The selenium (Se) and mercury (Hg) contents of marine fish and weeds obtained from along the coast of Shikoku Island were determined by neutron activation analysis. To measure the Se content, freeze-dried samples were irradiated for 10 sec and then the radioactivities were counted at the energy peak of ^77mSe (162 keV, half life 17.5 sec) for 30 see with a Ge (Li) detector. As for Hg determination, the samples were irradiated for 5 hr and cooled for an ap-propriate period (2_??_3 weeks) prior to the measurement. The Hg contents were evaluated by subtracting the contribution of 75Se from the total activities of both ²⁰³Hg (279 keV, half life 47 d) and ⁷⁵Se (279.6 keV, half life 120 d). In most of the samples tested, both elements could be measured without any chemical treatment before or after irradiation. However, for the samples containing less than 0.04 μg of Se or Hg, concentration processes were conducted by precipitating the metals after irradiation of the samples. The Se and Hg contents of fish samples were in the ranges of 0.12_??_0.45 ppm and 0.01_??_0.13 ppm, respectively, on a wet weight basis. The sea weeds tested contained very low levels of these elements.

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Reductive dehalogenated compounds of 2, 3-dichloro-l, 4-naphthoquinone (Dichlone), such as 2-chloro-l, 4-naphthoquinone, 1, 4-naphthoquinone and 1, 4-naphthalenediol, were produced during the initial stage of photochemically reacting Dichlone in various solvents either in the presence or absence of oxygen. On longer photoreaction in the presence of oxygen, phthalic acid and phthalic anhydride (phthalic acid mono ester instead of the anhydride in an alcoholic solvent) were isolated as the main products. Minor products of reacting Dichlone in a mixture of benzene and 2-propanol were salicylic acid, 2-chloro-3-hydroxy-1, 4-naphthoquinone, 2-chloro-3-phenoxy-1, 4-naphthoquinone and 2, 3-dichloro-4-hydroxy-l-keto-2-phenyl-1, 2-dihydronaphthalene, and isopropyl 1-chloro-2, 3-dioxo-l-indanecarboxylate.

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Mycobacillin adheres to the surface of seed or seedling but is not absorbed by rice plant tissue, whereas versicolin not only adheres to the surface but is also absorbed and subsequently translocated. The antibiotic re-extracted from the versicolin-treated plant tissue inhibits the growth of Helminthosporium oryzae. Thus mycobacillin is active only topically, while versi-cnlin hnth tonically and svstemicnlly.

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The productivity of β-phenethyl alcohol (β-PA) from styrene by Pseudomonas 305-STR-1-4 was examined under various conditions. Under the optimum condition, 3.27mg/ml of β-PA was produced from 20mg/ml of styrene. The metabolic inhibitor, pyrazole, aided ineffectively producing β-PA more reliably and promptly.
β-PA was extracted from the culture broth and purified to a semi-viscous, light-yellow liquid with a rose-like fragrance. Recovery was 90% and purity was 99.4%. IR spectrum of this liquid was identical with that of authentic sample.
The mechanism of β-PA production by strain 305-STR-1-4 was proposed based on the results of this experiment.

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Naphthalene-assimilating, non-fluorescent Pseudomonas sp. S7K5, isolated from soil using kerosene, produced a water-insoluble red pigment (RP) from a high boiling fraction (HBK, 200 to 230°C) of kerosene. RP was not produced from n-alkanes and aromatic hydrocarbons, such as benzene, naphthalene and phenanthrene. RP production was stimulated by adding limiled amount (0.03%, w/v) of naphthalene to HBK (5.0%, w/v)-mineral salt medium. RP was isolated by chelating with magnesium and crystallized from C₂S-petroleum ether to give dark red needles (mp, 218°C, MW, 316). From spectrometrical experiments of RP and its derivatives, RP was identified as a hydroxybenz [a] anthraquinone bearing a methyl group.

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The flavonoid constituents of defatted soybeans were studied. Two kinds of new natural isoflavones and four kinds of isoflavones were isolated by rechromatography on silica gel and Sephadex LH-20 columns of ethyl acetate extracts.
One of the new isoflavones was identified as 6''-O-acetyl daidzin, C₂₃H₂₂O₁₀, by UV, IR, PMR and CMR, and the four kinds of isoflavones were also identified as daidzein, daidzin, genistein and genistin.
High performance liquid chromatography of the ethyl acetate and acetone extracts were carried out, and six main peaks corresponding to the six isoflavones were recognized.
Glycitein and glycitein-7-O-glucoside were not detected in the soybeans.

