d, l-Derrisic acid (IIa, R': H) was synthesized from d, l-hydroxy-dihydrotubanol (Ve) by Hoesch condensation with a nitrile (VI). The possible optical resolution of d, l-IIa was demonstrated by a conventional “reversed resolution” method.
This communication and previous works constitute the first total synthesis of natural rotenone (Ia).

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L-Homoserine was prepared by the reduction of L-aspartic acidβ-methyl ester with sodium borohydride in water solution without any racemization. The yield of L-homoserine was about 25% of the theoretical amount, and no product other than L-homoserine, L-aspartic acid and L-aspartic acidβ-methyl ester was present in the reaction mixture. The low yield of L-homoserine was ascribed to the hydrolysis of the ester. L-Azetidine-2-carboxylic acid could not be detected in the reaction mixture. In contrast with the reduction of L-glutamic acidγ-esters, the reduction of L-aspartic acidβ-ester was not accompanied by the cyclization.

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On the screening of microorganisms which accumulate ultra violet light absorbingsubstances, some sporogenous bacteria were selected as powerful strains for production of a crystalline substance having a maximum absorption at 2675mμ(pH 6.0in water). These strains were microbiologically examined and named B. subtilis.var. thermophilus. Submerged fermentation was carried out for 48hrs at 37°C in glucose bouillon medium and the isolation of substance was performed by absorptionto active carbon and elution with ammonia water.
On the basis of chemical studies of this crystal, it was identified as urocanic acid.

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In the previous paper, most of the enzymes of the Embden-Meyerhof-Parnas pathwayand glucose-6-phosphate dehydrogenase have been demonstrated to be present in cell-free extracts ofBrevibacterium divaricatum, No.1627. In this paper, the presence of condensing enzyme, aconitase, TPN-linked isocitric dehydrogenase, succinic dehydrogenase, fumarase, DPNlinked malic dehydrogenase, TPN-linked malic enzyme, oxalacetic carboxylase, isocitritase and malate synthetase in cell-free extracts of this bacterium was also demonstrated. From these results it was concluded that a strain ofBrevibacteriumdivaricatumwhich has been found to contain all of the enzymes of the tricarboxylic acid cycle, would be capable of forming the key enzymes of the glyoxylate bypass as well. It suggests that the accumulation ofα-ketoglutaratc involves the glyoxylate bypass besides the tricarboxylic acid cycle in this bacterium.

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5'-Phosphodiestcrase, which degrades RNA into nucleoside-5'-monophosphates but does not attack DNA, is prescnt not only in mycelium but also in culture filtrate of Penicillium citrinum Thom 1131. For the formation of this enzyme pH of the culture medium must be kept below 7.0 during culture, as this enzyme is inactivated rapidly in alkaline solution. The pH optimum of this enzyme is in the region of pH 5. Cysteine, Mg⁺⁺, sodium fluoride, and inorganic ortho-or pyrophosphate are without appredable effect on this enzyme. Nucleoside-5'-monophosphates, which have been regarded as new chemical seasonings, can be produced economically in a large scale by using the microbial 5'-phosphodiesterase.

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Nitrogen balance is shown by the sum of the retentions and losses involving in all the tissue protein. It is questionable, however, whether or on the values obtained by this method show a true requirement of nitrogen needed for the good health of adult animals. We have studied the relationships between nitrogen balance and the liver nitrogen, and liver xanthine oxidase and succinic dehydrogenase in rats fed on diets containing various levels of casein.
We have found that body weight and the liver nitrogen content slightly decreased, and liver xanthine oxidase and succinic dehydrogenase activities decreased considrably at the point of nitrogen equilibrium.
1) The interrelationships between the nitrogen balance and the liver nitrogen content and two liver enzyme activities, xanthine oxidase and succinic dehydrogenase, in adult rats fed on diets containing various levels of casein for 3 weeks have been investigated.
2) It was found that nitrogen equilibrium could be established on about 7% casein level, but the body weight and the liver nitrogen content more or less decreased. The liver xanthine oxidase and succinic dehydrogenase also showed low activity.
3) The limited significance of using the nitrogen intake necessary to maintain the nitrogen equilibrium for the protein requirement was pointed out.

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The glucomannan isolated from holocellulose pulp of Akamatsu (Pinus densifloraSIEB. et ZUCC.) as its triacetate was methylated and the following methylated sugars were obtained by hydrolysis: the 2, 3, 4, 6-tetra-O-methyl ethers of D-glucose and D-mannose (1 part) and the 2, 3, 6-tri-O-methyl ethers of D-mannose and D-glucose (34-37 parts). Periodate oxidation of the glucomannan showed that 1.00 mole of periodate was consumed per mole of hexose unit and 3 moles of formic acid liberated for every 33 hexose units.

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The plant growth activities of the dihydro- and tetrahydro-1-naphthoic acids substituted with a halogen, methyl or nitro group at various positions of the aromatic ring are measured by the pea straight-growth test. The relationship between structure and activity is discussed. The results seem to conform well with the spatial structure hypothesis of Veldstra.

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The plant growth activity of a number of substituted 1-naphthoic acids is measured by the pea straight-growth test. The concept of molecular-complex forming ability which was proposed as a requirement for the activity previously is confirmed with minor revisions.

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The author found a new enzyme which is capable of isomerising maleic acid to fumaric acid. The enzyme was isolated from a bacterium belonging to Pseudomonas sp. and was concentrated to eight times against the original extract. The biochemical properties were determined as follows: the enzyme required glutathione or cysteine for full activity and was inhibited completely by monoiodoacetate and p-chloromercuribenzoate.

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