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51.
Toshio Fujita Katsuzo Kamoshita Takaaki Nishioka Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(8):1521-1528
The electronic and hydrophobic substituent parameters of a number of o-, m- and p- substituted phenyl N-methylcarbamates were estimated by measuring the alkaline catalyzed hydrolysis rate constant and 1-octanol/water partition coefficient. Since some o-substituted derivatives are very potent insecticides, emphasis was placed on determining the ortho substituent effects in terms of the existing free-energy related parameters. The information obtained should be useful in structure-activity studies of carbamate insecticides. 相似文献
52.
Hiroshi Meguro Toshio Konno Katura Tuzimura 《Bioscience, biotechnology, and biochemistry》2013,77(4):945-947
Antifungal activities were examined and compared for some 40 kinds of aliphatic and aromatic aldehydes, alcohols, phenolic compounds, ether compounds and hydrocarbons from essential oils and for some related compounds, using seven fungi. 相似文献
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Toshio Yoshida Shigeru Muraki Hiroshi Kawamura Akira Komatsu 《Bioscience, biotechnology, and biochemistry》2013,77(3):343-352
The main component of Japanese Ho-leaf oil has been shown to be (?)-linalool (80~90%), and the following twenty minor constituents newly have been identified; methyl vinyl ketone, methyl isobutyl ketone, mesityl oxide, β-pinene, myrcene, (+)-limonene, cis- and trans-ocimene, n-hexanol, cis-3-hexenol, cis- and trans-linalool oxide, (?)-1-terpinen-4-ol, (+)-cis and (+)-trans-2,6,6-trimethyl-2-vinyl-5-hydroxytetrahydropyran, citronellol, nerol, (+)-β-selinene, (+)-tagetonol and (?)-trans-hotrienol. (+)-Tagetonol and (?)-trans-hotrienol have been demonstrated to be (+)-3,7-dimethyl-3-hydroxy-1-octen-5-one (III) and (3R)-(?)-trans-3,7-dimethyl-3-hydroxy-1,5,7-octatriene (IX), respectively. 相似文献
56.
Toshio Muto Ryozo Sugawara Katsuhiko Mizoguchi 《Bioscience, biotechnology, and biochemistry》2013,77(5):624-627
A house fly attracting substance, referred to as D3 in the preceeding paper,1) was identified with 1,3-diolein.Among the related compounds, 1- and 2-monoolein and α,ω-glycol monooleate with the formula: CH3(CH2)7CH=CH(CH2)7COO(CH2)nOH (n≦6), were found to have activities ten times that of 1,3-diolein. 相似文献
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Masashi Sumimoto Toshio Suzuki Tainio Kondo 《Bioscience, biotechnology, and biochemistry》2013,77(5):1061-1065
Oxidation of d-Iimonene with selenium dioxide-hydrogen peroxide affords (+)-l-hydroxyneodihydrocarveol as the major product formed via cis- and trans-limonene epoxide. Hydrolysis of the former epoxide is much faster than that of the latter, which can therefore be obtained in almost quantitative yield on acid hydrolysis of a mixture of cis- and trans-limonene epoxide (1:1) under mild condition.Minor significance of oxygenation in an allylic position to a trisubstituted double bond and the difference of accessibility of an allylic position to di- and trisubstituted double bond toward the oxidant were also observed. 相似文献
59.
Toshio Fujita Hiroshi Deura Mitsugi Senda Toshimichi Ikegami Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(8):1192-1197
The kinetics of decomposition of the 3-substituted-phenyl-1-nitroso-1-methylureas was studied under a certain pH and various temperatures. It was observed that the rate of decomposition is first order in concentration of the nitroso compound under the constant pH and that the more the electron withdrawal of the ring substituent, the larger is the rate of decomposition. From the temperature dependence of the rate, the apparent enthalpy and entropy of activation were determined. The sequence of the rate of decomposition of this series of compounds was found to be governed largely by the variation of the entropy rather than that of the enthalpy of activation. 相似文献
60.
Kohei Fujikura Tomiyoshi Setsu Kenji Tanigaki Takaya Abe Hiroshi Kiyonari Toshio Terashima Toshiaki Sakisaka 《PloS one》2013,8(1)
We describe a novel spontaneous mouse mutant, laggard (lag), characterized by a flat head, motor impairment and growth retardation. The mutation is inherited as an autosomal recessive trait, and lag/lag mice suffer from cerebellar ataxia and die before weaning. lag/lag mice exhibit a dramatic reduction in brain size and slender optic nerves. By positional cloning, we identify a splice site mutation in Kif14. Transgenic complementation with wild-type Kif14-cDNA alleviates ataxic phenotype in lag/lag mice. To further confirm that the causative gene is Kif14, we generate Kif14 knockout mice and find that all of the phenotypes of Kif14 knockout mice are similar to those of lag/lag mice. The main morphological abnormality of lag/lag mouse is severe hypomyelination in central nervous system. The lag/lag mice express an array of myelin-related genes at significantly reduced levels. The disrupted cytoarchitecture of the cerebellar and cerebral cortices appears to result from apoptotic cell death. Thus, we conclude that Kif14 is essential for the generation and maturation of late-developing structures such as the myelin sheath, cerebellar and cerebral cortices. So far, no Kif14-deficient mice or mutation in Kif14 has ever been reported and we firstly define the biological function of Kif14 in vivo. The discovery of mammalian models, laggard, has opened up horizons for researchers to add more knowledge regarding the etiology and pathology of brain malformation. 相似文献