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1-(1'-2' S-Nornicotino)-1-deoxy-β-D-fructofuranose was first isolated from flue-cured leaves of Cherry Red tobacco, Nicotiana tabacum, cv. Bright Yellow. Its structure was established spectrometrically and synthetically. This substance was shown to be formed from nornicotine during flue-curing. Its smoking effect was mild.

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The initial four enzymes in shikimic acid biosynthesis, 3-deoxy-D-arabino-heptulosonic acid 7-phosphate synthetase (EC 4. 1. 2. 15), 3-dehydroquinic acid synthetase, 3-dehydro-quinate hydro-lyase (EC 4. 2. 1. 10), and shikimate: NADP oxidoreductase (EC 1. 1. 1. 25), were detected in cell-free extracts of tea plant. No significant difference in the enzyme activities was detected between tea cultivars of low and high flavonoid contents. 3-Dehydroquinic acid synthetase was inhibited by gallic acid, (-)-epicatechin gallate, and (-)-epigallocatechin gallate, but not by L-phenylalaaine, L-tyrosine, L-tryptophan, protocatechuic acid, chlorogenic acid, traps-cinnamic acid, (-)-epicatechin, nor (-)-epigallocatechin. The activities of 3-deoxy-D-arabino-heptulosonic acid 7-phosphate synthetase and 3-dehydroquinate hydro-lyase were not affected by any of the above compounds. 3-Deoxy-D-arabino-heptulosonic acid 7-phosphate synthetase was a particulate-bound enzyme and 3-dehydroquinic acid synthetase was a soluble enzyme in tea plant.

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Carbohydrate pyrolysates obtained at 700°C intensively enhanced mutagenicities of several mutagenic agents on Salmonella typhimurium. The pyrolysates obtained by heating from 1 to 15 min had an enhancing effect on the mutagenicity of a similar level. Of the 8 kinds of carbohydrates tested, sucrose pyrolysate showed the highest enhancing effect. The enhancement of mutagenicity by sucrose pyrolysate was much more effective on aromatic amines such as 2-aminofluorene and 2-aminoanthracene than on polycyclic aromatic hydrocarbons. The enhancing effect of sucrose pyrolysate was exhibited in the presence of a metabolic activation system.

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A fluorescent reagent, N-(9-acridinyl)maleimide (NAM), was used for the determination of thiols in biological samples by high performance liquid chromatography. NAM-labeled glutathione (GSH), homocysteine, coenzyme A (CoA) and cysteine (CySH) were separated on a reversed-phase partition (octadecylsililated silica gel) column with the elution conditions of 0.06 M borate buffer pH 8.8: methanol (13:1) at a flow rate of 0.6ml/min within 15 min. In the absence of CoA in the sample, the elution conditions of 0.1 M borate buffer pH 8.8: methanol (15:1) at a flow rate of 0.8ml/min was used for the separations. Calibration curves were held up to 2.5 pmol for GSH and 11 pmol for CySH. About 0.17 μl of rat blood and 0.03mg of rat liver equivalent to 0.1 nmol of GSH were determined. The sensitivity was 100 times higher than that obtained with an automatic amino acid analyzer.

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Polynuclear aromatic hydrocarbons (PAH) including fluoranthene, pyrene, 1, 2-benzan-thracene, chrysene, 3, 4-benzpyrene (1, 2-benzpyrene) and 1, 12-benzperylene, were identified in sediments from Hirakata Bay. Their concentrations were proved to be in the range from several hundred μg/kg to several mg/kg of dry samples.
Significant positive correlations were statistically found between total amount of PAH and Pb, Hg, Cd, Cu, Zn and ignition loss in bay sediment. In addition, significant positive correlations were statistically found between ignition loss and the content of clay as well as the sum of (clay+silt) contents for both river and bay sediments. Based on the fact, it is presumed that organic substances in sediments are present in an adsorbed form to clay and silt.

