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71.
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
72.
Hamamoto H Anilkumar G Tohma H Kita Y 《Chemical communications (Cambridge, England)》2002,(5):450-451
A novel and efficient oxidative biaryl coupling reaction of phenol ether derivatives using a combination of hypervalent iodine(III) reagent, phenyliodine(III) bis(trifluoroacetate) (PIFA), and heteropoly acid has been developed. 相似文献
73.
Naozumi Teramoto Toyoki MotoyamaRyutoku Yosomiya Mitsuhiro Shibata 《European Polymer Journal》2002,38(7):1365-1369
Amylose was etherified with 1-bromopropane in DMSO. The degree of substitution (DS) was varied by altering the feed ratio of 1-bromopropane. The structures of the products were characterized by IR and 1H-NMR spectroscopy. When the molar feed ratio of 1-bromopropane to hydroxyl groups of amylose was beyond 7.5, the hydroxyl groups were completely substituted with propyl ether groups. The etherified amylose with DS 1.9 showed a glass transition temperature (Tg), and that with DS 2.3 or 3.0 showed both Tg and melting temperature (Tm) (DS 3.0 means complete substitution). The etherification imparted melt processability and solubility in nonpolar organic solvent to amylose. 相似文献
74.
Alam MS Kim IJ Nemati B O'Neill JJ Romero V Severini H Sun CR Wang P Zoeller MM Crawford G Fulton R Gan KK Kagan H Kass R Lee J Malchow R Morrow F Sung M White C Whitmore J Wilson P Butler F Fu X Kalbfleisch G Lambrecht M Skubic P Snow J Bortoletto D Brown DN Dominick J McIlwain RL Miao T Miller DH Modesitt M Schaffner SF Shibata EI Shipsey IP Battle M Ernst J Kroha H Roberts S Sparks K Thorndike EH Wang C Artuso M Goldberg M Haupt T Horwitz N Kennett R Moneti GC Playfer S Rozen Y Rubin P 《Physical review D: Particles and fields》1992,46(11):4822-4827
75.
76.
Fulton R Jensen T Johnson DR Kagan H Kass R Morrow F Whitmore J Wilson P Bortoletto D Chen W Dominick J McIlwain RL Miller DH Ng CR Schaffner SF Shibata EI Shipsey IP Yao W Battle M Sparks K Thorndike EH Wang C Alam MS Kim IJ Li WC Romero V Sun CR Wang P Zoeller MM Goldberg M Haupt T Horwitz N Jain V Mestayer MD Moneti GC Rozen Y Rubin P Sharma V Skwarnicki T Thulasidas M Zhu G Csorna SE Letson T Alexander J Artuso M Bebek C Berkelman K Browder T Cassel DG Cheu E Coffman DM Crawford G DeWire JW 《Physical review D: Particles and fields》1991,43(3):651-663
77.
Kubota Y Nelson JK Perticone D Poling R Schrenk S Crawford G Fulton R Jensen T Johnson DR Kagan H Kass R Malchow R Morrow F Whitmore J Wilson P Bortoletto D Brown D Dominick J McIlwain RL Miller DH Modesitt M Ng CR Schaffner SF Shibata EI Shipsey IP Battle M Kroha H Sparks K Thorndike EH Wang C Alam MS Kim IJ Li WC Nemati B Romero V Sun CR Wang P Zoeller MM Goldberg M Haupt T Horwitz N Jain V Mestayer MD Moneti GC Rozen Y Rubin P Skwarnicki T Stone S Thusalidas M Yao W Zhu G Barnes AV Bartelt J 《Physical review D: Particles and fields》1991,44(3):593-600
78.
High concentrations of arsenic were observed in the blubber of ringed seals (Pusa hispida) in our previous study. To better understand the arsenic accumulation in blubber of marine mammals, arsenicals in the blubber of ringed seal were characterized using high performance liquid chromatography–inductively coupled plasma mass spectrometry (HPLC–ICPMS). The most predominant water-soluble arsenical in the blubber was dimethylarsinic acid (DMA), in spite of the predominance of arsenobetaine in other tissues. Lipid-soluble fraction was hydrolyzed under mild (tetraethylammonium hydroxide (TEAH) hydrolysis) and strong (NaOH hydrolysis) conditions, and then an aliquot of hydrolysate was injected onto HPLC–ICPMS. Both TEAH-labile and TEAH-stable/NaOH-labile lipid-soluble fractions contained precursors of DMA. These results suggest that the blubber might be the pool of DMA and DMA-containing precursors in ringed seals. 相似文献
79.
Four new iridoid glycosides, named L-phenylalaninosecologanin (1), 7-O-(4-beta-D-glucopyranosyloxy-3-methoxybenzoyl)secologanolic acid (2), 6'-O-(7alpha-hydroxyswerosyloxy)loganin (3) and (Z)-aldosecologanin (5), were isolated, together with a known one, newly named (E)-aldosecologanin (4), from the stems and leaves of Lonicera japonica. Their structures were established on the basis of chemical and spectral data. 相似文献
80.
We have employed a cinchona alkaloid/Selectfluor-mediated enantioselective fluorination of the oxindole 2 to achieve the first enantioslective synthesis of BMS-204352 (MaxiPost, S-1), an effective opener of maxi-K channels. Fluorination occurred to produce S-1 with 84% ee using the bis-cinchona alkaloid (DHQ)(2)AQN. Recrystallization produced enantiomerically pure (>99% ee) product. Quinidine-mediated fluorination of 2 gave the (R)-antipode of 1 with 68% ee. 相似文献