Inosine 5′-phosphate has been synthesized by heating isopropylidene-inosine with mono (or di)(tri-n-butylammonium)-, mono (triethylammonium)-, or monoanilinium phosphate in dimethylformamide followed by removal of the protecting group. Similarly, from isopropylidene-adenosine, -guanosine, -cytidine and -uridine, the corresponding 5′-nucleotides were obtained and rom thymidine, its mono- and di-phosphate. Furthermore, inosine 5′-phosphate and 5′-diphosphate were prepared by heating isopropylidene inosine with tri-n-butylammonium-pyrophosphate or -polyphosphate.

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Reactions of 4-amino-3, 6-dichloropyridazine (I) with caustic alkali in methanol and of 4-amino-3, 6-dimethoxypyridazine (III) with acetylsulfanilchloride in pyridine were studied. In the former reaction, the reaction sequence to the formation of (III), 4-amino-6-chloro-(IV) and 4-amino-6-methoxy-3(2H) pyridazinone (V) was clarified. In the latter condensation reaction, it was found by thin-layer chromatography that 2-p-acetylaminobenzenesulfonyl-5-amino-6-methoxy-3(2H) pyridazinone (XI), two demethylated compounds (IX and X) of N¹-(3, 6-dimethoxy-4-pyridazinyl)-N⁴-acetylsulfanilamide (VIII) as well as the main product (VIII) were produced and their structures were proved. The demethylation reactions of VIII and its deacetylated compound (XII) with pyridine hydrochloride were examined.

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Reactions of 4-amino-6-methoxy-(I), 4-amino-3 (2H) pyridazinone (II) and 3-methoxy-4-amino-6 (1H) pyridazinone (VIII) with tosyl chloride in pyridine were investigated. 4-Amino-3, 6-dimethoxypyridazine (XV) was also allowed to react with tosyl chloride in pyridine andN¹-(3, 6-dimethoxy-4-pyridazinyl-(XVI), N¹-(3-oxo-6-methoxy-2, 3-dihydro-5-pyridazinyl)-p-toluenesulfonamide (XVI-) and 2Ip-toluenesulfonyl-5-amino-6-methoxy-3 (2H) pyridazinone (X) were isolated. Consideration was made on the mechanism of the formation of X.

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Five kinds of N¹-(2-methyl-3-oxo-2, 3-dihydro-4(or 5)-pyridazinyl) sulfanilamides were prepared starting from chloromaleic anhydride. In addition, three kinds of N¹-(2-methyl (or phenyl)-3-oxo-2, 3-dihydro-4 (or 5)-pyridazinyl) sulfanilamides were also prepared. It is of interest that of these sulfonamides prepared, those substituted with the sulfanilamide group at 4-position of pyridazine nucleus have shown marked activities in vitro.

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4-Amino-3 (2H) pyridazinone derivatives (Ia∼Id) were methylated with dimethyl sulfate in aqueous sodium hydroxide solution, yielding 2-methyl compounds (IIa∼IId) and zwitterionic 1-methyl compounds (IIIa∼IIId). The position of the methyl group of these products (II and III) was unambiguously determined. The ratio of formation of both II and III in the methylation has been found to be markedly influenced by the substituent at adjacent 6-position.

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Dehydration of 5α-hydroxy-6β-thiocyanato-5α-pregnane-3, 20-dione with hydrochloric acid and with sodium methoxide, respectively, was studied. The former reagent gave 6α-thiocyanatoprogesterone and 2-chloro-2-thiazolino compound, whilst sodium methoxide yields 6α-hydroxyprogesterone.

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As previously reported, three rearrangement products were obtained on irradiation of quinaldine 1-oxide in methanol solution. To investigate the scope and further clarification of the mechanism of this rearrangement, the reaction has been extended to a variety of substituted azanaphthalene N-oxides and some phenanthridine N-oxides. The results obtained seem to support the postulated mechanism, namely, the photochemical formation of a three-membered ring intermediate (such as IV in the case of quinoline 1-oxides) and its subsequent thermal rearrangement to the final products.

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Skimmianine isolated from Skimmia plants fed with anthranilic acid (T), acetate (1-¹⁴C), acetate (2-¹⁴C) and DL-tryptophan (3-¹⁴C) was shown to be radioactive. Degradation of the labeled skimmianine showed that the radioactivity was located in the benzene ring when anthranilic acid (T) was administered, while it was located at the position 3 of quinoline nucleus when acetate (2-¹⁴C) or DL-tryptophan (3-¹⁴C) was used as the labeled precursors. On the basis of these results, a scheme of the biosythesis of skimmianine was proposed in which skimmianine was shown to be derived from anthranilic acid and acetate.

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Conformations of four 3, 6-disubstituted derivatives of methyl α-D-altropyranoside in various solvents were studied by nuclear magnetic resonance spectroscopy. The derivatives examined included methyl 3, 6-diamino-3, 6-dideoxy-α-D-altropyranoside (I), its di-N-acetate (II), tetar-O, N-acetate (III) and methyl 3, 6-diazido-3, 6-dideoxy-α-D-altropyranoside (IV). Analysis of the spectra revealed that the predominant conformation in all the cases was C1, but I and II in deuterium oxide were shown to exist partly in the 1C conformation. IV in deuteriochloroform existed probably in a mixture of three conformers. Infrared spectroscopy indicated that the conformers of IV in inert solvents existed in the intramolecularly hydrogen bonded forms. The resonance data of methyl 6-azido-6-deoxy-2-O-methanesulfonyl-α-D-glucopyranoside (X) and methyl 2, 6-di-O-methanesulfonyl-α-D-glucopyranoside (XI) were added.