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The uptake of copper ion by several green microalgae was investigated. The copper tolerance differed with different species of the green microalgae and Chlamydomonas angulosa was the most copper tolerant green microalga. The amounts of copper taken up by the green microalgae rapidly increased in the first 0.5_??_2 hr and then gradually increased with the passage of time. The amount of copper taken up slightly differed with different species of green microalgae. The relationship between the copper tolerance of the green microalgae and their copper uptake could be classified into four groups: 1) copper tolerant algae which take up large amount of copper, 2) copper tolerant algae which take up small amount of copper, 3) copper sensitive algae which take up large amount of copper, and 4) copper tolerant algae which take up small amount of copper. The amount of potassium in the algal cells rapidly decreased in the first 1_??_2 hr after copper supplying and then gradually increased. The ratios of cupric ion obtained from ESR measurements to the copper amounts from the neutron activation analysis differed with different species of green microalgae. We assumed that some part of cupric ion taken up by green microalgae was reduced to cuprous ion mediated by a metabolic process. About 35_??_83% of copper taken up by green microalgae was released by EDTA washing. For the copper tolerant green microalgae the ratio of copper eluted by EDTA washing was larger than that for the copper sensitive green microalgae. For the green microalgae which took up a large amount of copper the amount of copper eluted by EDTA washing was also large. The distribution of copper differed with different species of green microalgae.

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The uptake of manganese by Chlorella regularis was examined. The amounts of man-ganese taken up by the living Chlorella cells rapidly increased in the first 1 hr after supplying manganese ion and then the rate of increase became slower. The amounts of manganese taken up by Chlorella cells increased with increment of manganese concentration. The rapid uptake of manganese by the living Chlorella cells during the first 1 hr was affected by pH of the solution or the co-existence of divalent cation, and was not so affected by temperature, light, and treatment with metabolic inhibitors. The ratio of manganese eluted with EDTA solution to manganese taken up by the living Chlorella cells decreased with the passage of time. These results suggested that the adsorption on the cell surface was the greater part during the first 1 hr but the ratio of uptake into the inner space of the cells increased with the nassaee of time.

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Some benzophenones substituted with methyl, methoxy, hydroxy or halogen groups inhibited growth and induced chlorosis in various plants. The structure activity relationships about the chlorosis-inducing activity and the growth inhibitory activity of the 3-methyl-benzophenones were well expressed by use of hydrophobic contant π, and Hammett's σ. The highest selectivity for phytotoxic activities against barnyardgrass and the rice plant was with 3, 3'-dimethyl-4-methoxybenzophenone (Methoxyphenone).

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The present study was undertaken to select the most preferred deproteinizing agent for microbiological or chromatographic determination of free amino acids in plasma. The highest quantities of amino acids were obtained from samples treated with picric acid, ethanol or sulfosalicylic acid. It was also found from examining the recoveries of ¹⁴C-labeled amino acids added to plasma following treatment with picric acid, ethanol and sulfosalicylic acid that one kind of deproteinizing agent is not equally effective with all amino acids. Picric acid treatment gave the most reliable results for determination of amino acids except the basic amino acids, alanine and tryptophan. Sulfosalicylic acid was the most recommended depro-teinizing agent for basic amino acids and ethanol was good for the assay of alanine and trypto-phan. The response of n-amino acids to the deproteinizing agents tested was not always similar to that of their L-isomers.

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In a search for alternative pyrethrum synergists, dillapiole, one of the chief constituents of Indian dill (Anethum sowa Roxb.) seed oil has been converted into a number of derivatives. Syntheses of 16 such compounds, their spectrometric characterization and factors of synergism towards pyrethrins against Tribolium castaneum Herbst. are being reported. Some of these compounds showed superior activity to piperonyl butoxide, the most commonly used pyre-thrum synergist.

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The intact globular cell wall peptidoglycan was prepared from Micrococcus lysodeikticus without any mechanical disruption. The purification procedure consists mainly of proteolytic digestion and extractions with hot 5% TCA and with 0.01 N NaOH. The purified preparation showed an amphoteric, heteroporous three-dimensional network structure of the peptidoglycan, which amounted to 77% of the dry weight of the preparation, retaining the chemical and morphological integrity as judged by an electron microscopic observation and chemical analyses.

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A reaction system for galactose 1-phosphate (Gal l-P) production was established in the presence of a high concentration of inorganic phosphate ion in which yeast fermentation was conjugated with the galactokinase activity.
Dried cells of Torulopsis candida IFO 0768, grown on lactose, were used as the galacto-kinase source. The Gal 1-P formed by fermenting the conjugated system of 100mg per ml of T. candida with 50mg per ml of baker's yeast was 45mM during 4 hr of incubation. An addition of 5 or 10mM of adenosine derivatives accelerated Gal 1-P formation more than 1.5 times. The formation of Gal 1-P in this reaction system was significantly affected by the amount of fructose 1, 6-bisphosphate (FBP) accumulated in the reaction medium.

