Water insoluble tomato β-fructofuranosidase (β-FFase) was prepared by embedding it within a polyacrylamide gel and by adsorbing it on CM-cellulose. The activity of freezedried preparations of the embedded β-FFase retained only 25% of their original activity.
The β-FFase adsorbed on CM-cellulose was not released from the carrier at pH values below 5.0. The insolubilized β-FFase was not released by substrate from either carrier.
The optimal pH for embedded β-FFase using sucrose as the substrate was similar to that of the soluble enzyme.
The Km values of both embedded and adsorbed insoluble enzymes were calculated to be 1.4×10^-3M and 6.9×10^-3M, respectively.
There is a slight break with the embedded β-FFase in the Arrhenius plot at 21°C, but not with the β-FFase adsorbed on CM-cellulose. The activation energy of embedded β-FFase at a temperature range above and below the intersection was 15, 600 and 3, 200 cal/mole, respectively. The activation energy of the β-FFase adsorbed to CM-cellulose was 8, 300 cal/mole. The activity of polyacrylamide embedded β-FFase is considerably less inhibited by β-chloromercuribenzoate (pCMB) and silver ions than that of the CM-cellulose adsorbed enzyme.

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A fluorescent reagent 9-vinylacridine reacted with sulfhydryl group of cysteine to yield S-β-(9-acridinylethyl)-L-cysteine which absorbed ultraviolet light with a molar extinction coefficient of 17, 500 at 358 nm and emitted strong fluorescence in aqueous acetic acid.
9-Vinylacridine also reacted quantitatively with sulfhydryl groups of reduced lysozyme and reduced ribonuclease in acidic condition to give acridinylethylared proteins. This reaction enabled determination of sulfhydryl groups in proteins. From the ultraviolet absorption and the fluorescence characteristics of acridinylethylated proteins, the polarity of the environment of cysteine residues were discussed.

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Protoplasts of several strains of Candida yeasts grown on glucose and on n-alkane were prepared effectively by use of the lytic enzyme of Arthrobacter luteus. Protoplasts prepared from Candida albicans, C. guilliermondii, C. intermedia and C. tropicalis could oxidize glucose, but showed very low respiratory activities for n-alkane. However, addition of an appropriate non-ionic detergent restored greatly the activities. Protoplasts from C. lipolytica could hardly oxidize both glucose and n-alkane, and the activity was not recovered by the detergent effective for the above four strains.

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Methanol-utilizing microorganisms were isolated from soil and air. One of the best vitamin B₁₂ producers was identified as Klebsiella sp. No. 101. The bacterial growth and vitamin B₁₂ production were stimulated by addition of organic nutrients, such as yeast extract and peptone, as well as vitamins, such as pyridoxine, nicotinic acid, p-aminobenzoic acid and biotin. Vitamin B₁₂ production was observed only when methanol was used as the sole carbon source. The maximal vitamin B₁₂ production was 130_??_140 μg per liter of the whole culture broth.

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Solutions of low density lipoprotein fraction (LDF) of yolk were frozen at -18°C for 20 hr, and relative turbidity of the thawed solution was measured. Almost no change of relative turbidity was observed in the presence of salts showing lower eutectic temperature than freezing temperature, except salts generating the turbidity change of the protein solution even at more than 4°C and organic acid salts. When LDF solutions containing various amounts of KCl or NaCl were frozen at lower and higher temperatures than their eutectic temperatures, both viscosity and relative turbidity of thawed solution markedly increased only in the case of freezing at the lower temperatures. From the experimental results it was discussed that the progressive removal of water during freezing could give a harmful effect on low density lipoprotein.

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The coagulating properties of DNA polymerase II were investigated using partially purified enzyme. DNA polymerase II did not coagulate at NaCI concentrations higher than 0.3M but coagulated very rapidly at concentrations lower than 0.2M. The coagulation proceeded at 6 hr after the removal of NaCl. DNA and membrane components did not participate in the coagulation of the enzyme. DNA polymerase II coagulated by itself to form oligomer, and the coagulated enzyme did not dissociate by treatment with 0.3M NaCl or 4M urea. Properties of the coagulated enzyme were the same as the uncoagulated enzyme except for heat stability; coagulated enzyme was rather stable to heat treatment.