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Synthesis of tri- and tetra-iodoallene (III and IV) from 3-bromo-1-propyne (I) was described. III and IV are very susceptible to autoxidation and both the autoxidation and a solvolysis occurred in aqueous tetrahydrofuran or alcohols to afford the following products depending on the solvents. The reaction of III in aqueous tetrahydrofuran gave triiodoacrdein (XVI) and cis-2, 3-diiodoacrylic acid (XVa). The reaction of III in methanol gave XVI and methyl cis-2, 3-diiodoacrylate (XVb). The reaction of IV in aqueous tetrahydrofuran, methanol, or ethanol gave triiodoacrylic acid (XIIIa), methyl triiodoacrylate (XIIIb) or ethyl triiodoacrylate (XIIIc), respectively. The formation of III from 1, 3-diiodopropyne (II) by the action of alkali was well explained in terms of intermediate formation of the allenic carbanion (IX) followed by the iodination of IX with the hypoiodite resulted from the ethynyl iodine of III. A reaction mechanism involving the intermediate formation of the epoxides (XXIII) and their isomerization to the corresponding carbonyl compounds with the 1, 2-iodide shift gave a good explanation proposed for the oxygenolytic solvolysis of III and IV.

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Odoroside H (Ia) was converted into 14β, 15β-epoxy-5β-card-20(22)-enolide-3β-ol-β-D-monodigitaloside (IIIa) in the following reaction sequence : Dehydration of odoroside H diacetate (Ib) with thionyl chloride in pyridine to give 14-anhydrodigitoxigenin-monodigitaloside diacetate (IIc). Mild hydrolysis of IIc with acid afforded the corresponding acetyl-free glycoside (IIa) together with monoacetate (IIb). These 14-anhydro compounds (IIa, IIb and IIc) were treated with N-bromoacetamide followed by alumina chromatography to yield 14β, 15β-epoxy-5β-card-20(22)-enolide-3β-ol-β-D-monodigitaloside (IIIa), and its mono- and diacetate (IIIb and IIIc) respectively. Microbiological deacetylation of IIIc furnished IIIa. In the same manner, digitoxin tetraacetate (VI) was changed into 14β, 15β-epoxy-5β-card-20(22)-enolide-3β-ol-β-D-tridigitoxoside (VIIIa).

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The absolute configuration of (+)-α-methylphenylalanine hydrochloride has been elucidated to be either R- or d-configuration by the chemical correlation with (-)-α-methylaspartic acid, whose absolute configuration had been cofirmed to be R-configuration. The resolution of N-acetyl-DL-α-methylphenylalanine through its menthyl esters was also reported.

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In der Fortsetzung des Versuchs zur Ableitung von Derivaten des Octahydroindolochinolizins aus Chinolin hat der Verfasser nun trans-9-Methoxy-1, 2, 3, 4, 6, 7, 12, 12b-octahydroindolo [2, 3-a] chinolizin (Xa) und trans-10-Methoxy-1, 2, 3, 4, 6, 7, 12, 12b-octahydroindolo [2, 3-a] chinolizin (Xb) aus dem entsprechenden Methoxyderivat des 4-Chlorchinolins hergestellt.

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The stereochemical correlation of dihydroprotopanaxadiol (V) with dammaranediol-I (VI) has been established. It has concluded that protopanaxadiol and panaxadiol should have C/D trans 17β-H configuration and can be formulated as I and II respectively.

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It has been proved that the prosapogenin obtained from ginsenosides-Rb₁, -Rb₂, and -Rc (ginseng saponins) by the partial hydrolysis with hot aqueous acetic acid is formulated as II.

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The reaction between ethyl ο-nitro-hydroxy-3-coumarincarboxylates (I, VI, and XI) with zinc powder in acetic acid, acetic anhydride, or a mixture of acetic acid and acetic anhydride were examined. The reaction of the ο-nitro-hydroxy compounds in acetic acid gave ethyl ο-amino-hydroxy-3-coumarincarboxylates (II, VII, and XII) and in a mixture of acetic acid and acetic anhydride yielded ethyl ο-acetamido-hydroxy-3-coumarincarboxylates (III, VIII, and XIII). The amino and acetamido compounds were refluxed with acetic anhydride to obtain ethyl ο-dicaetylamino-acetoxy-3-coumarincarboxylate (IV, IX, and XIV). The acetamido compounds obtained were fused with phosphorous pentoxide to yield new ethyl pyranobenzoxazolecarboxylates (V, X, and XV).

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N-Substituted-2-methyl-7-oxo-7H-pyrano [3, 2-e] -, -6-oxo-6H-pyrano [2, 3-f]- and -8-oxo-8H-pyrano [3, 2-g]-benzoxazole-8-, -7-and-7-carboxamide were prepared by fusing ethyl pyranobenzoxazolecarboxylate series with primary amines, separately. Aniline, 2-aminopyrimidine, 6-amino-2, 4-dimethylpyrimidine, 2-aminopyridine, and 2-amino-5-bromopyrimidine were used for the fusing reaction as primary amines.

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UV-irradiation of quinoline 1-oxide derivatives were studied by electron spin resonance technique and 4-nitroquinoline 1-oxide (4-NQO) derivatives except for 3-methyl-4-NQO and 4, 8-dinitroquinoline 1-oxide were found to produce two kinds of stable radicals in dioxane or in benzene. This photochemical behavior was discussed from a view point of radical formation.

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