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An α-galactosidase from alfalfa seeds was purified 140-fold by ammonium sulfate frac-tionation, and column chromatography on Sephadex G-100, DEAF- and CM-Sephadex. Polyacrylamide-gel electrophoresis of the purified enzyme showed a single protein band. The molecular weight was estimated to be approximately 57, 000 by gel-filtration. The purified enzyme hydrolyzed p-nitrophenyl α-D-galactoside more rapidly than raffinose. The maximal enzyme activities were obtained at pH 4.0 and 5.5 for p-nitrophenyl α-D-galactoside and at 4.5 for raffinose. The enzyme was shown to be inhibited by Hg²⁺ and Ag⁺ ions, and D-galactose.

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The antioxidative activities of L-amino acids on the methylene blue sensitized photo-oxidation of linoleic acid (LA) were studied in a 40% aqueous ethanol solution at pH 7.0 and 33°C. His and CysH inhibited the photosensitized oxidation of LA, and the antioxidative activity of His was larger than that of CysH. The ratio of the chemical reaction rate constant for His and singlet oxygen (¹O₂) to that for LA and ¹O₂, was similar to the ratio of the ¹O₂ quenching rate constant for His to that for LA. This fact shows that His inhibits the photo-sensitized oxidation of LA by quenching 102 chemically.
On the other hand, CysH reacted with linoleic acid hydroperoxides (LAHPO) or with ¹O₂ and caused the decomposition of LAHPO or the formation of Cys. This fact suggests that CysH inhibits the photosensitized oxidation of LA by decomposing LAHPO or by quenching ¹O₂ chemically.

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The promotive effect of biotin (200_??_500 μg/liter) on L-lysine formation was investigated in Brevibacterium lactofermentum. This effect was observed only when glucose or pyruvate was used as sole carbon source, and accompanied with the specific incorporation of ¹³CO₂ into γ-CH₂ group of L-lysine. Brev. lactofermentum AJ 3445 (AEC^r) could grow on pyruvate medium supplemented with biotin at more than 200 μg/liter, while the same growth was observed with the addition of TCA cycle members or glutamate to pyruvate medium.
Phosphoenolpyruvate (PEP) carboxylase deficient mutant derived from AJ 3445 could not grow on glucose as sole carbon source, but on glucose plus 200 μg/liter of biotin. AJ 3445 grown on lactate medium containing 500 μg/liter of biotin and KHCO₃ contained the biotin-dependent pyruvate carboxylase.
These data suggest that this promotive effect of excess biotin on L-lysine formation may be brought about through the activation of pyruvate carboxylase by biotin.

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A crystalline 3α-hydroxysteroid: NAD⁺-oxidoreductase (EC 1. 1. 1. 50) which had been obtained from the cell-free extracts of Pseudonionas putida NRRL B-11064 in the presence of added polyethylene glycol, was found to be a native monomer form with a specific activity of 63.0 and a molecular weight of 45, 000. Isoelectric focusing exhibited the enzyme to be composed of two isoenzymes: one major part focusing at pH 4.75 and a minor part focusing at pH 5.10. Whereas the enzyme was changed from the monomeric form to a dimeric one with a considerable decrease in the specific activity during the course of crystallization in the absence of the added polyethylene glycol.
The enzyme showed an absolute specificity with regard to 3α-hydroxyl group besides a high requirement for cis A:B fusion of steroids. Typical substrates are cholic acid (Km=1.33×10^-5M), deoxycholic acid, chenodeoxycholic acid, 3α-hydroxy-12-keto-9, 11-cholanoic acid, and etiocholan-3α-ol-l7-one. Conjugated bile acids such as taurocholic acid and glyco-cholic acid are also rapidly oxidized. The pH optima for oxidation of cholic acid and reduction of etiocholan-3, 17-dione were 11.5 and 7.0, respectively. The enzyme could be employed for the sensitive and specific assay of bile acids.

