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141.
Tomohisa Nagamatsu Yoshiji Hantani Minoru Yamada Kenji Sasaki Hiromi Ohtomo Taiji Nakayama Takashi Hirota 《Journal of heterocyclic chemistry》1993,30(1):193-202
As a series of polyheterocyclic compounds for exploitation as anti-platelet agents, tricyclic heterocyclic compounds, 4-substituted 6,7-dihydro-5H-pyrimido[5,4-d][1]benzazepines 3–6, 9, 12–14 , and 16–26 , having nitrogen, oxygen, or sulfur containing functional groups at the 4-position, were prepared. In addition, tetra-cyclic heterocyclic compounds, 3-methyl-1,2,5,6-tetrahydro-4H-imidazo[1′,2′:1,6]pyrimido[5,4-d][1]benzaze-pinium chloride ( 7 ), 1,2,5,6-tetrahydro-4H-imidazo[1′,2′:1,6]pyrimido[5,4-d][1]benzazepines 10a-e , 2,3,6,7-tetrahydro-1H 5H-pyrimido[1′,2′:1,6]pyrimido[5,4-d][1]benzazepine ( 11 ), and 1,2,5,6-tetrahydro-4H-thiazolo-[3′,2′:1,6]pyrimido[5,4-d][1]benzazepinium chloride ( 15 ) via ring closure of 4-(hydroxyalkylamino)- 6, 9a-e , and 3c , and 4-(2-hydroxyethylthio)-6,7-dihydro-5H-pyrimido[5,4-d][1]benzazepine ( 14 ) with phosphoryl chloride or thionyl chloride, respectively, were also prepared. Their inhibitory activities against collagen-induced aggregation of rabbit blood platelets in vitro were investigated. Among them, compound 5 having a morpholino group at the 4-position on the tricyclic nucleus, which enhanced the activity more than 14-fold as compared with aspirin, was found to have the most satisfactory in inhibitory activity. 相似文献
142.
H Oka Y Ikai N Kawamura K Uno M Yamada K Harada M Uchiyama H Asukabe Y Mori M Suzuki 《Journal of chromatography. A》1987,389(2):417-426
A simple, rapid and precise analytical method for the residual tetracyclines in honey has been established using a tandem cartridge clean-up system (prepacked reversed-phase and ion-exchange cartridges) followed by high-performance liquid chromatography. The recoveries of oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC) and doxycycline (DC) from honey spiked at a level of 1.0 ppm are 87.1, 85.3, 98.0 and 99.0%, respectively, with coefficients of variation of 1.1-3.9%. The detection limits in honey are 0.02 ppm for OTC and TC, and 0.05 ppm for CTC and DC, respectively. The time required for the analysis of four samples is only 1 h. 相似文献
143.
Akutsu H Akutsu-Sato A Turner SS Day P Canadell E Firth S Clark RJ Yamada J Nakatsuji S 《Chemical communications (Cambridge, England)》2004,(1):18-19
Three conducting BEDT-TTF charge-transfer salts with tris(oxalato)metallate anions have unit cells containing both[small alpha] and [small beta][double prime] donor packing motifs. 相似文献
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148.
Kenzo Miyazaki Toru Fukatsu Ichiro Yamashita Toshifumi Hasama Kawakatsu Yamada Takuzo Sato 《Applied physics. B, Lasers and optics》1991,52(1):1-7
Improvements in output pulse energy and efficiency of a conventional capacitor-transfer-type discharge excimer laser with automatic preionization have been achieved by extending the discharge volume and resulting moderate pumping of the active medium. The discharge laser produces a pulse energy of more than 1 J for XeCl, KrF, and ArF lasers in square beams of about 2×2 cm2, and the maximum overall efficiency observed is 2.9% for XeCl, 3.2% for KrF and 1.8% for ArF. The laser device has been involved in a picosecond ( 32 ps) XeCl laser amplification system, and was operated as an amplifier at a repetitive frequency of 10 Hz. Saturation fluence for XeCl laser was measured to be 1.4 mJ/cm2, and the picosecond pulse energy of 40 mJ was extracted from the amplifier.On leave from Ebara Corp., 6-6-7, Ginza, Chuo-ku, Tokyo 104, JapanOn leave from Mitsubishi Heavy Industries, LTD., 4-6-22, Kan-on shinmachi, Nishi-ku, Hiroshima 733, Japan 相似文献
149.
Mori M Oyama Y Suzuki A Takahashi K Yamada M Miyano K Miyata H Takei H Hirata KS Kajita T Kihara K Nakahata M Nakamura K Ohara S Sato N Suzuki Y Totsuka Y Yaginuma Y Koshiba M Suda T Tajima T Fukuda Y Nagashima Y Takita M Kaneyuki K Tanimori T Beier EW Frank ED Frati W Kim SB Mann AK Newcomer FM Van Berg R Zhang W 《Physical review D: Particles and fields》1991,43(9):2843-2846
150.
H. Etori H. Hirata Y. Yamada H. Okabayashi M. Furusaka 《Colloid and polymer science》1997,275(3):263-273
Potassium salts of N-decanoylglycine and N-decanoyl-L-alanine oligopeptides (monomer, dimer and trimer) were synthesized.
For these oligomer salts in aqueous solutions, the microstructures of micelles have been investigated by small-angle neutron-scattering
(SANS). In the calculation of SANS intensity data, the thickness of the hydrophilic layer was altered by changing the conformation
of the oligomer moiety (helical and β-sheet structures). For micelles of the trimer salts, the helical structure models provide
the best fit to the observed SANS intensity data. For micelles of the monomer-and dimer-salts, the β-sheet model provides
the best fit to the observed data. For the monomer-and dimer-micelles, the aggregation number (n) is not dependent on the species of amino acid residue, imply-ing that the decanoyl group plays a critical role in micelle
formation. However, for the trimer micelles, the n value is dependent on the species of amino acid residue.
Received: 11 July 1996 Accepted: 11 September 1996 相似文献