It was presumed in the previous paper that sumithion was easily absorbed from the gastrointestestinal tract, similarly to methylparathion, following the oral administration to mammals. Inhibition of blood and brain cholinesterase of Guinea pigs and white rats in vivo after oral treatment with sumithion and methylparathion was determined. Inhibition of the enzymes was found to proceed rather rapidly and in most cases it reached maximum within one hour. Sumithion hindered the brain cholinesterase activity far less effectively than methylparathion. Intravenous administration of these phosphorothioates and their oxygen analogs clarified that the latters were more inhibitory on the cholinesterases and that of the two oxygen analogs, sumioxon was less effective. The poor susceptibility of the brain enzyme to sumithion was also observed in this case. This paper deals with the experimental results and their possible implications in the toxicity of the organophosphorus compounds toward mammals.

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A fungus, Paecilomyces variotiBainier TPR-220 was found to produce an acid-protease on wheat bran culture (Koji). The protease showed the highest activity at pHs between 2.5 and 3.0 on casein as substrate. The enzyme was stable at pHs from 2.5 to 6.0 at 40°C for forty minutes. By crystallization from 50% acetone solution the specific activity of the protease was increased five times as high as that of the original crude enzyme preparation.

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3-Pyridylmethylamines, such as 3-pyridylmethyl-N-diethylamine, N-(3-pyridylmethyl)-piperidine and 3-pyridylmethyl-N-dimethylamine provided with the essential moiety of nicotinoids molecule, show comparable toxicity to nicotine against house flies.
3-Pyridylmethylamine without substituent on amino-nitrogen, N-(3-pyridylmethyl)-morpholine having low basic nitrogen, 4-pyridylmethyl-N-diethylamine not provided with proper N-N distance and some nicotine-methiodides having quaternary nitrogen show low or no toxicity.
These data support our proposition that the essential moiety of nicotinoids molecule responsible for high toxicity is 3-pyridylmethylamine grouping.

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Methyl 3-acetamido-3, 5-dideoxy-D-xylofuranosides (VIIIa, VIIIb) were prepared from Dxylose. The glycoside linkage of α-anomer (VIIIa) was more easily hydrolyzed to 3-acetamido-3, 5-dideoxy-D-xylose (X) by acid than that of β-anomer (VIIIb). Reduction of X gave 3-acetamido-3, 5-dideoxy-D-xylitol (XIV), which was hygroscopic syrup.

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Nodakenetin and marmesin were synthesized from β-resorcylaldehyde through 2-(α-hydroxyisopropyl)-6-hydroxycoumaran.

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Friedel-Crafts reaction using BF₃ catalyst was investigated in order to synthesize various carbonyl compounds.

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Several properties of partially purified phosphoprotein phosphatase from chick embryo are described. The enzyme was active toward casein, phosvitin and phosphopeptone, but not toward low molecular weight phosphate esters including aliphatic and aromatic phosphomonoesters, a phosphodiester, pyrophosphates and phosphoamides. The enzyme was not activated by reducing compounds. Heavy metal ions and sulfhydryl inhibitors inhibited the enzyme activity, but the inhibited enzyme was partially reactivated with cysteine. Metal chelating agents also inhibited the activity. To the oxalate treated enzyme, Fe⁺⁺and Co⁺⁺had a stimulatory effect. Differences in property between phosphoprotein phosphatases of chick embryo and of mammalian tissues are discussed.

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Incubating the dried cells ofBrevibacterium sojaeNo.425-40 in alkaline buffer, the excretion of 5'-nucleotides accompanying with the decrease of intracellular RNA was observed. Then the determination of the optimum condition of the excretion and the investigation on the enzyme responsible for the degradation of endogenous RNA were carried out.
In the experiments using sonicate and disrupted cells, it appeared that orthophosphate and Mg⁺⁺might be accelerative or essential for the degradation of endogenous RNA and, in addition to four 5'-nucleotides (AMP, GMP, UMP and CMP), each nucleoside 5'-diphosphate was also contained in its degraded products. Nucleoside 2'- or 3'-monophosphates were not detected. Although it was not clear whether phosphodiesterase concerned with the degradation of intracellular RNA or not, it was suggested that polynucleotide phosphorylase acted mainly on the degradation.
The maximal excretion of 5'-nucleotides from dried cells was obtained by suspending 1 to 2% of dried cells in 0.05M carbonate-bicarbonate buffer (pH 10) and incubating it at 60°C for two to three hours. Orthophosphate and Mg⁺⁺were not required for the excretion.

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The effect of substituents on phosphorus of saligenin cyclic phosphorus esters on inhibitory activities toward cholinesterases and ali-esterases in vitro and in vivo was studied. The most insecticidal methyl derivative was the strongest inhibitor of insect cholinesterase both in vitro and in vivo. When the size of the substituent increased, the specificity toward aliesterase increased, while decreased toward cholinesterase. The inhibitor ratio (I₅₀ ChE/I₅₀AliE) appears to relate closely with insecticidal activity. Non-insecticidal aryl derivatives are very specific to inhibit insect ali-esterase. They are very weak inhibitors of insect cholinesterase in vivo. Their thiono analogs are stronger in vivo than corresponding oxo analogs.

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Herbicidal activity of some 50 pyridazyl ethers was evaluated. Among them, 3-chloro-6-(2-phenylphenoxy)-, 3-chloro-6-(2, 6-dichlorophenoxy)-, 3-chloro-6-(3-methoxyphenoxy)-and 3-chloro-6-(4-methoxyphenoxy)-pyridazines showed conspicuous effectiveness on radish and milletin pre-emergence test, whereas postemergent activity of the compounds tested was not so remarkable in general. Relationships between herbicidal activity and chemical structure are discussed.

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