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991.
Dr. Yuki Sakamoto Dr. Toru Amaya Dr. Takeyuki Suzuki Prof. Dr. Toshikazu Hirao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(52):18686-18689
The PdII‐catalyzed dehydroboration of boron enolates generated from ketones and 9‐iodo‐9‐borabicyclo[3.3.1]nonane was achieved, providing a synthetically versatile protocol from ketones to α,β‐unsaturated ketones. The PdII compound employed in this reaction worked catalytically in the presence of Cu(OAc)2. The high trans‐selectivity of the olefinic moiety was observed. Aryl halide moieties (‐Br and ‐Cl) remained intact for this reaction in spite of the presence of a Pd species. An ester substrate could also be applied when a stoichiometric amount of PdII was used. The crossover reactions using boron and silyl enolates revealed that the oxidation reaction is much faster than the Saegusa‐Ito reaction. 相似文献
992.
993.
Yosuke Kuriyama Dr. Yuji Kikukawa Dr. Kosuke Suzuki Dr. Kazuya Yamaguchi Prof. Dr. Noritaka Mizuno 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(12):3962-3966
Although stimuli‐responsive structural transformations of inorganic materials have attracted considerable attention because of their potential use as functional switchable materials, multinuclear metal cores frequently suffer from unexpected dissociation of metal cations and/or irreversible transformations into infinite structures. In this study, we describe the successful demonstration of the water‐ and temperature‐triggered reversible structural transformation between cubane‐ and planar‐type tetranuclear CoII cores sandwiched by polyoxometalates. The arrangements and coordination geometries of the CoII cations were interconverted by simple hydration and dehydration, resulting in the manipulation of the magnetic and optical properties of these compounds. Moreover, this system showed unique thermochromism through temperature‐dependent reversible structural interconversion. 相似文献
994.
Akinobu Matsumoto Dr. Mitsuharu Suzuki Dr. Hironobu Hayashi Dr. Daiki Kuzuhara Dr. Junpei Yuasa Prof. Dr. Tsuyoshi Kawai Prof. Dr. Naoki Aratani Prof. Dr. Hiroko Yamada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(41):14462-14466
We prepared perylene dications 1 2+ and 2 2+ by using “capped” perylene derivatives, and for the first time, successfully obtained single crystals of a perylene dication 1 2+ that enabled us to perform its structural analysis. We realized that the substituted aryl groups on perylene control the positions of positive charges, thus the remaining electronic system satisfies Clar's sextet rule toward the highest number of localized sextets. Experimental and theoretical evidence proved that Clar's aromatic π‐sextet rule could be applied even for the dicationic perylenes in a very simple way. 相似文献
995.
996.
The relative gamma-ray intensities in the energy region between 122 and 411 keV in the decay of152Eu were measured by using a Ge(Li) detector. Its efficiency calibration was carried out with the radioactive sources of241Am,57Co,203Hg,137Cs,133Ba,75Se,169Yb and192Ir. 相似文献
997.
T. Tanaka A. Hazato K. Bannai N. Okamura S. Sugiura K. Manabe S. Kurozumi M. Suzuki R. Noyori 《Tetrahedron letters》1984,25(43):4947-4950
6-Oxoprostaglandin E1 methyl ester was synthesized in a single pot from ()-4--butyldimethylsiloxy-2-cyclopentenone by organocopper conjugate addition with an ω side-chain unit, trapping of the resulting enolate with 6-methoxycarbonyl-2-nitrohex-1-ene, and treatment with aqueous titanium(III) trichloride. Hydrolysis of the methyl ester was accomplished by porcine liver esterase. 6-Oxoprostaglandin F1α, was obtained from 6-nitroprostaglandin E1 methyl ester in four steps. 相似文献
998.
999.
H Kimata K Nakajima H Suzuki T Koide S Yamamoto T Narita 《Chemical & pharmaceutical bulletin》1991,39(12):3327-3330
To study the thrombolytic effect of tissue plasminogen activator (t-PA) on cerebral emboli, we characterized cerebral embolization in stroke-prone spontaneously hypertensive rats (SHRSPs) and Wistar Kyoto rats (WKYs). [125I]Fibrin clot particles (20-100 microns diameter) were injected twice at an interval of 90 min into the left internal carotid artery of WKYs and SHRSPs. After each injection, spontaneous embolus dissolution was monitored with a gamma-ray detector placed on the head of the embolic rats. Embolus dissolution was spontaneously generated in 15 min after the injection of fibrin clots. In WKYs, 21% and 42% of the clots were dissolved 30 and 90 min after the second embolization, respectively. On the other hand, the spontaneous embolus dissolution in SHRSPs was significantly lower than that of WKYs, indicating that the endogenous fibrinolytic ability of SHRSPs is less potent than that of normotensive rats. The intravenous administration of t-PA at doses of 75, 250 and 750 micrograms/kg caused a dose-dependent embolus dissolution in SHRSPs. Furthermore, systematically applied t-PA produced embolus dissolution without causing systemic plasminogen activation, fibrinogen breakdown or bleeding. In conclusion, the intravenous administration of t-PA produces selective embolus dissolution without systemic fibrino(geno)lysis in a cerebral embolic SHRSP. 相似文献
1000.
K Watanabe K Tohda H Sugimoto F Eitoku H Inoue K Suzuki S Nakamura 《Journal of chromatography. A》1991,566(1):109-116
An ion-sensitive field effect transistor, which is a small potentiometric ion-sensing probe, was applied as a detector in the ion chromatography of alkali-metal cations. The cation-sensing transistor was prepared by coating the gate part of the probe to form a poly(vinyl chloride) matrix membrane containing tetranactin, which enables detection of alkali-metal ions such as Na+, K+, Rb+, and Cs+. To be able to analyse amounts less than 1 microliter and make full use of the small ion-sensing probe, we constructed a miniature cation-exchange separation column (support 10 microns polystyrene) with a PTFE tube (20 mm x 1.5 mm I.D. x 2.1 mm O.D). As an application of the system, Na+ and K+ concentrations in serum were determined. The analytical results for these two cations were good agreement with those obtained by flame photometry. 相似文献