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An enzyme, tentatively named L-leucine-pyruvate transaminase, was purified homogeneously by the criteria of ultracentrifugation and electrophoresis on a cellulose acetate membrane from Acetobacter suboxydans (Gluconobacter suboxydans IFO 3172). The molecular weight was about 70, 000 and one mole of pyridoxal 5'-phosphate was bound per mole of the enzyme as coenzyme. The amino donor specificity was extremely broad and the optimum pH was 5.0. The enzyme exhibit absorption maxima at 280 nm and 332 nm.

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As a result of searching for a lipase-inhibiting substances in the cells and in the culture medium of Candida paralipolytica, it was shown that several glycerophospholipids from the cells inhibited the activity of the lipase from the yeast. Three phospholipids were identified as phosphatidylethanolamine (PE), phosphatidylcholine and phosphatidylinositol by thin-layer chromatography.
At pH 8.2, all the phospholipids tested were inhibitory, whereas at pH 6.0, at which the yeast was usually cultured, only PE was inhibitory.
Relationship between the inhibition by phospholipids and calcium ions, and effect of the concentration of sodium chloride on the inhibition with PE were also reported.

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In the polyol fermentation by Candida zeylanoides KY6166, which occurred preferentially by keeping the pH of medium at acidic side (below 4.0), phosphate ion played a precise role in the conversion of erythritol fermentation to D-mannitol fermentation. Enzymatic studies on the conversion mechanism provided the following evidences.
The enzymes involved in pentosephosphate cycle were considerably depressed in polyol production phase in which intracellular pH ranged from 5.5 to 5.7. Particularly transaldolase responsible for the synthesis of erythrose 4-phosphate and fructose 6-phosphate from glyceraldehyde 3-phosphate plus D-sedoheptulose 7-phosphate was significantly depressed at pH 5.5. Besides, transketolase which participated directly in the formation of erythrose 4-phosphate from fructose 6-phosphate was significantly inhibited by phosphate ion. Glucose 6-phosphate dehydrogenase was slightly inhibited by phosphate ion.
From these results, the alteration from erythritol fermentation to mannitol fermentation by phosphate ion was explained as the result of the change in the level of erythrose 4-phosphate and fructose 6-phosphate which was caused by the inhibition of transketolase.

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Experiments were performed to estimate the effect of casein reacted with oxidized ethyl linoleate (casein: lipid=2:1, w/w, at 50°C and RH 80.4% for 14 days) on the liver and plasma lipids of young rats. The results were compared with those of the ad libitum or pair feeding controls fed the unreacted casein.
At a 9 % protein level, feeding the reacted casein resulted in depression of growth and enlargement of liver. Content of liver lipids and glycogen increased, whereas that of liver nitrogen and plasma lipids decreased. The increase in liver lipids was attributable to that of triglyceride. Percentage of stearic and arachidonic acids in liver total lipids of rats fed the reacted casein decreased and that of oleic acid increased. The inverse changes were observed in the composition of plasma lipids. Supplementation of 0.5% Lys or 0.5% Lys and 0.3% Met to the reacted casein exhibited no improvement of the growth and liver and plasma lipids. Further addition of 0.3% Thr showed considerable supplementary effects on the liver and plasma lipids. At a 20% protein level, in contrast to the experiments with a low protein level, the content of liver lipids was decreased: this was mainly attributable to the decrease in phospholipid. In liver lecithin, percentage of arachidonic acid decreased, while that of palmitic and linoleic acids increased.
The present and previous experiments indicated that the responses of the liver lipids to the reacted casein or egg albumin markedly differed from each other.

