Several crystalline β-D-glycopyranosyl N, N-dialkyldithiocarbamates (sugar=gluco, galacto, xylo or lacto ; alkyl=methyl or ethyl) were synthesized by reaction of sodium N, N-dialkyl-dithiocarbamates with acetylated α-D-glycopyranosyl bromides and sequential deacetylation with methanolic ammonia or sodium methoxide in methanol. Although the glycosyl dithiocarbamates were stable against chilled alkalis and which is a marked difference from glycosyl xanthates or isothiuronium, easily decomposed with mercury salts to form glycosides under the presence of alcohols or phenols. D-Glucopyranosyl N, N-diethyldithiocarbamates having N, N-diethyldithiocarbamoyl radical [chemical formula] at C6 in acetylated D-glucoses or methyl D-glucopyranosides, along with the didithiocarbamate having two carbamoyls at C1 and C6 in acetylated D-glucopyranose, were also synthesized. Reflux of methyl β-D-glucopyranoside-6-deoxy-6-N, N-diethyldithiocarbamate with sodium methoxide in methanol afforded methyl 6-deoxy-6-thio-β-D-glucopyranoside, isolated as its tetraacetate. The method presented a novel synthetic way of thiosugars.

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Swertisin, C₂₂H₂₂O₁₀, m.p. 243°(decomp.), was isolated in a pure state from the whole herb of Swertia japonica MAKINO (Gentianaceae), and identified as 6-C-β-D-glucopyranosylgenkwanin. Isoswertisin, C₂₂H₂₂O₁₀, m.p. 295°(decomp.), was obtained by the acid-treatment of swertisin, and formulated as 8-C-β-D-glucopyransylgenkwanin. At the same time, it was found that they were interconvertible into each other, reminiscent of the interrelationship between vitexin and isovitexin.

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Synthesis of the decapeptide, histidylphenylalanylarginyltryptophylglycylserylprolylprolyl-lysylaspartic acid (I) corresponding to the C-terminal portion of β-melanocyte-stimulating hormones (β-MSH) from pig, sheep, beef, monkey and human was described. I was obtained by deformylation of histidylphenylalanylarginyltryptophylglycylserylprolylprolyl -N^ε- formyllysylaspartic acid (II) with aqueous hydrazine. The MSH activity of I and II was examined in vitro. It was found that I and II exhibited the activity, 2.4×10⁶ and 1.0×10⁶ MSH U/g. respectively.

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87 groups of tablets were made using 3 sieved fractions of aspirin and potato or corn starch varying formulation and compressional force. Disintegration of the tablet was investigated in detail by the thermal analysis reported previously. The relation between porous structure of tablet and disintegration was studied and the following conclusions were drawn from the results obtained. 1. The rate-determining step of the disintegration was the penetration of water into the porous structure of a tablet. 2. It was confirmed that starch can develop the capillary structure in aspirin tablet. This effect was observed when aspirin particles larger than starch grains were mixed with starch. The effect seemed to be larger at corn starch than potato starch. 3. There should be the critical amount of starch necessary for the disintegration depending upon the particle size or the specific surface area of ingredients. The smaller the particle size of aspirin, the more amount of starch was required for the tablet disintegration. The tablet of the smallest aspirin (11.9 μ in mean particle size) did not disintegrate by the addition of 20% of starch. 4. In the case of the tablets that disintegrated very rapidly and completely, the wall of the capillaries in the tablets was considered as starch. This may be the reason why the tablet with potato starch disintegraties more rapidly than with corn starch. 5. The model proposed for disintegration well explained why the tablet made from the medium aspirin particle (294 μ in mean volume-surface particle diameter) disintegrated more rapidly than that containing the largest aspirin (953 μ).

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Thioxo-thioenol tautomerism was discussed in ethyl β-mercaptothiocinnamate and β-mercaptocinnamamides, in connection with their chelating abilities, through the ultraviolet absorption spectra in various solvents, and the estimation of the thioenol by the iodometry. Ethylβ-mercaptothiocinnamate and N-phenyl-β-mercaptocinnamamide were confirmed to be present mainly as the cis-thioenol form, and the equilibrium should be considered only between th thioxo and the cis-thioenol forms. On the contrary, in N-ethyl-β-mercaptocinnamamide, the trans-thioenol form should be taken into consideration in its thioxothioenol tautomerism.

