Treatment of dihydrolycorine (I) with phosphoryl chloride under mild conditions yielded a chlorohydrin (V). Reduction of this hydrin with zinc in acetic acid followed by reduction with hydrogen and platinum oxide afforded (-)-α-lycorane (VII), the steric structure of which was considered, in view of the sequence of reactions used in this transformation, to be that of the ring-system of dihydrolycorine.

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Chinin-1'-oxid bzw. Dihydrochinin-1'-oxid ergibt bei der Reissert'schen Reaktion das entsprechende 2'-Cyano-9-O-benzoylderivat des Chinins bzw. Dihydrochinins. Die modifizierte Reissert'sche Reaktion des Dihydrochinin-1'-oxides mit Silbercyanid und Benzoylchlorid in einer Chloroform-Losung ergibt ebenfalls das 2'-Cyano-9-O-benzoyldihydrochinin. Zur Konstitutionsbestimmung des letzerten und zur Kontroll der Reaktion wurde 6-Methoxychinolin-1-oxid der modifizierten Reissert'schen Reaktion unterworfen und 2-Cyano-6-methoxychinolin mit guter Ausbeute erhalten. 2'-Methoxycarbonyl- und 2'-Athoxycarbonyl-derivate des Dihydrochinins wurden hergestellt.

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Berberine inhibits the tyrosine decarboxylase activity of Streptococcus faecalis if the enzyme preparation is preincubated with the alkaloid under slightly alkaline conditions prior to initiation of the enzyme reaction at its optimum pH(5.5). When the preincubation is carried out at acidic pH, berberine causes no inhibition. At the pH range from 7.0 to 7.4 the enzyme can be protected from the inhibitory action of berberine by conducting the preincubation in the presence of a large amount of pyridoxal phosphate. This fact suggests that berberine competes with pyridoxal phosphate for the apoenzyme at least at this pH range. At pH 8.0, however, no protection can be observed even if the preincubation mixture contains an excess of pyridoxal phosphate, the reason for which is as yet to be explored. The possibility that the competition between berberine and pyridoxal phosphate is, at least partly, responsible for the bacteriostatic action of the alkaloid is discussed.

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It was found that berberine inhibits the tryptophanase system of Escherichia coli by competing with the coenzyme, pyridoxal phosphate, when acetone-dried cells or partially purified cell-free extracts were used as the enzyme. The inhibition was also found to be of irreversible nature. A mechanism was proposed to account for both the competitive and irreversible nature of the inhibition. Some kinetic considerations were made on the proposed mechanism. The inhibition of tryptophanase by berberine in intact cells was stronger than that in acetone-dried cells and it was inferred that different mechanisms are functioning in the inhibitions of the two types of cells.

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The alkaline degradation of methylhexabital J. P. (hexobarbital I. P.) in ethanol-water and methanol-water mixtures was carried out and the following results and conclusions were obtained. 1) The change of reaction rate was tested by simplified Scatchard's equation (1). In both mixtures, relationship between logarithm of reaction rate at zero ionic strength and reciprocal of dielectric constant was negatively linear down to a dielectric constant of 55 to 50. The values of γ, distance of approach sufficient for the reaction, were 1.2 Å and 0.90 Å in ethanol-water and methanol-water mixtures, respectively. The order of the magnitude of these values is not out of theoretical requirements. 2) Activation energies of the reaction in ethanol-water mixtures were found to be 16, 900 and 17, 100 cal./mole at the dielectric constant of 65 and 60, respectively. In methanol-water mixtures, they were 20, 600 and 24, 500 cal./mole at the dielectric constant of 65 and 55, respectively. It was found that activation energy increases as the dielectric constant decreases, in both mixtures. 3) From these observations, it may be concluded that the stabilization of a barbiturate in solution by addition of ethanol or methanol is attributable to the decrease of dielectric constant of the medium.

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Subsequent to the previous work, the stabilizing effect of polyhydric alcohols and sugars on the alkaline degradation of methylhexabital J. P. (hexobarbital I. P.) was studied with respect to dielectric constant of the medium and following conclusions were drawn : 1) The magnitude of retardation of the reaction rate by ethylene glycol and glycerol was as large as or slightly larger than that by alcohols, but activation energy markedly decreased as the dielectric constant decreased. This proves that the stabilizing activity of these substances cannot be attributed only to the decrease of dielectric constant of the medium. 2) Sugars retarded degradation much more than was expected from the change of dielectric constant. The effect of glucose was particularly distinct. 3) The retardation of degradation by polyhydric alcohols and sugars would be attributed to the binding of hydroxyl ion to metal complex ion consisting of alkaline metal ion, hydroxyl ion, and polyhydric alcohol or sugar. Distinct retardation by glucose may be attributed to its relatively large value of pK.