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Acidic metabolites of Sporobolomyces odorus AHU 3246 were analyzed. The methylated acidic fraction was steam-distilled under reduced pressure and in the distillate, isobutyric, n-butyric, isovaleric, n-valeric, 2-oxo-3-methylbutanoic, cis-4-heptenoic, trans-3-heptenoic, 2-oxo-3-methylpentanoic, 2-oxo-4-methylpentanoic, trans-2, cis-4-heptadienoic, benzoic and phenylacetic acid were identified as their methyl esters by GC-MS analysis. Methyl trans-2, cis-4-heptadienoate was synthesized.

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Isolation and culture condition studies were conducted on bacteria capable of growing autotrophically on gaseous hydrogen. One of the isolates, the strain 9-5, showed the most rapid growth. Optimal growth occurred at pH 5.0 to 6.5. Ammonium or nitrate nitrogen was well utilized for growth, but urea and gaseous nitrogen could not be assimilated. Addition of 0.2mM ferrous ion was remarkably effective on bacterial growth. Three kinds of gases, H₂, CO₂ and CO₂ were almost completely assimilated when the ratio of the three components was 65:23:12, respectively. The strain 9-5 grew moderately even in an atmosphere containing 45% oxygen. A small amount of organic substrates such as glucose was shown to be effective at the initial stage of cell growth. As a result of investigations of culture conditions, cultured broth containing 12.4g/liter of dry cell was obtained within 48 hr.

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A stoichiometric study was performed on an autotrophic culture using a bacterium which is capable of growing on gaseous hydrogen and carbon dioxide as the sole energy and carbon source.
The following stoichiometric equation was put forward on the bases of elemental analysis of bacterial cells, determination of gases consumed, production of bacterial cells and total pressure drop in culture flasks for the chemoautotrophic formation of bacterial cells from hydrogen and carbon dioxide,
38.7 H₂+4.1 CO₂+14.8 O₂+0.78 NH₄⁺=C_4.10 H_6.99 O_1.73 N_0.78+35.9 H₂O
The average yield factor based on hydrogen was calculated as about 1.29 and the efficiency of energy conversion was estimated to be approximately 22.4%

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Microbial (enzymatic) hydrolysis of (±)-O-acetyl allethrolone gave (-)-(R)-allethrolone with (+)-(S)-O-acetyl allethrolone. And microbial hydrolysis of (±)-cis and trans-2-allylcyclopentyl acetates gave the low optically active cis and trans-2-allylcyclopentanols with the acetates of their antipodes. Also, the acetates of (±)-primary alcohols with cyclopropane and cyclohexene rings: (±)-chrysanthemyl alcohol, α-cyclogeraniol, were hydrolyzed by microorganisms to give the optically active alcohols in low optical purities Further, synthesis and microbial resolution of racemic hydroxy-trimethylcyclohexanones, useful intermediate for synthesis of compounds related to carotenoids, were tried.

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Both fluorocitrate and fluoroacetate acted on yeast aconitase as an inducer and a stabilizer of the enzyme. Fluoroacetate appeared to function after conversion to fluorocitrate in the cells. Inhibitors of protein synthesis and terminal respiratory system showed a strong inhibitory effect on the inductive formation of aconitase. In addition, these fluorocompounds were also found to induce various microbial aconitases.

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The distribution of cholinesterase activity among microorganisms was investigated using three kinds of thiocholine esters as substrate. Acetylthiocholine-hydrolyzing activity was present in some species belonging to the fluorescent group in genera Pseudomonas. Ps. aeruginosa species exhibited intense activity. An isolated strain, Ps. aeruginosa A-16, showed the highest activity specific for acetylcholine and acetylthiocholine, and was inhibited by neostigmine. Enzyme formation was induced by choline, and was repressed by glucose. Ps. polycolor IFO 3918, which could grow on butyrylcholine as well as acetylcholine as its carbon and nitrogen source, was found to produce two kinds of esterase which hydroyzed acetylcholine or butyrylcholine. These esterases of Ps. polycolor were fractionated with ammonium sulfate. One of them, the butyrylcholine-hydrolyzing enzyme, was inhibited by atropine and eserine, but was not sensitive to repression by glucose.