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The accumulative uptake of S-benzoylthiamme (SBT) by human red cells was demonstrated and the detail of the transport mechanism was investigated. From the studies on i) the transport of SBT into the red cells and into the ghosts, ii) the decomposition of SBT in the red cell homogenate and in an aqueous medium, iii) the effect of the concentration gradient on the uptake, and iv) the effect of the extracellular pH on the uptake, it was concluded that the penetration of SBT into the red cells proceeds through two steps ; the first, a passive diffusion of SBT through the cell membrane, and the second, a rapid decomposition of SBT to undiffusible thiamine and the resultant its accumulation in the cell. In a series of substituted S-benzoylthiamines, the rate of their decomposition to thiamine in the red cell was found to be a predominant factor determining the rate of the penetration into the red cells, both being a linear function to Hammett's σ-constants of the substituents. An important role of SBT in the intestinal absorption of S-benzoylthiamine monophosphate and the followed high blood thiamine concentration and its duration was pointed out.

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Pachysamine-A and B- are minor alkaloids of Pachysandra terminalis SIEB, et ZUCC., a Buxaceous plant. The structures of both alkaloids were discussed herewith and assigned to the formulas III and VIII, respectively.

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Structure determination of epipachysamine-A(I), -B(VIIIa), -C(III), -D(VIIIb), -E(VIIIc), and -F(V), new alkaloids isolated from Pachysandra terminalis SIEB. et ZUCC. (Buxaceae), was described herewith. Among these alkaloids, epipachysamine-B(VIIIa) is unique in that it has a nicotinamide grouping in the molecule.

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Structure of terminaline, one of minor alkaloids isolated from the strongly basic alkaloid fraction of Pachysandra terminalis SIEB. at ZUCC. (Buxaceae), was investigated and the complete structure (Ia) including absolute configuration was proposed for the alkaloid.

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Kessane, the sesquiterpenoid oxide isolated from Japanese valerians, has been elucidated to have the stereostructure I on the basis of its spectroscopic and chemical studies and derivation from 2-epi-α-kessyl alcohol (VI;R=H). On Huang-Minlon reduction both α-kessyl ketone semicarbazone (V;R=NNHCONH₂) and isokessyl ketone (VII) have been found to give the same product which is considered to be a mixture of kessane (I) and isokessane (II).

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The sesqutierpenoid alcohols, kessanol and 8-epi-kessanol, isolated from certain kinds of Japanese valerian, have been shown to be 2-deoxykessyl glycol (I;R=H) and 2-deoxy-8-epi-kessyl glycol (III;R=H), respectively, by physicochemical studies of the alcohols and their oxidation products, kessan-8-one(II). The mixture of the wwo alcohols (I and III;R=H) has been synthesized from kessyl glycol (IV;R=H, R'=H). The configuration of the hydroxyl at C-8 as being α in kessanol and β in 8-epi-kessanol has been confirmed by application of the dissymmetry rule.

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Proton magnetic resonance spectra of substituted ammonium ions were studied in deuterium oxide, being classified in methylammonium, ethylammonium, β-substituted ethylammonium, and vinylammonium ions. The chemical shifts of the methyl groups are discussed in terms of inductive effects of other substituents on nitrogen atoms. From the internal chemical shifts of ethyl groups, the electronegativity of (Alkyl)₃N⁺ were derived to be 3.16 according to Cavanaugh and Dailey's equation. Spin-coupling constants between ¹⁴N and protons were usually observed in the cases where the electric field at the ¹⁴N nucleus is thought to be homogeneous. We suggest that the sign of J_14N-C-CH3 in ethyltrialkylammonium ions might be positive. Interestingly, spin-couplings between ¹⁴N and the vinyl protons in trimethyl-vinylammonium bromide were evidently observed even at room temperature.

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The synthesis of optically active hexahydro-1H-pyrrolizin-1-one(I)from L-proline and the resolution of hexahydro-1(5H)-indolizinone(II), hexahydro-8(5H)-indolizinone(III), and hexahydro-2H-quinolizin-1(6H)-one(IV) by means of d-3-bromo-8-camphorsulfonic acid and d-10-camphorsulfonic acid were described. Their rate constants and half-times for racemization were determined under various conditions, at 20°, and in aqueous ethanol I was found to be racemized very rapidly, while in hydrochloric acid, no racemization was observed.

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