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961.
Kanazawa Y Tsuchiya Y Kobayashi K Shiomi T Itoh J Kikuchi M Yamamoto Y Nishiyama H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,12(1):63-71
New asymmetric conjugate reduction of beta,beta-disubstituted alpha,beta-unsaturated ketones and esters was accomplished with alkoxylhydrosilanes in the presence of chiral rhodium(2,6-bisoxazolinylphenyl) complexes in high yields and high enantioselectivity. (E)-4-Phenyl-3-penten-2-one and (E)-4-phenyl-4-isopropyl-3-penten-2-one were readily reduced at 60 degrees C in 95 % ee and 98 % ee, respectively, by 1 mol % of catalyst loading. (EtO)2MeSiH proved to be the best hydrogen donor of choice. tert-Butyl (E)-beta-methylcinnamate and beta-isopropylcinnamate could also be reduced to the corresponding dihydrocinnamate derivatives up to 98 % ee. 相似文献
962.
963.
Transition metal-catalysed acylation of alpha,beta-unsaturated carbonyl compounds with acylstannanes
Shirakawa E Yamamoto Y Nakao Y Tsuchimoto T Hiyama T 《Chemical communications (Cambridge, England)》2001,(19):1926-1927
Acylstannanes were found to add to such alpha,beta-unsaturated carbonyl compounds as enones or ynoates in the presence of a nicel or palladium catalyst to give 2-stannyl-4-oxoalk-2-enoates or 1,4-diketones, whereas the three component coupling between acylstannanes, enones and aldehydes provided 2-hydroxymethyl 1,4-diketones. 相似文献
964.
965.
966.
N Yamamoto S Homma Y Nakagawa M Hayami H Imanaga M Kurimoto M Mitsuhashi T Kimoto 《Journal of photochemistry and photobiology. B, Biology》1992,13(3-4):295-306
The cyanine photosensitizer, lumin, is a potent macrophage activating agent: 4 days after administration of small amounts of lumin to mice (20-40 ng mouse-1), peritoneal macrophages exhibited a greatly enhanced Fc-mediated ingestion activity; higher doses (more than 3000 ng mouse-1) did not have this effect. The in vitro photodynamic activation of macrophages in mouse peritoneal cells exposed to white fluorescent light (3 J m-2 s-1) was also studied in media containing various concentrations of lumin. A short light exposure (45 J m-2) with 10 ng lumin ml-1 produced a maximum ingestion activity of macrophages. Lumin has absorption peaks at 670 and 760 nm. Therefore we designed experiments in which peritoneal cells were exposed to a red fluorescent light (emission, 660 nm; 0.5 J m-2 s-1). In a medium containing 3 ng lumin ml-1 with 7.5 J m-2 of red light, a markedly enhanced ingestion activity of macrophages was observed. The photodynamic treatment of peritoneal macrophages alone did not stimulate phagocytic activity, but the photodynamic treatment of a mixture of non-adherent (B and T) cells and macrophages resulted in a greatly enhanced ingestion activity of macrophages. Thus non-adherent cells are required for the photodynamic activation of macrophages, implying that an activating factor is generated within the non-adherent cells and transmitted to the macrophages. This hypothesis was confirmed by the observation that co-cultivation of photodynamically treated non-adherent cells with untreated macrophages resulted in a greatly enhanced ingestion capacity. 相似文献
967.
J. Kenneth Hoober Theodore W. Sery Nobuto Yamamoto 《Photochemistry and photobiology》1988,48(5):579-582
Abstract— Two easily prepared derivatives of chlorophyll,purpurin–18 and chlorin p 6 , are potent sensitizers of cell killing by low-intensity red light. The internal anhydride group inpurpurin–18 provides the potential of covalently linking in one step the chlorin to cell targeting agents such as antibodies. 相似文献
968.
T Kosuge M Yokota K Sugiyama T Mure H Yamazawa T Yamamoto 《Chemical & pharmaceutical bulletin》1985,33(12):5355-5357
969.
Kenji Miyatake Mitsutoshi Jikei Kimihisa Yamamoto Hiroyuki Nishide Eishun Tsuchida 《先进技术聚合物》1992,3(7):401-405
The electrophilic reaction of sulfur dichloride with diphenyl sulfide proceeds efficiently at room temperature to yield oligo(phenylene sulfide) in the presence of a catalytic amount of Fe powder. Sulfur dichloride shows higher reactivity than sulfur monochloride. The reaction is promoted through the activation of sulfur dichloride by Fe powder. The polymeric product contains a linear structure linked by disulfide and sulfide bonds. 相似文献
970.
M. Imoto H. Yoshimura M. Yamamoto T. Shimamoto S. Kusumoto T. Shiba 《Tetrahedron letters》1984,25(25):2667-2670
A total synthesis of 2,2′-N; 3,3′-O-tetraquis[(R)-3-hydroxytetradecanoyl]-β(1–6)-D-glucosamine disaccharide 1,4′-diphosphate is described. This is the first confirmation of the fundamental structure of lipid A since the synthetic compound exhibited most of the characteristic biological activities of natural endotoxin. 相似文献