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3, 6-Dinitrophthalic acid gives a sensitive but unstable color reaction with reducing sugars when heated in sodium carbonate solution in the absence of sodium thiosulfate. This feature can be utilized in the approximate estimation of blood sugar and urine sugar with the naked eye. Basic zinc carbonate is successfully used in deproteinization of blood.

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The results of acid catalyzed epimerization of (-)-2'-benzoylemetine, which possesses the same configuration as the original alkaloid, and of reduction of 2'-benzoyl-5, 11b-dehydroemetinium salt, and the presence of trans-quinolizidine bands in infrared spectra of (-)-2'-acylemetines suggested that (-)-emetine should be represented by (Ia) or (IV), alternatively. The large negative contribution of C-11b hydrogen of (-)-2'-acylemetine to the [M]_D value gave evidence for (Ia) as the absolute configuration of (-)-emetine.

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The structure of orixine (I) was established by the comparison of its decomposition products with the catalytic reduction products (VII) of kokusagine as well as with (XI) derived from dihydrokokusagine.

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Bioconversions of several cardiac aglycones by a strain of Gibberella saubinettii (MONT.) SACC. were repoted. Digitoxigenin was converted to digoxigenin in a good yield. Digitoxigenone was transformed into 3-dehydrodigoxigenin, 3-epidigitoxigenin, and 3-epidigoxigenin. Diginatigenin was obtained in approximately 6% yield from gitoxigenin. Oleandrigenin gave 16-monoacetyldiginatigenin (ca. 15% yield) and diginatigenin (ca. 2%yield), but the formation of gitoxigenin from oleandrigenin by incubation was found to be quite small. Enzymatic hydrolysis of 16β-acetoxyl group of the cardenolide was discussed.

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16-Monoacetyldiginatigenin was converted into diacety1-△^{14, 16}-dianhydrodiginatigenin, which was identical with diacety-△¹⁴-anhydro-16, 17-dehydrodigoxigenin prepared from digoxigenin. Thus, the structure of diginatigenin has been definitely established as 3β, 12β, 14, 16β-tetrahydroxy-5β-card-20(22)-enolide(I).

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1-Substituted 6-chloro-1H-imidazo[b]pyridine was prepared. The Mannich reaction of 6-bromoimidazo[b]pyridine and the behavior of its product in the alkylation reaction were described.

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1, 1-Bis(2-chloroethyl)hydrazine and its hydrazide- and hydrazone- type derivatives were prepared and investigated as to their chemical reactivity and anti-tumor activity against the Yoshida sarcoma.

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Nitration of 3-methoxypyridazine 1-oxide (I) afforded 3-methoxy-4-nitropyridazine 1-oxide (II) and 3-methoxy-4, 6-dinitropyridazine 1-oxide, showing that the positions ortho and para to the N-oxide group are reactive to electrophilic substitution.

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1) 4-Benzamido-6-chloro-3-pyridazinol (IV) was obtained from 4-amino-6-chloro-3-pyridazinol (III) by heating with benzoyl chloride under reflux in the presence of pyridine or nitrobenzene as a solvent. 2) 2-Phenyl-6-chlorooxazolo[5, 4-c]pyridazine (I) yielded (III) and (IV) on heating with sodium hydroxide solution and hydrochloric acid, respectively.

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Im Zusammenhang mit den fruheren Untersuchungen uber Algen-Sterine wurden diesmal die Sterin-Bestandteile der grunen Meeres-Algen untersucht. Aus Monostroma nitidum WITTROCK wurden namlich das Triterpenoid, Friedelin und ein Sterin, das vermutlich das Haliclonasterin was, isoliert. Bei der Aufarbeitung des Sterin-Bestandteils von Enteromorfa linza L. ergab sich ein Stigmastadienol, dessen Eigenschaften mit denjenigen des △⁵-Avenasterins identisch waren. Der Sterin-Gehalt der grunen Alge war kleiner als derjenige der roten bzw. braunen Alge.

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The oxygen atom of 3-chloropyridazine N-oxide was, as in the case of 3-methoxypyridazine 1-oxide, proved to be in 1-position.

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