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181.
A simple one-pot synthesis of spiranones from cycloketones and dienes promoted by an ammonium salt generated in situ from diamine and alkoxymethyl chloride through a tandem alpha-methylenation/Diels-Alder reaction is described. 相似文献
182.
183.
Hiroko N Beck Karen Drahushuk David B Jacoby Dennis Higgins Pamela J Lein 《BMC neuroscience》2001,2(1):12-11
Background
BMP-5 is expressed in the nervous system throughout development and into adulthood. However its effects on neural tissues are not well defined. BMP-5 is a member of the 60A subgroup of BMPs, other members of which have been shown to stimulate dendritic growth in central and peripheral neurons. We therefore examined the possibility that BMP-5 similarly enhances dendritic growth in cultured sympathetic neurons. 相似文献184.
185.
Frontispiece: Aromaticity Relocation in Perylene Derivatives upon Two‐Electron Oxidation To Form Anthracene and Phenanthrene 下载免费PDF全文
186.
An Optically and Thermally Switchable Electronic Structure Based on an Anthracene–BODIPY Conjugate 下载免费PDF全文
Tatsuya Aotake Dr. Mitsuharu Suzuki Kazuaki Tahara Dr. Daiki Kuzuhara Prof. Dr. Naoki Aratani Prof. Dr. Naoto Tamai Prof. Dr. Hiroko Yamada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(13):4966-4974
An optically and thermally responsive boron dipyrromethene (BODIPY) dye, namely, meso‐2‐(9,10‐dihydro‐9,10‐ethanoanthracene‐11,12‐dione) (DK)‐linked, bicyclo[2.2.2]octadiene (BCOD)‐fused BODIPY ( BCOD‐DK ), was synthesized. The weakly luminous structure of BCOD‐DK can be changed quantitatively to that of the strongly fluorescent BODIPY BCOD‐Ant by optical excitation at the DK unit, which induces double decarbonylation of the DK unit to give an anthracene unit. The solvent effect on the fluorescence properties of BCOD‐DK suggests that the dramatic change in fluorescence intensity is controlled by intramolecular electron transfer from the BODIPY moiety to the meso‐DK substituent. BCOD‐DK is converted to meso‐ DK benzene‐fused BODIPY ( Benzo‐DK ) by heating at 220 °C with 64–70 nm redshift of absorption and fluorescence peaks without changing the fluorescence quantum yield of ΦF=0.08 in dichloromethane. Benzo‐DK can be converted to strongly fluorescent meso ‐ anthracene benzene‐fused BODIPY Benzo‐Ant by optical excitation. Thus, BCOD‐DK can show four different optical performances simply by irradiation and heating, and hence may be applicable for optical data storage and security data encryption. 相似文献
187.
Shigeyoshi Yamamoto Hiroshi Tatewaki Hiroko Moriyama 《Theoretical chemistry accounts》2012,131(5):1-9
The addition of iron or boron and/or nitrogen, up to 20?%, to amorphous carbon with a density of about 2.0?gm/cm3 was studied using density functional theory. The bulk cohesive energy decreases with increasing iron, nitrogen, or boron concentration. The decrease is largest for iron and smallest for boron. The trends in the bulk moduli are consistent with the cohesive energies. The optical properties (absorbance and reflectivity) of the samples with nitrogen and/or boron added are very similar to those of the original amorphous carbon. Addition of iron results in larger, energy dependent, changes when compared with either boron or nitrogen. The effect of dopants on low-density amorphous carbon shows some differences with those for higher density amorphous carbon. 相似文献
188.
189.
Dr. Hiroshi Hinou Risho Miyoshi Yasuaki Takasu Hirokazu Kai Dr. Masaki Kurogochi Dr. Shingo Arioka Dr. Xiao‐Dong Gao Dr. Nobuaki Miura Dr. Naoki Fujitani Dr. Shinya Omoto Dr. Tomokazu Yoshinaga Dr. Tamio Fujiwara Dr. Takeshi Noshi Dr. Hiroko Togame Prof. Hiroshi Takemoto Prof. Shin‐Ichiro Nishimura 《化学:亚洲杂志》2011,6(4):1048-1056
A potent inhibitor for Vibrio cholerae neuraminidase (VCNA) was developed by using a novel two‐step strategy, a target amino acid validation using mechanism‐based labeling information, and a potent inhibitor search using a focused library. The labeling information suggested the hidden dynamics of a loop structure of VCNA, which can be a potential target of the novel inhibitor. A focused library composed of 187 compounds was prepared from a 9‐azide derivative of 2,3‐dehydro‐N‐acetylneuraminic acid (DANA) to interrupt the function of the loop of the labeled residues. Inhibitor 3c showed potent inhibition properties and was the strongest inhibitor with FANA, a N‐trifluoroacetyl derivative of DANA. Validation studies of the inhibitor with a detergent and a Lineweaver–Burk plot suggested that the 9‐substitution group would interact hydrophobically with the target loop moiety, adding a noncompetitive inhibition property to the DANA skeleton. This information enabled us to design compound 4 having the combined structure of 3c and FANA. Compound 4 showed the most potent inhibition (Ki=73 nM , mixed inhibition) of VCNA with high selectivity among the tested viral, bacterial, and mammal neuraminidases. 相似文献
190.
Hiroko Morimoto 《Journal of Mathematical Fluid Mechanics》2007,9(3):411-418
Let Ω be a 2-dimensional bounded domain, symmetric with respect to the x2-axis. The boundary has several connected components, intersecting the x2-axis. The boundary value is symmetric with respect to the x2-axis satisfying the general outflow condition. The existence of the symmetric solution to the steady Navier–Stokes equations
was established by Amick [2] and Fujita [4]. Fujita [4] proved a key lemma concerning the solenoidal extension of the boundary
value by virtual drain method. In this note, we give a different proof via elementary approach by means of the stream function. 相似文献