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Effect of phenoxazine derivatives (actinomycin D, 1, 8-dimethyl-3-aminophenoxazone-2, 3-aminophenoxazone-2, sodium resazurate, gallocyanine, fluorescent blue and capri blue) on amino acid transport in rat small intestine was investigated using tissue accumulation method. Capri blue (CI-51015) inhibited the accumulation of L-leucine, L-alanine and L-valine, and scarcely inhibited that of D-glucose. Kinetic analysis showed that the inhibition of amino acid accumulation by this pigment was non-competitive. Actinomycin D had no effect on amino acids and D-glucose accumulation in vitro at the high and low concentrations of these substances. High concentration of actinomycin D and long period of incubation had no effect, too. Accumulation of amino acids into the intestinal tissue was not significantly decreased or increased by the presence of other phenoxazine derivatives.

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The effects of molecular weight (M. W.) and contents of sulfate group (D. S.) and 3, 6-anhydro-L-galactose (aGal) on water-holding capacity (used as a main index of gelation) were investigated with modified agarose (AG) and agaropectin (AP) sulfates.
In the case of AG with M. W. 3000_??_100, 000, water-holding capacity increased as the M. W. and aGal content increased. On the other hand, the water-holding capacity of AP was influenced markedly by the D. S. value. From these findings, the effects of the above factors on water-holding capacity can be summarized as follows.
AG:M. W.>aGal content>D. S.
AP:D. S.>M. W.>aGal content
3, 6-Anhydro-D-galactose ring formation was observed on alkali treatment of AP sulfate or agar.

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A histidine auxotroph of Corynebacterium glutamicum was found to accumulate L-histidinol in the culture medium. The accumulation of L-histidinol reached a level of 10_??_11 mg as dihydrochloride per ml with a cane molasses medium containing 15% sugar (as glucose), 2_??_3% (NH₄)₂SO₄ and limited amount of L-histidine. When an Escherichia coli strain was mix-cultured with a later phase-culture of the above L-histidinol-producer, 4 mg/ml of L-histidine was produced with the reduction of the L-histidinol accumulation.

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Sophoradin (I) [2', 4, 4'-trihydroxy-3, 3', 5-tris (3-methyl-2-butenyl) chalcone] was synthesized through Claisen-Schmidt condensation followed by demethoxymethylation.
Isoprenylation of p-hydroxybenzaldehyde with 3, 3-dimethylallyl bromide in 10 potassium hydroxide solution gave 4-hydroxy-3, 5-bis (3-methyl-2-butenyl) benzaldehyde (IX). Methoxymethylation of 2, 4-dihydroxy-3-(3-methyl-2-butenyl) acetophenone (IV) and IX afforded 4-methoxymethoxy-IV (XVIII) and 4-methoxymethoxy-IX (XX). Condensation of XVIII and XX in 50% potassium hydroxide solution gave 2'-hydroxy-4, 4'-bis (methoxy-methoxy)-3, 3', 5-tris (3-methyl-2-butenyl) chalcone (XXII). Hydrolysis of XXII with methanolic hydrochloric acid gave I which was identified with natural I by mixed mp, and IR and NMR spectra.

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A new imino acid, one of the precursors of the brown pigment, was isolated from blackened sake-cake by alumina and Dowex55-X8 (H) column chromatography and thinlayer chromatography. Based on NMR, IR and UV spectral data, it was identified as L-3-carboxy-6, 7-dihydroxy-1-methyl-1, 2, 3, 4-tetrahydroisoquinoline and its structure was also confirmed by synthesis. It was suggested that this compound was produced yb the condesation of L-DOPA with acetaldehyde in sake-cake.

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A lytic activity on cell wall of Rhizopus species which was shown by culture filtrate of Bacillus R-4 was separated into two fractions (Fraction I and II) with the lytic activity by means of SP-Sephadex column chromatography.
The lytic activity of the Fraction II was twice as strong as that of the Fraction I and the lytic action pattern on Rhizopus cell wall of the mixture of these fractions was similar to that of the crude enzyme preparation.
The Fraction I was recognized as a kind of proteolytic enzyme and was purified as a ultracentrifugally and electrophoretically homogeneous preparation.
On the other hand, the Fraction II was a kind of carbohydrolase which acted on glycol chitosan and liberated hexosamine from Rhizopus cell wall accompanying the lysis.

