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991.
Nishioka T Kitayama H Breedlove BK Shiomi K Kinoshita I Isobe K 《Inorganic chemistry》2004,43(18):5688-5697
Reaction of trans-[(MCp)(2)(mu-CH(2))(2)Cl(2)] (M = Rh, Ir; Cp = eta(5)-C(5)Me(5)) with Li(2)S(2) afforded the disulfido complexes [(MCp)(2)(mu-CH(2))(2)(mu-S(2)-S:S')] which were easily oxidized by O(2) to give the oxygenated complexes [(MCp)(2)(mu-CH(2))(2)(mu-SSO(2)-S:S')]. Although [(RhCp)(2)(mu-CH(2))(2)(mu-S(2)-S:S')] gave a complicated mixture when reacted with CH(2)Cl(2) or CHCl(3), [(IrCp)(2)(mu-CH(2))(2)(mu-S(2)-S:S')] reacted with both CH(2)Cl(2) and CHCl(3) to give the dithioformato complex [(IrCp)(2)(mu-CH(2))(2)(mu-S(2)CH-S:S')]Cl and the cyclotetrasulfido complex [((IrCp)(2)(mu-CH(2))(2))(2)(mu-S(4)-S:S':S":S"')]Cl(2). The oxygenated complexes [(RhCp)(2)(mu-CH(2))(2)(mu-SSO(2)-S:S')] reacted with hydrocarbyl halides to afford bridging hydrocarbyl thiolato complexes accompanied by the generation of SO(2) gas. These complexes have been characterized by NMR spectroscopy, ESI-MS, and X-ray diffraction. 相似文献
992.
Kan T Hosokawa S Nara S Tamiya H Shirahama H Matsuda F 《The Journal of organic chemistry》2004,69(25):8956-8958
Complete reversal of diastereoselectivity was observed in the SmI(2)-promoted ketyl-olefin coupling cyclizations of the hydroxy ketone or aldehyde and its acetate. For example, the stereodivergent synthesis of the epimeric five-membered-ring alcohols 2 and 4 has been accomplished through the SmI(2)-induced ketyl-olefin coupling cyclizations of the delta-hydroxy ketone 1 and delta-acetoxy ketone 3. 相似文献
993.
994.
Hasobe T Hattori S Kotani H Ohkubo K Hosomizu K Imahori H Kamat PV Fukuzumi S 《Organic letters》2004,6(18):3103-3106
[structure: see text] The photovoltaic cell composed of both fullerene nanoclusters and 9-mesityl-10-carboxymethylacridinium ion exhibits significant enhancement in the photoelectrochemical performance as well as broader photoresponse in the visible and near-infrared regions as compared with the reference system containing only each component. 相似文献
995.
Chambers JJ Gouda H Young DM Kuntz ID England PM 《Journal of the American Chemical Society》2004,126(43):13886-13887
AMPA (alpha-amino-3-hydroxy-5-methyl-4-isooxazole) receptors, a major subtype of ionotropic glutamate receptors (iGluRs), mediate the majority of the fast communication between neurons, and the activity-dependent trafficking of AMPA receptors at synapses plays a role in mammalian learning and memory. Here we describe the design, synthesis, and evaluation of a photoreactive AMPA receptor antagonist that provides a means of "knocking out" AMPA receptors present on the surface of cells. The antagonist, 6-azido-7-nitro-1,4-dihydroquinoxaline-2,3-dione (ANQX), was designed by introducing a photoreactive azido group onto a quinoxalinedione inhibitor scaffold. Computational docking of ANQX to the AMPA receptor ligand-binding core predicted efficient binding to AMPA receptors. Glutamate-evoked currents were reversibly blocked at micromolar ANQX concentrations prior to photolysis and irreversibly blocked following photolysis. ANQX provides a means of directly evaluating the trafficking of native AMPA receptors with unparalleled spatiotemporal resolution. 相似文献
996.
Kamada A Sasaki A Kitazawa N Okabe T Nara K Hamaoka S Araki S Hagiwara H 《Chemical & pharmaceutical bulletin》2004,52(1):79-88
New types of selective estrogen receptor modulators (SERMs) were synthesized and evaluated for their binding affinity and biological effect on reproductive cells. A proposed lead structure (B) was derivatized to provide compounds 30 and 44, which showed good estrogen-receptor binding affinity (K(i) values: 6.3 and 10 nM, respectively), as well as minimal impact on mammary and uterine carcinoma cells. Introduction of an alkyl group in the core structure considerably enhanced receptor-binding affinity of the compounds tested. Synthesis and structure-activity relationships of these compounds are described. 相似文献
997.
Hayashi K Rahman SM Ohno H Tanaka T Toyooka N Nemoto H Hayashi T 《Chemical & pharmaceutical bulletin》2004,52(8):1015-1017
Herpes simplex virus type 1 thymidine kinase (HSV TK) is involved in both antiherpetic therapy and cancer gene therapy with acyclovir (ACV) and ganciclovir (GCV). Enhanced sensitivity to these drugs is advantageous in their clinical use. In the present study, scopadulciol (SDC) and its related compounds were evaluated for their stimulatory effect on the cytotoxicity of ACV and GCV by determination of selective toxicities against HSV TK-expressing HeLa cells. Although SDC remarkably potenciated the cytotoxicity of ACV and GCV, the other tested compounds showed only weak selectivity, except for compound 34. 相似文献
998.
Total reflection total conversion electron yield X-ray absorption fine structure is applied to the evaluation of ion exchange occurring at the surface monolayer of two-tailed ammonium ions. X-ray absorption measurements at a Br K-edge allow us to detect ion-exchange equilibria between Br- and Cl- added in a subphase. The ion-exchange selectivity of Br- over Cl- basically increases as the monolayer is compressed, indicating that Cl- is selectively squeezed out by compression because of its larger hydrated ionic radius. 相似文献
999.
This paper describesin terms of potential-theoretic propertiesthenecessary and sufficient conditions required for a bounded domainsatisfying the capacity density condition to be, respectively:a John domain, a uniform domain and an inner uniform domain.2000 Mathematics Subject Classification 31B05, 31B25. 相似文献
1000.
Liu DW Ashie Y Fukuda S Fukuda Y Ishihara K Itow Y Koshio Y Minamino A Miura M Moriyama S Nakahata M Namba T Nambu R Obayashi Y Sakurai N Shiozawa M Suzuki Y Takeuchi H Takeuchi Y Yamada S Ishitsuka M Kajita T Kaneyuki K Nakayama S Okada A Ooyabu T Saji C Desai S Earl M Kearns E Messier MD Stone JL Sulak LR Walter CW Wang W Barszczak T Casper D Cravens JP Gajewski W Kropp WR Mine S Smy MB Sobel HW Sterner CW Vagins MR Ganezer KS Hill J Keig WE Kim JY Lim IT Ellsworth RW Tasaka S Kibayashi A 《Physical review letters》2004,93(2):021802
A search for a nonzero neutrino magnetic moment has been conducted using 1496 live days of solar neutrino data from Super-Kamiokande-I. Specifically, we searched for distortions to the energy spectrum of recoil electrons arising from magnetic scattering due to a nonzero neutrino magnetic moment. In the absence of a clear signal, we found micro(nu)=(3.6x10(-10))micro(B) at 90% C.L. by fitting to the Super-Kamiokande day-night spectra. The fitting took into account the effect of neutrino oscillation on the shapes of energy spectra. With additional information from other solar neutrino and KamLAND experiments constraining the oscillation region, a limit of micro(nu)=(1.1x10(-10))micro(B) at 90% C.L. was obtained. 相似文献