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191.
192.
Tobe M Isobe Y Tomizawa H Nagasaki T Aoki M Negishi T Hayashi H 《Chemical & pharmaceutical bulletin》2003,51(9):1109-1112
We investigated the chemical modifications of the nitroquinazoline derivative (1) through the replacement of the NH group at the C(4)-position with several N-alkyl groups to increase the lipophilicity at the C(4)-position. Among them, we found that the N-methyl analogue (5a) showed a 2-fold loss in the inhibitory activity toward tumor necrosis factor-alpha (TNF-alpha) production in vitro as compared with the NH analogue (1); however, 5a exhibited an oral inhibitory activity on TNF-alpha production with an ED50 value of 26 mg/kg, whereas 1 did not. Moreover, the oral bioavailability of 5a was higher than that of 1 (1, F=1%; 5a, F=21%), and the calculated ClogP value for 5a was higher than that for 1. These results suggest that the improved lipophilicity of 5a compared with that of 1 reflects its greater inhibitory activity on TNF-alpha production in vivo as well as oral bioavailability. 相似文献
193.
Hayashi Y Tsuboi W Shoji M Suzuki N 《Journal of the American Chemical Society》2003,125(37):11208-11209
High pressure induced by water-freezing has been successfully applied to the direct catalytic asymmetric-three component List-Barbas-Mannich reaction, in which higher yield and better enantioselectivity can be realized than those from the reaction at room temperature under 0.1 MPa. 相似文献
194.
Hayashi T Ueyama K Tokunaga N Yoshida K 《Journal of the American Chemical Society》2003,125(38):11508-11509
As a new type of chiral ligand, a C2-symmetric norbornadiene derivative (1R,4R)-2,5-dibenzylbicyclo[2.2.1]hepta-2,5-diene (1) was prepared and used for the rhodium-catalyzed asymmetric addition of organoboron and -tin reagents to alpha,beta-unsaturated ketones, which gave high yields of the 1,4-addition products with up to 99% enantioselectivity. 相似文献
195.
Sitthithaworn W Kojima N Viroonchatapan E Suh DY Iwanami N Hayashi T Noji M Saito K Niwa Y Sankawa U 《Chemical & pharmaceutical bulletin》2001,49(2):197-202
cDNAs encoding geranylgeranyl diphosphate synthase (GGPPS) of two diterpene-producing plants, Scoparia dulcis and Croton sublyratus, have been isolated using the homology-based polymerase chain reaction (PCR) method. Both clones contained highly conserved aspartate-rich motifs (DDXX(XX)D) and their N-terminal residues exhibited the characteristics of chloroplast targeting sequence. When expressed in Escherichia coli, both the full-length and truncated proteins in which the putative targeting sequence was deleted catalyzed the condensation of farnesyl diphosphate and isopentenyl diphosphate to produce geranylgeranyl diphosphate (GGPP). The structural factors determining the product length in plant GGPPSs were investigated by constructing S. dulcis GGPPS mutants on the basis of sequence comparison with the first aspartate-rich motif (FARM) of plant farnesyl diphosphate synthase. The result indicated that in plant GGPPSs small amino acids, Met and Ser, at the fourth and fifth positions before FARM and Pro and Cys insertion in FARM play essential roles in determination of product length. Further, when a chimeric gene comprised of the putative transit peptide of the S. dulcis GGPPS gene and a green fluorescent protein was introduced into Arabidopsis leaves by particle gun bombardment, the chimeric protein was localized in chloroplasts, indicating that the cloned S. dulcis GGPPS is a chloroplast protein. 相似文献
196.
Preeprame S Hayashi K Lee JB Sankawa U Hayashi T 《Chemical & pharmaceutical bulletin》2001,49(4):484-485
A novel fucan sulfate (Hor-1) was isolated from the hot water extract of an edible brown alga, Sargassum horneri (Turner) C. Agardh. The fucan sulfate was revealed to have sugar linkage types, sulfate content and uronic acid content different from those of sodium hornan (Na-HOR), another fucan sulfate isolated from this alga. However, it exhibited inhibitory activity against replication of herpes simplex virus type 1 with similar potency to Na-HOR. 相似文献
197.
