was particularly evident for TMC-rich block copolymers, suggesting substrate specificity of the lipase for TMC unit to exceed that of esterase.
Water-soluble products of TMC/CL (=17/83) random copolymer degraded by lipoprotein lipase were fractionated using HPLC and a fraction collector. The ¹H NMR spectra of the products indicated the TMC/CL copolymer to ultimately be degraded into 1, 3-propanediol and 6-hydroxycaproic acid.

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The methanolysis of n-butyric, lauric and myristic acids was found to be accelerated by monotonous compression and points of maxima were noted for the yields of methyl palmitate and methyl stearate. Effects at 0.4MPa to 200MPa were essentially the same for all fatty acids, though differed considerably for palmitic and stearic acids at higher pressures. In the case of palmitic and stearic acids, pressure corresponding to maximum yield was higher for lower acid concentrations. For mixed saturated fatty acids at 1200MPa and 70°C, methyl laurate was obtained in 66% yield while that of methyl stearate was only 1%.

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Using supercritical carbon dioxide, a method for extraction of safflower seed oil was established. The supercritical fluid extraction (SFE) apparatus was set up and the extraction conditions were made optimal to attain 100% oil recovery at pressure of 490 bar, a temperature of 70°C and a extraction time of 50min with multiple-batch extraction and addition of 300μL n-hexane as a modifier. By use of multiple-batch extraction the extraction efficiency of 35.3% comparing to 12.8% in a single-batch extraction was obtained. The present SFE method was found to lower the organic solvent consumption and the time required for the extraction.

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