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81.
Miura T Goto K Waragai H Matsumoto H Hirose Y Ohmae M Ishida HK Satoh A Inazu T 《The Journal of organic chemistry》2004,69(16):5348-5353
The Bfp-OH, a novel fluorous protecting reagent, was able to be easily prepared. The Bfp group was readily introduced to a carbohydrate, removed in high yield, and recyclable after cleavage. The use of the Bfp group made it possible to synthesize a pentasaccharide by minimal column chromatography purification. Each synthetic intermediate was able to be easily purified only by simple fluorous-organic solvent extraction and monitored by TLC, NMR, and MS. 相似文献
82.
4-Fluorinated UDP-MurNAc pentapeptide, 2, has been synthesized. In our previous study, UDP-MurNAc pentapeptide analogue 1 was found to be incorporated into the bacterial cell wall through biosynthesis. Compound 2 showed growth-inhibition activity against Gram-positive bacteria when it was added to growth media at 0.01 mg/mL. [structure--see text] 相似文献
83.
K. Hirose 《Journal of Radioanalytical and Nuclear Chemistry》1996,207(1):193-204
Studies have been made of loose water tritium (LWT) distribution and behavior in the soil samples taken from the region within a radius of 2 km to the HWRR stack of CIAE. The analytical results show that the LWT concentrations in most soil samples of the region are in the range from 24.8 Bq/l (3.6 Bq/kg) to 116 Bq/l (16.0 Bq/kg) with an average value of 58.1±24.8 Bq/l (10.3±4.5 Bq/kg). There are two areas with a higher LWT content; the first one (4.61 · 104 m2) is located near HWRR with ahighest LWT concentration of 287 Bq/l (55.8 Bq/kg) and the second one (3.27 ·105 m2) is located near Lab. A with a highest LWT concentration of 2.35 · 104 Bq/l (2.56 · 103 Bq/kg). It is estimated that the LWT inventories deposited in soil of the two areas are about 1.52 · 109 Bq and 1.42 · 1010 Bq, respectively. The analytical results have been evaluated by comparing the possible tritium intake of the human body with the annual limit of intake recommended by ICRP, it can be concluded that the operations of all the nuclear facilities releasing tritium in CIAE are safe without causing any notable tritium contamination. 相似文献
84.
New low-molecular-weight gelators based on l-valine and l-isoleucine gelators, which have a positively charged terminal group, can gel not only pure water and aqueous solutions containing inorganic acids and salts but also some organic solvents and oils. 相似文献
85.
86.
N-Acyl-α-amino acids are synthesized by the amidocarbonylation of allylic alcohols catalyzed by homogeneous binary systems which consist of cobalt carbonyl and rhodium (or iron or palladium) complexes. 相似文献
87.
Takashi Hirota Kenji Sasaki Yohsuke Tashima Taiji Nakayama 《Journal of heterocyclic chemistry》1991,28(2):263-267
Syntheses of 2,3-dihydrobenzofuro[2,3-e]imidazo[1,2-c]pyrimidine and its 5-substituted derivatives, corresponding to B-nor-6-oxa-11,13,15-triazasteroids, are described. These products and their precursors were screened to evaluate the antidepressive activity. 相似文献
88.
Qi ZM Matsuda N Santos J Yoshida T Takatsu A Kato K 《Journal of colloid and interface science》2004,271(1):249-253
Broadband, time-resolved optical waveguide (OWG) spectroscopy has been used for in situ, real-time investigation into the self-assembly of metal nanoparticle monolayers. The OWG spectroscopy makes it possible to use the transverse electric (TE) and transverse magnetic (TM) modes to measure surface plasmon absorption of immobilized metal nanoparticles in two directions, parallel and normal to the waveguide surface. Therefore, this technique can provide direction-dependent information on the metal nanoparticles at the interface. In this paper, a 50-microm-thick glass plate was used as a slab waveguide and the kinetics of Au nanoparticle adsorption on a hemoglobin-functionalized glass substrate was examined in the early stage of self-assembly. The findings show that with the TE mode the surface plasmon resonance (SPR) behavior for immobilized Au nanoparticles is different from that with the TM mode. 相似文献
89.
(+-)-3,3,7-Trimethyl-2,9-dioxatricyclo[4.2.1.04, 7]noname and (+-)-3,3,7-trimethyl-2,9-dioxatricyclo[3.3.1.04, 7] nonane were synthesized. The latter was shown to be (+-)-lineatin, an ambrosia beetle pheromone. 相似文献
90.