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71.
Takahiro Moriyama Daiki Mizukami Dr. Makoto Yoritate Dr. Kazuteru Usui Dr. Daisuke Takahashi Dr. Eisuke Ota Prof. Dr. Mikiko Sodeoka Prof. Dr. Tadashi Ueda Prof. Dr. Satoru Karasawa Prof. Dr. Go Hirai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(11):e202103925
Minimalist photo-reactive probes, which consist of a photo-reactive group and a tag for detection of target proteins, are useful tools in chemical biology. Although several diazirine-based and aryl azide-based minimalist probes are available, no keto-based minimalist probe has yet been reported. Here we describe minimalist probes based on a 2-thienyl-substituted α-ketoamide bearing an alkyne group on the thiophene ring. The 3-alkyne probe showed the highest photo-affinity labeling efficiency. 相似文献
72.
X-ray study of enhydrin bromohydrin, C23H29BrO10, reveals that the crystal has space groupP212121 with cell parametersa =10.08,b = 26.97, andc = 8.94 Å. There are four molecules in the unit cell. The structure was solved by direct methods, with three-dimensional CuK diffractometer data to = 75 °, and refined by block-diagonal least squares to anR index of 11.4% for 2254 reflections. The molecule is a germacronolide sesquiterpene having acis sterochemistry at the C(1), C(10) double bond and atrans configuration at the epoxide ring, C(4)-O-C(5). The absolute configuration established on the basis of the anomalous scattering of CuK. radiation by the bromine atom shows that the asymmetric atoms have the 4R, 5R, 6S, 7S, 8S, 9S, 20S, and 22S configurations. 相似文献
73.
Kazuma Shimoda Takahiro Mitsuoka Kenta Ueda Hiroshi Suemune Go Hirai Mariko Aso 《Tetrahedron letters》2018,59(51):4528-4531
A dendritic bisphosphonate carrying three bisphosphonate (BP) units in close proximity was designed as a ligand to conjugate large therapeutic molecules for their bone selective delivery. The Bu3P-catalyzed conjugate addition of nitromethane to vinylidene bisphosphonate was effective to construct a quaternary carbon center carrying BP units. Owing to multivalent interactions, the dendritic bisphosphonate showed considerable affinity for the bone mineral hydroxyapatite even in the presence of a competitor, demonstrating potential as a bone targeting ligand. 相似文献
74.
Park Il Lee Jin O Do Tae Gwan Kim Min Jun Go A Ra Kim Kwang Pyo 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(3):1213-1219
Journal of Radioanalytical and Nuclear Chemistry - Radiation dose to personnel on the ground contaminated with radioactive cesium after nuclear power plant accident depends on cesium activity,... 相似文献
75.
A software package to determine the non-isothermal kinetic parameters of heterogeneous reactions has been developed. The dynamic handle of conversion degree step and ranges, heating rates and kinetic models makes the evaluation of the activation parameters much faster. The standard procedure: ‘model-free’ kineitc, IKP and Perez-Maqueda et al. methods, is applied for the determination of the kinetic triplet corresponding to thermal induced transformations. The software is designed mainly for thermogravimetric, temperature programmed reduction and dilatometry data processing, but may also import already transformed numeric data. 相似文献
76.
77.
Nishimura G Maehara H Shiraishi Y Hirai T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(1):259-271
An azamacrocyclic ligand (L) containing two anthracene (AN) fragments connected through two triethylenetetramine bridges has been synthesized, in which each of the bridges can coordinate with one metal cation. The effects of pH and metal cations (Zn2+ and Cd2+) on the emission properties of L were studied in water. Without metal cations, L does not show any emission at basic pH values. The addition of Zn2+ leads to the production of excimer emission, which is due to a static excimer formed by direct excitation of the intramolecular ground-state dimer of the bipolar AN fragments that approach each other by Zn2+ binding. In contrast, Cd2+ addition does not result in excimer emission because the Cd2+-AN pi complex, formed by donation of a pi electron of the AN fragments to the adjacent Cd2+, suppresses pi-stacking interactions of the AN fragments. The most notable feature is the appearance of excimer emission controlled by the input sequence of metal cations: Zn2+-->Cd2+ sequential addition (each one equivalent) allows excimer emission, whereas the reverse sequence (Cd2+-->Zn2+) does not. In the Zn2+-->Cd2+ sequence, Cd2+ coordination is structurally restricted by the first Zn2+ coordination with the other polyamine bridge, leading to the formation of a weak Cd2+-AN pi complex. In contrast, for the reverse sequence, the first Cd2+ coordination forms a stable Cd2+-AN pi complex, which is not weakened by sequential Zn2+ coordination, resulting in no excimer emission. 相似文献
78.
The subject of this paper is the long distance propagation of train noise. The sound exposure level of train noise LAE was measured. To describe the results of measurements, a semi-analytical model was used. It takes into account the wave-front divergence, air absorption, ground effect, and the turbulence destroying the coherent nature of the ground effect. The model contains three adjustable parameters that must be estimated at the site. To verify the model, we performed measurements of LAE at the distance D = 450 m from the train track center. The difference between the calculated and measured mean values of LAE equals 1.3 dB. 相似文献
79.
Go Gwang Sub Lee Hong Joo Moon Dong Ju Kim Young Chul 《Research on Chemical Intermediates》2016,42(1):289-304
Research on Chemical Intermediates - In this study, we focused on the catalytic activity, stability, and kinetics of glycerol steam reforming (GSR) for the hydrogen production over... 相似文献
80.