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Ethionine-resistant mutants derived from Corynebacterium glutamicum KY 9276 (Thr^-) were found to accumulate L-methionine in culture media. One of the mutants, ER-107-4, which produced 250μg/ml of L-methionine was subjected to further mutagenesis to obtain better L-methionine producers. L-Methionine production increased stepwise by successive endowing such markers as selenomethionine, 1, 2, 4-triazole, trifluoromethionine and methionine hydroxamate resistance. Thus, a mutant multi-resistant to ethionine, selenomethionine and methionine hydroxamate, ESLMR-724, produced 2mg/ml of L-methionine in a medium containing 10% glucose.
Increase of L-methionine production was accompanied by increased levels and reduced repressibility of methionine-forming enzymes. The levels of methionine enzymes in ESLMR-724 increased to 2.5_??_4.2 fold of those in KY 9276. In addition, homoserine-O-trans-acetylase and cystathionine γ-synthase which were strongly repressed by L-methionine in KY 9276 were stimulated by exogenous L-methionine in ESLMR-724. Implications of these results were discussed in relation to the productivity of L-methionine and the regulation of L-methionine biosynthesis.

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Using a minimal medium containing a methionine analog together with a small amount of S-adenosylmethionine (SAM), many SAM requiring mutants which responded only to SAM and not to methionine, S-adenosylhomocysteine, or homocysteine were efficiently isolated from Corynebacterium glutamicum TLD-140 after mutagenesis. Among them, SAM-14 and SAM-19 selected from selenomethionine resistant mutants were subjected to further investigation. Both mutants were unable to grow in a minimal medium and had no detectable activity of SAM synthetase. Both mutants acquired higher resistance to methionine hydroxamate and ethionine as well as to selenomethionine than TLD-140 and produced L-methionine in a medium.
Homoserine-O-transacetylase in SAM-19 was subject to full repression by the addition of excess SAM to the growth medium and was not repressed under SAM limitation, whereas addition of excess L-methionine under SAM limitation caused a partial repression of the enzyme. SAM synthetase as well as L-methionine biosynthetic enzymes in a methionine auxotroph of C. glutamicum was repressed by the addition of L-methionine to the growth medium.
These results suggest that SAM is implicated in the repression of L-methionine synthesizing enzymes in C. glutamicum.

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When Monilinia fiructigena was treated with S-1358 at a concentration of 10μM, both quality and quantity of digitonin-precipitable sterols were markedly altered. The amount of ergosterol which is a major sterol in the control culture was reduced by S-1358 and the concomitant accumulation of obtusifoliol (one of 4α-methyl sterols) and 24-methylenedihy-drolanosterol (one of 4, 4-dimethyl sterols) was observed. The time course study of acetate-U-¹⁴C incorporation into the digitonin-precipitable sterols revealed that 4α-methyl sterols accumulated slowly in the treated culture, while 4, 4-dimethyl sterols accumulated rapidly. The accumulation of the sterols containing “extra” methyl groups suggests that S-1358 blocks demethylation reactions in the conversion from lanosterol to ergosterol in M. fructigena.

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Activities of 7, 8-diaminopelargonic acid (DAPA) aminotransferase, responsible for DAPA synthesis from 7-keto-8-aminopelargonic acid (KAPA) in biotin biosynthesis by microorganisms, were examined in crude cell-free extracts from about 100 strains of bacteria. Brevibacterium divaricatum NRRL 2311 in particular showed significantly high enzyme activity. The enzyme from Br. divaricatum was purified about 5, 000-fold to homogeneity. Characterization of the purified enzyme from Br. divaricatum was performed. The purified enzyme had absorption maxima at 320 nm and 410 nm, as well as at 280 nm. The molecular weight of the enzyme was determined to be 24, 000. Only S-adenosyl-L-methionine showed activity as an amino donor, while L-methionine, which was also active with the crude cell-free extract, showed no activity. 7-Amino-8-ketopelargonic acid was only one-hundredth as active as KAPA as an amino acceptor. Both pyridoxal 5'-phosphate (PLP) and pyridoxamine 5'-phosphate were effective as cofactors. The enzyme activity was strongly inhibited by typical inhibitors of PLP enzyme. An obvious repression of enzyme synthesis was observed on the addition of biotin to the culture medium.

