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91.
Yasumoto K Nishigami A Kasai F Kusumi T Ooi T 《Chemical & pharmaceutical bulletin》2006,54(2):271-274
2,6-Dimethylheptyl sulfate (1) and 6-methyloctyl sulfate (3) were isolated from Daphnia pulex as the Daphnia kairomones that induced morphological defense of a freshwater phytoplankton Scenedesmus gutwinskii var. heterospina (NIES-802). The absolute stereochemistry at C2 of 1 was determined by (1)H-NMR analysis of the (R)-MTPA ester of alcohol 2. The absolute configuration at C6 of 3 was determined by Ohrui's method applied to alcohol 4. 相似文献
92.
Wei‐Shi Li Prof. Dr. Akinori Saeki Dr. Yohei Yamamoto Dr. Takanori Fukushima Dr. Shu Seki Prof. Dr. Noriyuki Ishii Dr. Kenichi Kato Dr. Masaki Takata Prof. Dr. Takuzo Aida Prof. Dr. 《化学:亚洲杂志》2010,5(7):1566-1572
To tailor organic p/n heterojunctions with molecular‐level precision, a rational design strategy using side‐chain incompatibility of a covalently connected donor–acceptor (D–A) dyad has been successfully carried out. An oligothiophene–perylenediimide dyad, when modified with triethylene glycol side chains at one terminus and dodecyl side chains at the other ( 2 Amphi ), self‐assembles into nanofibers with a long‐range D/A heterojunction. In contrast, when the dyad is modified with dodecyl side chains at both termini ( 2 Lipo ), ill‐defined microfibers result. In steady‐state measurements using microgap electrodes, a cast film of the nanofiber of 2 Amphi displays far better photoconducting properties than that of the microfiber of 2 Lipo . Flash‐photolysis time‐resolved microwave conductivity measurements, in conjunction with transient absorption spectroscopy, clearly indicate that the nanofiber of 2 Amphi intrinsically allows for better carrier generation and transport properties than the microfibrous assembly of 2 Lipo . 相似文献
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Naoki Saito Chieko Tanaka Khanit Suwanborirux Surattana Amnuoypol Akinori Kubo 《Tetrahedron》2004,60(17):3873-3881
The transformation of renieramycin M (1m) into renieramycin J (1j) and jorumycin (2) is presented along with the results of antiproliferative assay data. The chemical stability and the oxidative degradation of 2 and renieramycin E (1e) to generate simple isoquinoline alkaloids, such as mimosamycin (7), renierol acetate (12), and renierone (8) are also described. 相似文献
95.
William J. Hall Nona Merry M. Mitan Thallada Bhaskar Akinori Muto Yusaku Sakata Paul T. Williams 《Journal of Analytical and Applied Pyrolysis》2007,80(2):406-415
The co-pyrolysis of brominated high impact polystyrene (Br-HIPS) with polyolefins using a fixed bed reactor has been investigated, in particular, the effect that different types of brominated aryl compounds and antimony trioxide have on the pyrolysis products. The pyrolysis products were analysed using FT-IR, GC–FID, GC–MS, and GC–ECD. Liquid chromatography was used to separate the oils/waxes so that a more detailed analysis of the aliphatic, aromatic, and polar fractions could be carried out. It was found that interaction occurs between Br-HIPS and polyolefins during co-pyrolysis and that the presence of antimony trioxide influences the pyrolysis mass balance. Analysis of the Br-HIPS + polyolefin co-pyrolysis products showed that the presence of polyolefins led to an increase in the concentration of alkyl and vinyl mono-substituted benzene rings in the pyrolysis oil/wax resulting from Br-HIPS pyrolysis. The presence of Br-HIPS also had an impact on the oil/wax products of polyolefin pyrolysis, particularly on the polyethylene oil/wax composition which converted from being a mixture of 1-alkenes and n-alkanes to mostly n-alkanes. Antimony trioxide had very little impact on the polyolefin wax/oil composition but it did suppress the formation of styrene and alpha-methyl styrene and increase the formation of ethylbenzene and cumene during the pyrolysis of the Br-HIPS. 相似文献
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98.
Shigeo Matsuda Akira Ishikubo Akinori Kuzuya Morio Yashiro Makoto Komiyama 《Angewandte Chemie (International ed. in English)》1998,37(23):3284-3286
Even in the presence of a large excess of Zn II ions , sequence-selective RNA hydrolysis is achieved by DNA conjugates involving a dinuclear ZnII complex (shown schematically). This is because the cooperation of two ZnII ions is essential for the RNA scission. 相似文献
99.
Yoichi Yamaguchi Yosuke Nagasawa Akinori Murakami Kenji Tabata 《International journal of quantum chemistry》1998,69(5):669-678
The stability of oxygen anions and the hydrogen abstraction from methane on a reduced SnO2 (110) crystal surface have been studied theoretically using a point-charge model. The geometric and electronic structures for the present molecules are calculated by means of a hybrid Hartree–Fock/density functional method at the B3LYP/6-311+G(3df, 3pd) level of theory. The calculations of the energies on the point-charge model are performed using these optimized geometries. It is found that a low concentration of the active oxygen species O− and O2− is expected on the reduced SnO2 surface. The activation energies for the abstraction of hydrogen atom from methane on the reduced SnO2 surface are obtained: 12 kcal/mol for O− species and more than 48 kcal/mol for O2− species, indicating that O− species on the surface is the main active center for the dissociation of a C(SINGLE BOND)H bond of methane, which is in agreement with the other oxide catalysts. © 1998 John Wiley & Sons, Inc. Int J Quant Chem 69: 669–678, 1998 相似文献
100.