Abe K Abe K Adachi I Ahn BS Aihara H Akatsu M Alimonti G Aoki K Asai K Asai M Asano Y Aso T Aulchenko V Aushev T Bakich AM Banas E Behari S Behera PK Beiline D Bondar A Bozek A Browder TE Casey BC Chang P Chao Y Cheon BG Choi SK Choi Y Doi Y Dragic J Eidelman S Enari Y Enomoto R Everton CW Fang F Fujii H Fujita Y Fukunaga C Fukushima M Garmash A Gordon A Gotow K Guler H Guo R Haba J Haji T Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC Hayashi K Hayashii H Hazumi M Heenan EM Higuchi I 《Physical review letters》2001,86(15):3228-3232
We report a determination of the B(0)(d)-&B_(0)(d) mixing parameter Deltam(d) based on the time evolution of dilepton yields in Upsilon(4S) decays. The measurement is based on a 5.9 fb(-1) data sample collected by the Belle detector at KEKB. The proper-time difference distributions for same-sign and opposite-sign dilepton events are simultaneously fitted to an expression containing Deltam(d) as a free parameter. Using both muons and electrons, we obtain Deltam(d) = 0.463+/-0.008 (stat)+/-0.016 (syst) ps(-1). This is the first determination of Deltam(d) from time evolution measurements at the Upsilon(4S). We also place limits on possible CPT violations. 相似文献
198.
Narihara K Watanabe KY Yamada I Morisaki T Tanaka K Sakakibara S Ida K Sakamoto R Ohyabu N Ashikawa N Emoto M Funaba H Goto M Hayashi H Idei H Ikeda K Inagaki S Inoue N Kaneko O Kawahata K Kobuchi T Komori A Kubo S Kumazawa R Masuzaki S Miyazawa J Morita S Motojima O Murakami S Muto S Mutoh T Nagayama Y Nakamura Y Nakanishi H Nishimura K Noda N Notake T Ohdachi S Oka Y Ohkubo K Osakabe M Ozaki S Peterson BJ Sagara A Saito K Sasao H Sasao M Sato K Sato M Seki T Shimozuma T Shoji C Sudo S 《Physical review letters》2001,87(13):135002
It was observed that the vacuum magnetic island produced by an external error magnetic field in the large helical device shrank in the presence of plasma. This was evidenced by the disappearance of flat regions in the electron temperature profile obtained by Thomson scattering. This island behavior depended on the magnetic configuration in which the plasmas were produced. 相似文献
199.
Abe K Abe K Abe R Adachi I Ahn BS Aihara H Akatsu M Alimonti G Asai K Asai M Asano Y Aso T Aulchenko V Aushev T Bakich AM Banas E Behari S Behera PK Beiline D Bondar A Bozek A Browder TE Casey BC Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Dong LY Dragic J Drutskoy A Eidelman S Eiges V Enari Y Enomoto R Everton CW Fang F Fujii H Fukunaga C Fukushima M Gabyshev N Garmash A Gershon TJ Gordon A Gotow K Guler H Guo R Haba J Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC 《Physical review letters》2001,87(9):091802
We present a measurement of the standard model CP violation parameter sin2 phi(1) based on a 29.1 fb(-1) data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. One neutral B meson is fully reconstructed as a J/psi K(S), psi(2S)K(S), chi(c1)K(S), eta(c)K(S), J/psi K(L), or J/psi K(*0) decay and the flavor of the accompanying B meson is identified from its decay products. From the asymmetry in the distribution of the time intervals between the two B meson decay points, we determine sin2 phi(1) = 0.99+/-0.14(stat)+/-0.06(syst). We conclude that we have observed CP violation in the neutral B meson system. 相似文献
200.
Doke T Hayashi T Kikuchi J Sakaguchi T Terasawa K Yoshihira E Nagaoka S Nakano T Takahashi S 《Radiation measurements》2001,33(3):373-387
Dosimetric measurements on the Space Shuttle Missions STS-84, -89 and -91 have been made by the real-time radiation monitoring device III (RRMD-III). Simultaneously, another dosimetry measurement was made by the Dosimetry Telescope (DOSTEL) on STS-84 and by the tissue-equivalent proportional counter (TEPC) on STS-91. First, the RRMD-III instrument is described in detail and its results summarized. Then, the results of DOSTEL and TEPC are compared with those of the RRMD-III. Also, the absorbed doses obtained by TLD (Mg2SiO4) and by RRMD-III on board STS-84 and -91 are compared. 相似文献