A comvenient method for the preparation of N-acyl O-TMS derivatives of sphingolipid bases is described; i.e., O-TMS derivatives of the bases, which are obtained by the HMDS+TMCS / pyridine treatment, are reacted with acid anhydride to give the desired N-acyl-O-TMS compounds.
The reaction of these bases with BSA/acetonitrile gave N, O-TMS derivatives which did not react with acid anhydrides, since the amino group was protected by the TMS group.
The above method was applied to several bases and the structures of the resulting products were determined by GLC and GLC-MS. N-Acyl O-TMS derivatives of synthetic C_n-dihydroshingosines were prepared by the present method. The erythro/threo ratios of their derivatives were the same as those determined using BSA. The present method can be easily carried out in a very short period of time. MS analyses for both O-TMS and N-acyl O-TMS derivatives are possible without having to prepare the N-acyl derivatives of sphingosine bases.

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Chemiluminescence from α-tocotrienyl acetate (I), α-tocopheryl acetate (II), and α-tocotrienol (III) oxidation were measured under an O₂ flow in the dark. At 60°C, no emission was observed from I. At 100°C, however, I chemiluminesced but not II and E. This suggests I to be rather stable at 60°C but its unsaturated side chain to be oxidized at 100°C. Also, it is possible that an interaction ocurs between the unsaturated side chain and the phenolic hydroxyl group of III.

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In determining the mechanism by which silicone oil (SO) suppresses the thermal deterioration of a frying oil, the influence of SO on the convection of soybean oil was examined. In this experiment, two kinds of SO were used : dimethyl polysiloxane (SO-DMPS) which very effectively suppresses the thermal deterioration of frying oils and methyl phenyl polysiloxane (SO-Phenyl-S) which has no such effect.
To observe the degree of convection, the following method was used. One drop of soybean oil colored with Sudan III was added to soybean oil with or without SO heated at 150°C, 180°C and 210°C.The life span of this pigment, i.e. the time between its addition and disappearance, was measured.
This pigment existed in oil with SO-DMPS for a longer period of time than in oil without SO. The time in oil with SO-Phenyl-S was the same as that in oil without SO.
These observations demonstrate that SO effectively slowed down the convection current of frying oil. The influence of SO on convection current of frying oil seems to be a function of SO.

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Radical telomerization was carried out using vinylpyrrolidon and methyl acrylate as monomers and 1-dodecanthiol. Benzene was used as the solvent and α, α'-azobisisobutyronitrile, as the initiator. The synthesized telomers (Ls-VPr-MA series) were treated with alkaline solvent to give various saponificated products. The cmc and chelating values of these telomers increased and lime soap dispersion power, orange OT solubilization and anti-redeposition ability decreased inversely with the degree of saponification. Surface tension and CaCO₃ dispersion ability attained a maximum at 50 mol% saponification.
The detergency of the detergent made from Ls-VPr-MA series telomers, builders and LAS or soap decreased as the degree of saponification increased. This tendency was particularly pronounced for the soap detergent system and polyester test fabric. In regard to the effects of the functional group of the telomers on detergency, the pyrrolidone and methoxycarbonyl group combination was considered far superior to individual carboxyl, carbamoyl, and pyrrolidone groups or their combination. The Ls-VPr-MA-Na telomers showed the strongest detergency effect at the degree of polimerization (DP) 10.
Detergency of the soap containing Ls-VPr-MA telomers was superior to the commercial lime soap dispersion agent, and Ls-VPr-MA telomers was effective when present at 5, 10% in the detergent.

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Changes in the effects of linear alkylbenzenesulfonate (LAS) on the growth of sporelings of Porphyra yezoensis were studied during biodegradation in sea water to determine its compatibility with aquatic organisms. The bioassay results showed inhibition by commercial LAS of the growth of sporelings to decrease on biodegradation in sea water and the longer alkyl chain homologues and outer phenyl isomers of LAS to effect the degree of toxicity toward sporeling growth.
The results of the chemical analysis by GLC showed the toxic components in commercial LAS to decrease more rapidly than other components during biodegradation in sea water. The toxicity of commercial LAS toward aquatic organisms in sea water is considered to decrease when its effective components undergo biodegradation

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Poly [(sodium acrylate) -co- (sodium vinyl sulfonate)] P (A-VS) with a no.-av. molecular weight (M_n) of 380026850 and poly (sodium vinylsulfonate) (PVS) with a M_n of 5040 were prepared and their detergency building powers were examined. Their sequestering power for Ca²⁺ and dispersing power for MnO₂ were determined and compared with the corresponding properties for oligomeric poly (sodium acrylate), tripolyphosphate (STPP) and disodium 3-oxapentanedioate (ODA). The biodegra clability of the oligomers was also studied under aerobic conditions.
Oligomeric P (A-VS) showed better detergency building performance than that of ODA, but was slightly inferior to those of STPP and oligomeric poly (sodium acrylate). Oligomeric P (A-VS) was more biodegradable than the corresponding sodium acrylate oligomer. Introduction of sulfonate groups to sodium acrylate oligomers promoted their biodegradability.

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