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Fifteen varieties of cell agglutinins which nonspecifically agglutinate 6 kinds of mouse tumor cells were obtained from the culture broths of 180 actinomycetes strains. One of them, the No. 77 cell agglutinin, was partially purified by ethanol precipitation and by ion exchange and gel filtration chromatography. This agglutinin was thermo-labile and its activity varied with temperature and pH. Cell agglutination by this agglutinin was reversed after a short period at pH 6.0, whereas not at pH 7.4. Addition of histidine, histamine, ATP, ADP, EDTA, Ag⁺, Cd²⁺, Cu²⁺, and Hg²⁺ and heat treatment of the cells at 45°C for 10min inhibited the agglutination at pH 6.0. but not at pH 7.4.

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Inhibitions of beef liver D-glycerate dehydrogenase (EC 1. 1. 1. 29) by glycolytic intermediates and by nucleotides were studied kinetically. It was found that these metabolites inhibited the enzyme noncompetitively with the substrate. In order to clarify the relation between the substrate inhibition by hydroxypyruvate and the inhibition by these metabolites, a simple graphical method was applied to analyze the multiple inhibition kinetics of two noncompetitive inhibitors. The presence of a regulatory site was proved by this method and the binding of hydroxypyruvate or the metabolites to this site was responsible for the inhibition of the enzyme activity. It was also shown that the trinitrophenylation of this enzyme caused a remarkable change of the regulatory properties of this enzyme.

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The amino acid composition of beef liver n-glycerate dehydrogenase (EC 1. 1. 1. 29) was determined. Results of sodium dodecyl sulfate gel electrophoresis and measurements of the number of NADH bound by the enzyme and the number of the essential sulfhydryl groups suggested that the enzyme was composed of two identical subunits with the molecular weight of 36, 000. Close relation between the essential sulfhydryl groups and the coenzyme binding site was also suggested. Effect of an alkylating agent (bromopyruvate) with the structure similar to the substrate was studied. Effects of iodoacetate and iodoacetamide were also studied. It was suggested that these reagents behaved as active-site-directed irreversible inhibitors of the enzyme. Bromopyruvate exhibited a high affinity to the enzyme. Iodoacetate (anionic reagent) had a higher affinity than iodoacetamide (neutral reagent).

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The accumulation of vitamin B₁₂ by Klebsiella sp. No. 101 grown on methanol was investigated furthermore. Addition of urea together with ammonium sulfate or ammonium nitrate was more effective than other nitrogen sources tested. Simultaneous addition of metal ions such as ferrous, calcium and manganese, and addition of amino acids such as alanine, valine, leucine, cysteine, cystine, phenylalanine, tyrosine and proline promoted the bacterial growth and vitamin B₁₂ production. Optimal pH for vitamin B₁₂ production was near 7.0. pH adjustment and methanol feeding were effective for the growth and the vitamin formation. Vitamin B₁₂ production was decreased by addition of CN-B₁₂ to the medium at the concentrations more than 100μg per liter.

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Feeding of a threonine-deficient diet to rats weighing approximately 53g or 99g caused a significant rise in liver lipids compared to the control diet containing 7% amino acid mixture. Whereas, when rats weighing approximately 155g were fed either the control diet or the threonine-deficient diet, liver lipid content was essentially the same for both groups. Therefore, in the present paper, young rats were used to clarify the mechanism of liver lipid accumulation in threonine-deficiency. The increase in dietary fat content of the threoninedeficient diet did not prevent the lipid accumulation in rat liver. The rates of in vivo incorporation from radioactive acetate into liver lipids, body lipids and respiratory CO₂ of rats fed either the control diet or the threonine-deficient diet were measured. The threonine-deficient group tended to be lower in total activity of both the liver lipids and body lipids than those of the control group. Thus, these results suggest that the development of this type of fatty liver might not be due to the stimulation of lipid synthesis in the liver. In the serum of rats fed the threonine-deficient diet, the protein content of β-lipoproteins was significantly lower and free fatty acid level tended to be lower than the values of the control animals, respectively. From these results, decreased trasport of lipids from the liver may thus be considered a potential major factor responsible for the excessive lipid accumulation in the liver of rats fed the threonine-deficient diet.