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The occurrence and distribution of flavanone glycosides in the leaves and fruits of many kinds of artificial citrus hybrid plants were investigated by polyamide thin-layer chromato-graphy. The citrus hybrids can be divided into two broad categories, a) those containing rutinosyl glycosides, b) those containing neohesperidosyl glycosides in accordance with the case of natural citrus species. The flavonoid patterns of rutinosyl glycosides are classified into the following groups, a) hesperidin, b) narirutin, c) hesperidin and narirutin, d) didymin and narirutin, e) hesperidin, narirutin and eriocitrin and f) hesperidin and eriocitrin, while the pattern of neohesperidosyl glycosides fall into six groups, a) naringin, b) neohesperidin and naringin, c) neohesperidin, naringin and neoeriocitrin, d) neohesperidin and neoeriocitrin, e) naringin and neoeriocitrin, and f) poncirin, neohesperidin, naringin and neoeriocitrin. It is worthy of note that a hybrid (accession number 1088) between C. unshiu and C. hassaku contains only narirutin. Among the ninty-four hybrids examined, fifty-three varieties were obviously different from female parents in their flavonoid pattern and could be judged as true hybrids by flavonoids but the others could not.
Additionally, a survey of flavonoids in newly found natural pummelo- and Daidai hybrids were carried out in connection with their origin.

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Antibiotic-6016 is a new polyether ionophore produced by Streptomyces sp. The crystal and molecular structure of its thallium salt has been established by a three dimentional X-ray analysis using the heavy-atom method from diffractometer data. Crystals are orthorhombic, space group P2₁2₁2₁, a=18.767, b=22.671, c=12.402 Å, Dm=1.37 (flotation in aqueous KI), Dc=1.38g cm^-3, Z=4. The structure was refined by block-diagonal least-squares method to R=0.056 for 3771 independent observed reflections. The antibiotic molecule contains seven ring system: three five-membered rings take an envelope conformation, while the remaining four six-membered rings adopt a chair conformation. The molecule wraps around the thallium ion. Antibiotic-6016 is the first recognized glycosidated polyether containing the hydroxyl substituent at C₂ and the sugar group at the five-membered ring D.

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The cation selectivity profile of a new monocarboxylic ionophore, antibiotic-6016 has been investigated by measuring the complexation affinities for metal cations and biogenic amines as well as the cation transport activity across an organic solvent barrier.
In a two phase partition study the antibiotic formed the complexes with divalent cations of 2:1 stoichiometry and the cation selectivity sequence are summarized as: Mg²⁺>Mn²⁺_??_Ca²⁺>Sr²⁺_??_Ba²⁺. The antibiotic was also able to complex with monovalent cations of 1:1 ionophore: cation⁺ stoichiometry and the complexation affinity was ranked as: NH₄⁺_??_K⁺>Rb⁺_??_Na⁺>Li_??_Cs⁺.
It is noteworthy that the antibiotic was able to complex with serotonin but was negligible for norepinephrine and histamine. In the bulk cation transport system, it efficiently trans-ported Na⁺, K⁺, Ca²⁺, Ba²⁺ and Rb⁺ through an CCl₄ barrier layer but failed to transport Cs+ and biogenic amines.
It is of great interest that the antibiotic is characterized for first time as a broad cation spectrum ionophore with a remarkable preference for Mg²⁺ in the naturally occurring polyether antibiotics.

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The new type of exopolygalacturonate lyase from Streptomyces nitrosporeus had a mole-cular weight between 32, 400 to 39, 000 in three different determination methods, a S⁰₂₀, _w value of 3.4 S and an isoelectric point of pH 4.05. The purified enzyme contained a relatively large amount of aspartic acid, glycine and about 13 % carbohydrate. The enzyme had higher affinity on 10-30% esterified polygalacturonate than on de-esterified polygalacturonate, but the degradation limit of the substrates by the enzyme was diminished by an increase in methyl ester groups of the substrates.

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The effect of tunicamycin, an inhibitor of protein glycosylation mediated by dolichol, on the cell growth and morphology of several normal and transformed cell lines was studied. The low doses of tunicamycin (0.1_??_0.25 μg/ml) caused marked morphological alterations and a significant inhibition of cell growth in transformed cells after 24 hr but had a minimal effect on nontransformed cells. Similar effects were also observed in nontransformed cells, only when cells were treated with the high dose of tunicamycin (1.0 μg/ml). Moreover, the typical transformed cells which showed tumorigenicity and anchorage independency were generally more sensitive to tunicamycin than the nontransformed cells.
Cell spreading after division was extremely inhibited by tunicamycin, and rounded cells formed blebs and finally detached from the substratum. The dose response of tunicamycin as for the above phenomena differed in nontransformed and transformed cells.

