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排序方式: 共有162条查询结果,搜索用时 15 毫秒
151.
A. Hirashima K. Shinkai E. Kuwano E. Taniguchi M. Eto 《SAR and QSAR in environmental research》2013,24(1):45-54
Abstract The quantitative structure-activity relationship of 39 octopamine (OA) agonists and 12 antagonists against the thoracic nerve cord of the migratory locust, Locusta migratoria L. was analyzed using atom based rigid fit method or flexible fitting offered by PowerFit 1.0 from MicroSimulation. For OA agonists, the more similar to reference compound NC (24) the structure of test compound, the higher the activity, whereas for OA antagonists it was not the case. Antagonists may not interact with the same part of the membrane with which the agonists interact. Taken the part of the membrane with which the agonist interacts as the true receptor, the antagonist may well interact with an area surrounding the receptor including the ionophore. 相似文献
152.
Shin-ichi Hirashima Takaaki Sakai Kosuke Nakashima Nana Watanabe Yuji Koseki Kanako Mukai Yohei Kanada Norihiro Tada Akichika Itoh Tsuyoshi Miura 《Tetrahedron letters》2014
Diaminomethylenemalononitrile organocatalyst 1 efficiently promotes the asymmetric conjugate addition of malonates to α,β-unsaturated ketones to afford the corresponding addition products in high to excellent yields with up to 98% ee. 相似文献
153.
Shin-ichi Hirashima Kosuke Nakashima Yuki Fujino Ryoga Arai Takaaki Sakai Masahiro Kawada Yuji Koseki Miho Murahashi Norihiro Tada Akichika Itoh Tsuyoshi Miura 《Tetrahedron letters》2014
A diaminomethylenemalononitrile organocatalyst with a cinchona motif efficiently promotes the enantioselective conjugate addition of acetylacetone to various nitroalkenes to yield the corresponding addition products in high to excellent yields with up to 89% ee. 相似文献
154.
Singh RS Adachi S Tanaka F Yamauchi T Inui C Harada T 《The Journal of organic chemistry》2008,73(1):212-218
allo-Threonine-derived O-acyl-B-phenyl-oxazaborolidinones are demonstrated to be powerful and highly enantioselective Lewis acid catalysts for the Diels-Alder reaction of simple acyclic enone dienophiles, expanding the scope of ketone dienophiles and dienes. With 10 to 20 mol % of catalyst, the Diels-Alder adducts are obtained in 76-98% ee with high endo-selectivity. The catalyst exhibits high activity for the reaction with the less reactive beta-substituted dienophiles and the less reactive 1,3-cycohexadiene and 1,3-butadiene derivatives. The application of the catalysts to the Diels-Alder reaction of furan is also described. 相似文献
155.
Sato H Sato F Taniguchi M Yamagishi A 《Dalton transactions (Cambridge, England : 2003)》2012,41(6):1709-1712
Vibrational circular dichroism (VCD) spectroscopy was applied to study the stereochemical properties of a star-burst type tetranuclear Ru(III) complex, Δ-(or Λ-)[{Δ-(or Λ-)-Ru(III)(acac)(2)(taet)}(3)Ru(III)] (acac = acetylacetonato; taet = tetraacetylethanato). By comparing the VCD spectra of eight diastereomeric enantiomers, it was shown that the spectra reflected the homo- or hetero-chiral nature of the bridging part connecting the central core and the peripheral region. 相似文献
156.
Tahara K Tadokoro S Kawashima Y Hirashima N 《Langmuir : the ACS journal of surfaces and colloids》2012,28(18):7114-7118
We had previously developed surface-modified poly (D,L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) for use as a cellular drug delivery system. The cellular uptake of PLGA-NPs was mediated predominantly by endocytosis, and this uptake was increased by surface modifications with polymers, such as chitosan (CS) and polysorbate 80 (P80). In the present study, we prepared a cell-sized giant unilamellar vesicle (GUV) that mimics a cell membrane to investigate the interaction between cell membranes and NPs. Endocytosis-like uptake of NPs into a GUV was observed when the NPs were modified with nonionic surfactant P80 probably due to change in viscoelasticity and enhanced fusion activity of the membrane induced by P80. In contrast, unmodified NPs and those modified with CS were not internalized into a GUV. These results suggest that surface properties of PLGA-NPs are an important formulation parameter for their interaction with lipid membranes. 相似文献
157.
Poly(epsilon-caprolactone) (PCL) composite samples were prepared by polymerization and direct molding. The starting compound was epsilon-caprolactone monomer liquid combined with cellulose and inorganic fillers, using aluminium triflate as a catalyst at 80 degrees C, for 6 or 24 h. Cylinder-shaped PCL composite samples with a homogeneously dispersed cellulose filler were prepared with (-)M(n) = 4 600 ((-)M(w)/(-)M(n) = 2.9). The mechanical properties of the PCL composite samples were studied using compression test methods. The strength of a PCL composite with 50 wt.-% cellulose filler (10.8 MPa) was found to be lower than the PCL sample without fillers (19.2 MPa). The biobased content of the PCL composite with 50 wt.-% cellulose filler (51.67%) measured using accelerated mass spectrometry (AMS) was slightly higher than the carbon ratio of cellulose in the starting powder samples (41.3 mol-%). The biobased content of the polymer composite powders by AMS was found not to be affected by the presence of inorganic fillers, such as talc. The rate and extent of biodegradation, caused by Amano Lipase PS, of the PCL composite sample with cellulose filler (40% degradation in 4 d) was the same as that of a PCL sample without the cellulose filler. 相似文献
158.
Fumière O Dubois M Baeten V von Holst C Berben G 《Analytical and bioanalytical chemistry》2006,385(6):1045-1054
In this paper we present a polymerase chain reaction (PCR)-based method for detecting meat and bone meal (MBM) in compound
feedingstuffs. By choosing adequate DNA targets from an appropriate localisation in the genome, the real-time PCR method developed
here proved to be robust to severe heat treatment of the MBM, showing high sensitivity in the detection of MBM. The method
developed here permits the specific detection of processed pig and cattle materials treated at 134 °C in various feed matrices
down to a limit of detection of about 0.1%. This technique has also been successfully applied to well-characterised MBM samples
heated to as high as 141 °C, as well as to various blind feed samples with very low MBM contents. Finally, the method also
passed several official European ring trials. 相似文献
159.
Miyazawa T Okabayashi EY Koto F Tanimoto M Okabayashi T 《The Journal of chemical physics》2006,124(22):224321
The millimeter- and submillimeter-wave spectra of the NiI radical in the X (2)Delta(5/2) and A (2)Pi(3/2) states were observed by a source-modulated microwave spectrometer. The NiI radical was generated by a dc glow discharge in the mixture of CH(3)I vapor and Ar gas through the sputtering reaction with a Ni cathode. Observed transition frequencies for each electronic state were independently analyzed using a polynomial energy expression based on Hund's case (c) approximation. The deperturbed rotational constants were also estimated by the perturbation analysis including interaction terms between the ground state and the lowest excited state. 相似文献
160.