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Several fluorine- and bromine-containing BHC analogs having the γ-configuration were synthesized.

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Two diastereomers of 1, 2, 3, 4, 5-pentachlorocyclohexane⁺⁺ and two diastereomers of tetrachloromonomethoxycyclohexane were synthesized stepwise from diastereomers of 3, 4, 5-trichlorocyclohexene, which had been derived from the DL-(36/45)-, DL-(34/56)- and (346/5)-isomers of 3, 4, 5, 6-tetrachlorocyclohexene⁺⁺ (α-, β- and γ-BTC, respectively) by selective reduction with LiAlH₄. The configurations of all the products and intermediary trichlorocyclohexene isomers were determined by PMR studies.

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Two methyl groups of α-L-glutamyl-α-aminoisobutyric acid which were equivalent in the acidic solution became unequivalent in the aqueous and basic solutions. Such an unequivalence of two methyl groups was not manifested in the cases of γ-L-glutamyl-α-aminoisobutyric acid, α- and γ-L-glutamylisopropylamide, N-glutaryl-α-aminoisobutyric acid and N-glutarylisopropylamine.

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Z-3-Hexenal, a precursor in the biosynthesis of leaf alcohol and leaf aldehyde, was first isolated from fresh tea leaves, Thea sinensis and its structure was confirmed by unequivocal synthetic evidence.

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Two groups of juvenile hormone analogs were synthesized. One lacks the alkyl substituent at C-7. The other possesses the alkyl substituents neither at C-3 nor at C-7. These analogs were almost inactive on Bombyx mori L. Some of them with the alkyl substituent at C-3, however, were active on Tenebrio molitor L. This indicates the very narrow sensitivity of Bombyx mori L. to juvenile hormone analogs.

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Twenty six juvenile hormone analogs with various molecular chain length were prepared and bioassayed using allatectornized 4 th instar larvae of Bombyx mori L. Among methyl or ethyl esters, the chain length of 17 atoms is the optimal for the high juvenile hormone activity on the silkworm.

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In connection with disclosure of a new class of insecticides, the modified phenylacetates, six new optically active α-isopropy-4-substituted phenylacetic acids whose substituents are respectively 4-methyl, 4-methoxy, 4-fluoro, 4-chloro, 4-bromo and 3, 4-methylenedioxy group were prepared by optical resolution and their absolute configurations were determined by comparative ORD with α-isopropylphenylacetic acid derivatives whose absolute configuration is known as (S)-(+). Esters of the (S)-(+) -acids with 5-benzyl-3-furylmethanol were nearly twice toxic to Musca domestica than those of the racemic esters. Optical purities of the resolved acids were determined by GLC and NMR (with Eu-FOD) as (-)-methyl esters.

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The synthesis of 7-deoxy-D-glycero-D-gluco-heptose (1) from 3, 5-O-benzylidene-1, 2-O-isopropylidene-α-D-glucofuranose (2) is described. Oxidation of compound (2) afforded 3, 5-O-benzylidene-1, 2-O-isopropylidene-α-D-gluco-hexodialdo-1, 4-furanose (3), which was then treated with methylmagnesium iodide to give 3, 5-O-benzylidene-1, 2-O-isopropylidene-7-deoxy-α-D-glycero-D-gluco-heptose (4) and its L-glycero-D-gluco isomer (5). Hydrolysis of (4) produced compound (1), which was identical with natural SF-666 A, a fermentation product of Streptomyces setonensis nov. sp.

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