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Acetic acid and glucose were compared in their characteristics as a substrate for L-threo-nine fermentation. Maximum accumulation of threonine was 39.5mg/ml at the yield of 15.3 when acetic acid was employed as a substrate, as compared to 10.3mg/ml (10.0%) in glucose supplied culture. In acetate fed culture, maximum production could be obtained under oxygen limited condition at the value of ^rab/KrM (rate of cell respiration/maximum rate of cell respiration) 0.35_??_0.45. At the ^rab/KrM greater than 0.5, the rate of acetate assimilation increased and homoserine accumulated as a by-product resulting in poor productivity. In glucose supplied culture, however, maximum production occurred under sufficient oxygen supply at the ^rab/KrM 1.0. And oxygen limitation led to lactic acid excretion at the expense of the product. Glucose assimilation was enhanced under oxygen limited condition showing Pasteur effect in marked contrast to complete dependence of acetate assimilation upon oxygen.

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A 1:1 mixture of (Z, Z)-3, 13-octadecadien-l-ol and its (E, Z)-isomer was synthesized by a Wittig reaction whose stereoselectivity was adjusted to give the products in the required ratio. The corresponding acetate mixture is useful as the attractant for Synanthedon hector.

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The both enantiomers of (Z)-5-(1-decenyl) oxacyclopentan-2-one were synthesized starting from resolved acetylenic intermediates. The (R)-form of this lactone is the pheromone of Popillia japonica. The optical purities of the final products were about 90%.

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Metabolism of 2, 4, 4'-trichlorobiphenyl by Acinetobacter sp. strain P6 has been studied. When the incubation was carried out without shaking at 15°C, two isomeric monohydroxy compounds, a dihydrodiol compound, a dihydroxy compound, a meta-cleaved yellow com-pound and a dichlorobenzoic acid were detected by combined gas liquid chromatograph-mass spectrometry. As an additional metabolite, dichlorodihydroxy biphenyl, a dechlorination-hydroxylation product, was also detected. When the incubation mixture was shaken at 30°C, a meta-cleaved yellow compound was readily produced and predominantly accumulated in the reaction mixture upon further incubation. The major pathway of 2, 4, 4'-trichloro-biphenyl by Acinetobacter sp. P6 was considered to proceed oxidatively via 2, ' 3'-dihydro-2', 3'-diol compound, concomitant dehydrogenated 2', 3'-dihydroxy compound and then the 1', 2'-meta-cleaved yellow compound, i.e., 3-chloro-2-hydroxy-6-oxo-6 (2, 4-dichlorophenyl) hexa-2, 4-dienoic acid.

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Water-soluble portion of the smoke condensate of cellulose cigarette was studied and 42 compounds-10 lactones, 6 cyclopentanones (or cyclopentenones), 5 pyrans and other compounds-were either positively or tentatively identified. Of these 42 compounds, 12, such as succinaldehyde, 5-hydroxy-2-pentenone, etc., were identified for the first time in cellulose pyrolyzate. Semi-quantitative estimation of some of the major components in water-soluble portion revealed that 1, 6-anhydroglucopyranose (levoglucosan) was the most abundant, followed by 2-hydroxy-3-methyl-2-cyclopentenone (cyclotene), acetol, 2-hydroxy-5-pentanolide,
etc. Glycolaldehyde which seems to be more abundant than cyclotene on chromatogram could not be estimated because of peak tailing. Of these water-soluble com-ponents, succinaldehyde has very pungent and irritating effect and seems to be a cause of the pungent and irritating odor of cellulose cigarette smoke.

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Methyl (2E, 6E)-10, 11-epithio-3, 7, 11-trimethyl-2, 6-dodecadienoate (the thiirane analog of JH III), 6, 7-epithiogeranyl 4-methylphenyl ether and 6, 7-epithiogeranyl 3, 4-methylenedioxy-phenyl ether were synthesized. An infrared absorption band at _??_1090cm^-1 was attributable to the thiirane group. The biological activity of these three sulfur-containing JH mimics was tested on Culex pipiens, Aedes aegypti and Spodoptera litura to reveal weak or no JH-like activity.

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