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171.
Several analogs of abscisic acid (ABA) were prepared and their biological activities were assayed. Among the compounds tested, 5-(l, 2-epoxy-2, 6, 6-trimethyl-l-cyclohexyl)-, 5-(l-hydroxy-2, 6, 6-trimethyl-2-cyclohexen-l-yl)- and 5-(l-hydroxy-2-methylene-6, 6-dimethyl-l-cyclohexyl)-3-methyl-cis, trans-2, 4-pentadienoic esters (V, IX, XXIII and XXV) were found to be potent plant growth inhibitors. Their activities were superior or comparable to that of ABA. 相似文献
172.
Rats were divided into low casein diet and high casein diet fed groups, and the fatty acid composition of liver mitochondrial phosphatides was analyzed. It was found that in liver mitochondrial phosphatides the value of arachidonic acid decreased slightly, and that of the polyenoic fatty acid which was infered as 4, 7, 10, 13, 16-docosapentaenoic acid increased by low casein diet. The analysis was performed also on whole liver phosphatides. There was no great difference between the fatty acid composition of whole liver and liver mitochondrial phosphatides 相似文献
173.
Akira Isogai Akinori Suzuki Shizuo Higashikawa Shimpei Kuyama Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(4):1023-1024
The structure of the xyloglucan synthesised in vitro by the particulate fraction of suspension-cultured soybean (Glycine max) cells from UDP-glucose and UDP-xylose is mainly composed of two kinds of oligosaccharide-building blocks, a heptasaccharide unit and a pentassaccharide unit [T. Hayashi and K. Matsuda, J. Biol Chem., 256, 11117 (1981)]. The synthesis of the pentasaccharide unit is probably the first step in the construction of oligosaccharide building blocks to elongate the ²-1,4-glucan backbone. This enzymatically synthesized xyloglucan was shown to have the same molecular size (Mw, 180,000) as the xyloglucan prepared from soybean cell walls by gel filtration on a Sepharose CL-6B column, and the same building blocks distributed among each fraction. A pulse-chase experiment indicated that the pentasaccharide unit was converted into the heptasaccharide unit. The conversion was regulated by the concentration of UDP-xylose. 相似文献
174.
Nobutaka Takahashi Akinori Suzuki Satoshi Miyamoto Rinpei Mori Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(8):583-589
Molecular formula C25H37–39NO4 was assigned to Piericidin A. Through the examination of the ultraviolet, infrared and n.m.r. spectra and of chemical evidences, it was shown that Piericidin A contains one secondary alcohol, one acidic hydroxyl group, two methoxyl groups, tri- and tetra-substituted conjugated dienes and one polysubstituted heteroaromatic ring. 相似文献
175.
Saburo Tamura Shimpei Kuyama Yoshinori Kodaira Shizuo Higashikawa 《Bioscience, biotechnology, and biochemistry》2013,77(2):137-138
The viability of freeze-dried Lactobacillus bulgaricus B-1 was affected by rehydration temperature, and maximum recovery of the viable cells was obtained when they were rehydrated at 20 to 25°C. Cellular ribonucleotides leaked out from the freeze-dried cells during rehydration, but there was no correlation between the viability of cells and the amount of leaked substances. Rehydration of the freeze-dried cells in the presence of RNase caused marked loss of viability. These results suggest that the cell surface was damaged by freeze-drying and its selective permeability was lost to some extent. 相似文献
176.
Goro Tamura Tamioki Hosoi Jun Aketagawa 《Bioscience, biotechnology, and biochemistry》2013,77(11):2165-2167
The intermediate of the aromatization of 4-oxocyclohexanecar-boxylic acid (OHA) to 4-hydroxybenzoic acid (HA) by Coryne-bacterium cyclohexanicum was identified as (+)-4-oxocyclohex-2-enecarboxylic acid (O2A) using a combined system of gas-liquid chromatography (GLC) and a mass spectrometer and polarimeter. 相似文献
177.
Akira Isogai Akinori Suzuki Shizuo Higashkawa Shimpei Kuyama Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(12):3033-3035
( + )-α-Kainic acid (1) was synthesized by starting from a building block, N-Boc-3-acetoxyallylglycine ethyl ester (2). The key intermediate, a methyl 4-[(tert-butoxycarbonyl)prenylamino]-5-hydroxy-2-pentenoate derivative (9), was prepared from 2 in eight synthetic steps. After converting 10 into a methyl ester (11), intramolecular ene-carbocyclization of 11 gave a pyrrolidine derivative (12), which was converted to 1 in a moderate yield. 相似文献
178.
Hiroshi Tanaka Pie-Lang Wang Osamu Yamada Late Teiichi Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(2):107-113
From mycelia of Asp. niger and Asp. awamori aurasperones A, B and C along with related two yellow pigments have been isolated.Aurasperone A, C32H26O10, is obtained in yellow prisms; m.p. 207°C; [α]d —136°; gives the diacetate and the dimethyl ether and is assumed to be a dimeric 2-methyl-5- hydroxy-6,8-dimethoxy-4H-naphtho [2,3-b] pyran-4-one (IV). Aurasperone B, [α]D +46.3°, is the main yellow metabolite, m.p. 186°C, and affords aurasperone A on hydrochloric acid-treatment. It has molecular formula C32H30O12 and is supposed to have the structure (V). The other yellow pigments have been found to be also congeners of aurasperone A. 相似文献
179.
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 millet in 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. 相似文献
180.
Series of 3-chloro-6-phenoxy- and 3,6-bisphenoxypyridazines were prepared from 3,6-dichloropyridazine to be evaluated as herbicides. Certain thioethers were also prepared. 相似文献