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11.
Nishida H Miyazaki Y Kitamura Y Ohashi M Matsusue T Okamoto A Hosaka Y Ohnishi S Mochizuki H 《Chemical & pharmaceutical bulletin》2001,49(10):1237-1244
Intravascular clot formation is an important factor in a number of cardiovascular diseases. Therefore, the prevention of blood coagulation has become a major target for new therapeutic agents. One attractive approach is the inhibition of factor Xa (FXa), which is a key enzyme in coagulation cascade responsible for the generation of thrombin by limited proteolysis of its zymogen, prothrombin. We have investigated 1-arylsulfonyl-3-piperazinone derivatives, containing a 4-(piperidino)pyridine group in place of guanidino and/or amidino groups, and discovered compound M55113 (30a: 4-[(6-Chloro-2-naphthalenyl)sulfonyl]-1-[[1-(4-pyridinyl)-4-piperidinyl]methyl]piperazinone), as a potent inhibitor of FXa (IC50=0.06 microM) with high selectivity for FXa over trypsin and thrombin. 相似文献
12.
Mamiko Odoko Kyouta Yamamoto Nobuo Okabe 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):m469-m470
In the title compound, [Ca(C6H5O4)2(C6H6O4)2]·4H2O, which is a kojic acid–Ca2+ complex, the Ca atom is on a twofold axis and is octacoordinated by O atoms from four pyrone ligand molecules. The hydroxyl and ketone O atoms of each ligand form a five‐membered chelate ring with the Ca atom. The crystal structure is stabilized by partial stacking and O—H?O hydrogen bonds. 相似文献
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Nishimiya N Yamaguchi Y Ohrui Y Suzuki M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(3):493-504
The mirror gap of a Fabry-Perot interferometer was stabilized with two laser diodes; one locked to the line frequency 385,243,555.14445 MHz of the F=3<--1 in 5D(3/2)<--5S(1/2) (87Rb) and the other to the 385,284,566.3663 MHz of the F=4<--2 in 5D(5/2)<--5S(1/2) (87Rb) [Opt. Commun. 102 (1993) 432]. The length of the mirror gap was adjusted to generate the zero-cross points simultaneously at both of the two line positions. The fringe signals obtained from an interferometer thus stabilized can be used as frequency markers having accuracies of the order of 10(10) depending on the finesse of the interferometer used. Based on measurement using Cs D1 hyperfine lines reported by Udem et al. [Phys. Rev. Lett. 82 (1999) 3568], the uncertainty of markers in the region 50 THz apart from the reference lines is +/- 5 MHz. 相似文献
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Polychlorinated biphenyls (PCBs) and chlorobenzenes (CBzs) are two classes of dioxin precursors formed in municipal solid waste incinerators (MSWIs); they produce negative health effects similar to those of dioxins. Reducing the analytical time required for determining the concentrations of these compounds in MSWIs is important for quickly evaluating their importance and assessing associated health risks. In the present study, water is used as a safe and environmentally friendly solvent in microwave-assisted extraction (MAE) for PCB and CBz analyses. MAE is compared with traditional Soxhlet extraction (SE) to determine the extraction efficiencies. The evaluation of extraction efficiencies shows that MAE has a high extraction efficiency compared with that of SE when water content is lower than 60%. Furthermore, the extraction time and organic solvent consumption are reduced with MAE compared with SE. 相似文献
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Carmenza Duque Masuo Morisaki Nobuo Ikekawa Mikio Shikita 《Tetrahedron letters》1979,20(46):4479-4482
Cholesterol and 20-hydroxycholesterol labelled at C-22 stereospecifically by deuterium were incubated with the enzyme of bovine adrenocortical mitochondria. The results indicated that hydroxylation occurs with retention of the configuration of C-22 to give exclusively the 22R stereoisomers of 22-hydroxy- and/or 20,22-dihydroxycholesterol. 相似文献
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Dimethyl and diethyl fluoromalonates were prepared from hexafluoropropene by its exhaustive alcoholysis or alternatively its ammonolysis and alcoholysis. Fluoromalonates thus obtained or their alkylated derivatives were condensed with o-phenylenediamine or its substituted derivatives to give a number of 1H-3-fluoro-1,5-dibenzodiazepin-2,4(3H,5H)-diones. 相似文献
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Yoshimitsu H Nishida M Qian ZZ Lei ZH Nohara T 《Chemical & pharmaceutical bulletin》2000,48(6):828-831
Four new triterpene glycosides were isolated from the dried aerial parts of Thalictrum squarrosum (Ranunculaceae). They were designated as squarroside I, being a cycloartane-type glycoside, and squarrosides II, III and IV, being oleanene-type glycosides. Their structures were established by using two dimensional (2D) NMR techniques. 相似文献