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301.
Ishii T Otsuka H Kataoka K Nagasaki Y 《Langmuir : the ACS journal of surfaces and colloids》2004,20(3):561-564
PEGylated gold nanoparticles with biotin moieties installed at the distal end of the PEG tethered chains were prepared by the autoreduction of HAuCl4 catalyzed by alpha-biotinyl-PEG-block-poly[2-(N,N-dimethylamino)ethyl methacrylate] (biotinyl-PEG/PAMA) in aqueous medium at room temperature. The size of the gold nanoparticles was controllable in a range of 6-13 nm by changing the initial Au3+/polymer ratio, while retaining their narrow size distribution. The dispersion stability of the nanoparticles in aqueous medium was extremely high even under the condition of salt concentration as high as I = 2.0. Biotinyl-PEG/PAMA-anchored gold nanoparticles underwent specific aggregation in the presence of streptavidin, revealing their promising utility as colloidal sensing systems applicable under biological condition. 相似文献
302.
The synthesis and characterization of titanium complexes of the aryloxido-functionalized N-heterocyclic carbene ligand (L) is reported, in which the tridentate L ligand meridionally coordinates to the metal center. 相似文献
303.
Toshio Honda Hidenori NamikiHiromasa Nagase Hirotake Mizutani 《Tetrahedron letters》2003,44(15):3035-3038
Enantiospecific total synthesis of an indolizidine alkaloid, ipalbidine, was achieved starting from (−)-pyroglutamic acid by employing an intramolecular McMurry coupling reaction with a low-valent titanium, as a key step. 相似文献
304.
Nishida H Miyazaki Y Mukaihira T Shimada H Suzuki K Saitoh F Mizuno M Matsusue T Okamoto A Hosaka Y Matsumoto M Ohnishi S Mochizuki H 《Chemical & pharmaceutical bulletin》2004,52(4):459-462
Compounds containing an ethylenediamine structure in place of the piperazine ring of M55113 (1) and M55551 (2) were synthesized to investigate the effects of a piperazine moiety and evaluated for activity as factor Xa (FXa) inhibitors. Most such compounds, however, exhibited lower activity (1/10-1/100) than that of M55113 and M55551 as FXa inhibitors. 相似文献
305.
Tatsuro Ouchi Satoshi Jokei Hirotoshi Fujie Hidenori Chikashita Takeshi Inoi 《Journal of heterocyclic chemistry》1984,21(4):1023-1024
In order to provide a less toxic 5-fluorouracil derivative, 1,2:5,6-di-O-isopropylidene-3-O-[3-(5-fluorouracill-yl)-propionoyl]-α-D-glucofuranose, which was the derivative of 5-fluorouracil combining indirectly to 3-position of diacetoneglucose, was synthesized, and its antitumor activity was tested. 相似文献
306.
All of the enantiomers of the title compounds, the components of the pheromone of the olive fruit fly ( Gmelin), were synthesized from ()-malic acid. 相似文献
307.
(3,6)-(?)-3-Hydroxy-1,7-dioxaspiro[5.5]undecane 3a and its antipode were synthesized from ()-malic acid. 相似文献
308.
Total syntheses of (+)-cytisine, (-)-kuraramine, (-)-isokuraramine, and (-)-jussiaeiine A were achieved via a samarium diiodide-promoted reductive deamination reaction, followed by simultaneous recyclization of a proline derivative to give the corresponding delta-lactam derivative, as a key step. 相似文献
309.
Nishida H Mukaihira T Saitoh F Harada K Fukui M Matsusue T Okamoto A Hosaka Y Matsumoto M Shiromizu I Ohnishi S Mochizuki H 《Chemical & pharmaceutical bulletin》2004,52(4):406-412
In the course of development of factor Xa (FXa) inhibitor in an investigation involving the synthesis of 1-arylsulfonyl-3-piperazinone derivatives, we found new compounds containing a unique spiro skeleton. Among such compounds, (-)-7-[(6-chloro-2-naphthalenyl)sulfonyl]tetrahydro-8a-(methoxymethyl)-1'-(4-pyridinyl)-spiro[5H-oxazolo[3,2-a]pyrazine-2(3H),4'-piperidin]-5-one (28, M55529) had activity more favorable than those of previously reported compounds. The inhibitory activity of M55529 for FXa is IC(50)=2 nM, with high selectivity for FXa over thrombin and trypsin. 相似文献
310.
Tanaka Manabu Terasaki Hidenori Ushio Masao Lowke John J. 《Plasma Chemistry and Plasma Processing》2003,23(3):585-606
Numerical modeling of free burning arcs and their electrodes is useful for clarifying the heat transfer phenomena in the welding process and to elucidate those effects which determine the weld penetration. This paper presents predictions for a stationary welding process by the free-burning argon arc. The whole region of the welding process, namely, tungsten cathode, arc plasma and stainless steel anode is treated in a unified numerical model to take into account the close interaction between the arc plasma and the molten anode. The time dependent development of two-dimensional distributions of temperature and velocity, in the whole region of the welding process, are predicted at a current of 150 A. The weld penetration geometry as a function of time is thus predicted. It is shown also that different surface tension properties can change the direction of re-circulatory flow in the molten anode and dramatically vary the weld penetration geometry. 相似文献