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Durch die Einwirkung von phenacylbromiden auf 3-Amino-6-chlorpyridazin wurden verschiedenartige 2-Phenyl-6-chlorimidazo [1, 2-b] pyridazine hergestellt. Das Chloratom der letzteren wurde durch Einwirkung von Na-Alkoholaten, Dialkylaminen bzw. wasr. alkoholischem Kali gegen Alkoxyl-, Dialkylamino- bzw. Hydroxyl-gruppen ausgetaus ht.

N, N-Dialkyl 3-(substituted anilino) butyramides were prepared by condensing of N, N-dialkyl crotonamides or N, N-dialkyl 3-chlorobutyramides with substituted anilines. N, N-Dialkyl 3-(N'-benzyl-substituted anilino) butyramides were prepared from N, N-dialkyl 3-(substituted anilino) butyramides and benzyl chloride. Some of the compounds thus prepared have analgetic activities.

The methyl steroid-21-yl-β-D-glucopyranosiduronates were prepared by treatment of Reichstein's compound S, cortisone, hydrocortisone, prednisone and prednisolone with methyl 1-bromo-1-deoxy-2, 3, 4-tri-O-acetyl-α-D-glucopyranosiduronate. Treatment of these compounds with methanolic ammonia afforded the corresponding steroid-21-yl-β-D-glucopyranosiduronamide.

The oxidation of N, C-protected L-2, 4-diaminobutyric acid, L-ornithine and L-lysine with RuO4 gave the corresponding L-asparagine, L-glutamine and L-2-aminoadipic acid 6-amide derivatives, respectively.

Treatment of 1,3-dialkyl-7-azalumazine derivatives with alcoholic sodium hydroxide caused a benzylic acid type rearrangement followed by decarboxylation and oxidation by air to give the corresponding 5,7-dialkyl-5H-imidazo[4,5-e]-as-triazin-6-(7H)ones (7,9-dialkyl-6-azapurin-8-ones).

Synthese a partir de benzhydryl-1 azetidinone-3 par l'intermediaire d'alcoxycarbonyl-1 tosyloxyimino-3 azetidines

The reaction of primary alkyl esters of phosphorus oxyacids with p-toluenesulfonic acid (TsOH) in refluxing solvents gave the correspondinf p-toluenesulfonates (TsOR). We found that the secondary alkyl esters reacted with TsOH at lower temperature (r.t.-40°C) to afford TsORs in good yields. It is suggested that sulfonic acids may be useful for the selective dealkylation of mixed esters.

Treatment of isoalloxazine 5-oxides with acetic anhydride yielded the corresponding 8-acetoxyisoalloxazines exclusively, which are labile to hydrolysis to give 8-hydroxyisoalloxazines (8-hydroxyflavins).

The ruthenium tetroxide (RuO4) oxidation of N-acylated L-proline esters, prepared from L-proline, was carried out under two-phase conditions to afford good yields of the corresponding lactams with no appreciable racemization, and the products were hydrolyzed in aqueous hydrochloric acid to L-glutamic acid. Similar transformation starting with recemic 2-piperidinecarboxylic acid and 2-azetidinecarboxylic acid gave 2-aminoadipic acid and aspartic acid, respectively. A novel chemical conversion of cyclic α-amino acids into α-aminodicarboxylic acids has been accomplished. A new solvent system, ethyl acetate-water, was developed for this two-phase oxidation. It was found to be very useful in reducing the necessary reaction time.

Ruthenium tetroxide (RuO4) oxidation of N-alkyllactams proceeded regioselectively depending on the size of lactam ring, except for the seven-membered ring. Four- and eight-membered N-methyl- and N-ethyllactams were oxidized at the exocyclic α-carbon adjacent to nitrogen to produce the N-acyllactams and NH-lactams, while five- and six-membered lactams underwent endocyclic oxidation to yield the cyclic imides. Oxidation of seven-membered lactams yielded a mixture of products arising from both exocyclic and endocyclic oxidations. These regioselectivities were confirmed in the oxidation of substrates having a tertiary carbon at the oxidation position.

Reaction d'esters alkyliques d'acides carboxyliques, de carbonates de dialkyle avec l'acide p-toluene-sulfonique dans le toluene ou le benzene

A simple synthetic method for the preparation of amides from the corresponding primary alkylamines was elaborated using ruthenium tetroxide (RuO4) oxidation as a key step.

The oxidation of N, C-protected L-2, 4-diaminobutyric acid, L-ornithine and L-lysine with RuO4 gave the corresponding L-asparagine, L-glutamine and L-2-aminoadipic acid 6-amide derivatives, respectively.

Recently, it has been reported that the treatment of amino acids with alkyl p-toluenesulfonates in alcohol affords the p-toluenesulfonates of the corresponding alkyl esters in high yields. The results of our examination of this reaction indicated that the reaction proceeds predominantly through the general acid-catalyzed esterification of carboxylic acid by alcohol, and the involvement of transesterification is minor.

Phenomenology and phenomenological philosophy have been well received in the academic world and by intellectuals, since the introduction of Husserl’s Logische Untersuchungen. Beginning with the Meiji Restoration, Japan quickly absorbed not only science and technology from the West, but also the economic system, the social structure, the legal and political organization, as well as art, literature, and philosophy. And it was thus natural that the introduction of phenomenology and phenomenological philosophy would be similarly appreciated.

In his later work, The Crises of European Sciences and the Transcendental Phenomenology, Husserl designates the indivisible bond among science, life, and philosophy as the conceptual unity of the intellectual culture of modern Europe. According to Husserl, the crisis of European culture and science is rooted in the dissolution of this conceptual unity. Therefore, this crisis can be overcome only if the authentic bond of these three moments is reestablished; and to Husserl, this is precisely the task of transcendental phenomenology.

Ruthenium tetroxide oxidation of N, C-protected derivatives of L-2, 4-diaminobutyric acid, L-ornithine and L-lysine was carried out under two-phase conditions and the corresponding imides, formed through the oxidation of the methylene adjacent to the ω-amino group, were obtained in good yields. Removal of the protecting groups from the products gave L-asparagine, L-glutamine and L-2-aminoadipic acid 6-amide, respectively. Thus, the first chemical conversion of L-α, ω-diamino acids into the corresponding L-ω-carbamoyl-α-amino acids without racemization has been established. L-2-Aminoadipic acid 6-amide was further converted to L-2-aminoadipic acid by acid hydrolysis. This represents a convenient method for the synthesis of L-2-aminoadipic acid starting from L-lysine.

Treatment of ethyl acetoacetate with anhydrous p-toluenesulfonic acid at room temperature led to ethyl isodehydroacetate (1) in high yield by acid-catalyzed condensation. On the other hand, in refluxing toluene, the unexpected ethyl ester of p-toluene-sulfonic acid (2) was formed in moderate yield. This constitutes a new direct esterification of arenesulfonic acids.

The utility of four urethane type N-protecting groups, benzyloxycarbonyl (Z), p-nitro-benzyloxycarbonyl [Z(NO2)], trichloroethoxycarboyl (Troc) and tert-butoxycarbonyl (Boc) groups, was tested in the ruthenium tetroxide (RuO4) oxidation of N-protected L-proline esters. Three groups, but not the Z group, which was decomposed by RuO4, were found to be stable during the oxidation and afforded high yields of the corresponding L-pyroglutamic acid esters. Removal of the protecting groups from the oxidation products was carried out successfully in the usual manner to give N-unsubstituted (NH-type) L-pyroglutamic acid derivatives without racemization. The first transformation of L-proline into L-pyroglutamic acid and its derivatives has been accomplished.