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71.
T Kawakita T Kuroita M Yasumoto M Sano K Inaba T Fukuda T Tahara 《Chemical & pharmaceutical bulletin》1992,40(3):624-630
A series of 3,4-dihydro-3-oxo-1,4-benzoxazine-8-carboxamide derivatives was synthesized and evaluated for serotonin-3 (5-HT3) receptor antagonistic activity assessed by their ability to antagonize the von Bezold-Jarish (BJ) effect in rats. Derivatives bearing 1-azabicyclo[2.2.2]oct-3-yl moiety as a basic function attached to the carboxamide at position 8 showed more potent antagonistic activity than those bearing the other three basic moieties. Structure-activity relationships of this series showed that methyl and chloro groups were more effective as substituents at positions 4 and 6, respectively. The representative compound 15 (Y-25130) in this series showed potent antagonistic activity on the BJ effect (ED50 = 1.3 micrograms/kg i.v.), high affinity for 5-HT3 receptor (Ki = 2.9 nM) and complete protection against cisplatin-induced emesis in dogs at a dose of 0.1 mg/kg i.v. 相似文献
72.
In the presence of CuCN, reaction of γ,γ-dialkoxyallylic zirconium species 1 with imines proceeded at the γ-position of 1 to give gem-dialkoxyhomoallylic amines 3 in high yield. In this reaction, γ,γ-dialkoxyallylic zirconium species 1 acts as an α,β-unsaturated acyl anion equivalent. 相似文献
73.
Carbon dioxide fixation by microalgae photosynthesis using actual flue gas discharged from a boiler 总被引:2,自引:0,他引:2
Matsumoto Hiroyo Shioji Norio Hamasaki Akihiro Ikuta Yoshiaki Fukuda Yoshinori Sato Minoru Endo Noriyoshi Tsukamoto Toshiaki 《Applied biochemistry and biotechnology》1995,(1):681-692
To mitigate CO2 discharged from thermal power plants, studies on CO2 fixation by the photosynthesis of microalgae using actual exhaust gas have been carried out. The results are as follows.
相似文献
1. | A method is proposed for evaluating the maximum photosynthesis rate in the raceway cultivator using only the algal physical properties; |
2. | Outdoor cultivation tests taking actual flue gas were performed with no trouble or break throughout 1 yr using the strain collected in the test; |
3. | The produced microalgae is effective as solid fuel; and |
4. | The feasibility studies of this system were performed. The system required large land area, but the area is smaller than that required for other biomass systems, such as tree farms. |
74.
Ohsaka T Tian Y Shioda M Kasahara S Okajima T 《Chemical communications (Cambridge, England)》2002,(9):990-991
A superoxide dismutase (SOD)-modified electrode, in which SOD is oriented on the gold electrode via a self-assembled monolayer of cysteine so as to allow its direct electrode reaction, possesses a bi-directional electrocatalysis for both the oxidation of superoxide ion (O2-) to O2 and the reduction of O2- to H2O2 and functions as a third generation O2- biosensor. 相似文献
75.
Oku K Watanabe H Kubota M Fukuda S Kurimoto M Tsujisaka Y Komori M Inoue Y Sakurai M 《Journal of the American Chemical Society》2003,125(42):12739-12748
Trehalose is a disaccharide that attracts much attention as a stress protectant. In this study, we investigated the mechanism of the antioxidant function of trehalose. The spin-lattice relaxation times (T(1)) of (1)H and (13)C NMR spectra were measured to investigate the interaction between trehalose and unsaturated fatty acid (UFA). We selected several kinds of UFA that differ in the number of double bonds and in their configurations (cis or trans). Several other disaccharides (sucrose, maltose, neotrehalose, maltitol, and sorbitol) were also analyzed by NMR. The T(1) values for the (1)H and (13)C signals assigned to the olefin double bonds in UFA decrease with increasing concentration of trehalose and the changes reaches plateaus at integer ratios of trehalose to UFA. The characteristic T(1) change is observed only for the combination of trehalose and UFA with cis double bond(s). On the other hand, from the (13)C-T(1) measurements for trehalose, the T(1) values of the C-3 (C-3') and C-6' (C-6) are found to change remarkably by addition of UFA. (1)H[bond](1)H NOESY measurements provide direct evidence for complexation of trehalose with linoleic acid. These results indicate that one trehalose molecule stoichiometrically interacts with one cis-olefin double bond of UFA. Computer modeling study indicates that trehalose forms a stable complex with an olefin double bond through OH...pi and CH...O types of hydrogen bonding. Furthermore, a significant increase in the activation energy is found for hydrogen abstraction reaction from the methylene group located between the double bonds that are both interacting with the trehalose molecules. Therefore, trehalose has a significant depression effect on the oxidation of UFA through the weak interaction with the double bond(s). This is the first study to elucidate the antioxidant function of trehalose. 相似文献
76.
The unstable species aminoborane, BH2NH2, has been identified as a reaction product of ammonia with diborane by microwave spectroscopy. The rotational constants determined are A = 138212 ± 4 MHz, B = 27487.83 ± 0.10 MHz and C = 22878.44 ± 0.11 MHz for 11BH2NH2 and A = 138199 ± 6 MHz, B = 28420.36 ± 0.11 MHz and C = 23520.78 ± 0.12 MHz for 10BH2NH2. The dipole moment is 1.844 ± 0.015 D. 相似文献
77.
Koji Yagi Veronica Garcia Ma. E. Rivas Javier Salas Andres Camargo Takeo Tabata 《Journal of inclusion phenomena and macrocyclic chemistry》1984,2(1-2):179-184
Some crown ethers were found to show significant antifungal activity against some wood-decay fungi, phytopathogenic fungi and eumycetes,Trichophytons for dermatomycosis. Their toxicity was evaluated by the paper disc method as well as by determining the values of ED50, i.e., the concentration which inhibits the mycelium growth by 50%. The fungi examined areTyromyces palustris, Picnoporous coccineus, Coriolous versicolor, Pyricularia filamentosa, Fusarium sp., Trichophyton rubrum, Trichophyton sp., etc. Among the 26 crown ethers tested, 3,5-di-t-butyl-benzo-15-crown-5 showed relatively high activity, the highest ED50 value of which being 8 M or 3 ppm. Other alkylbenzocrown ethers, dicyclohexyl crown ethers and Kryptofix 22DD also showed considerable activity. On the other hand, unsubstituted crown ethers, benzocrown ethers with a polar substituent, Kryptofix 222B and Kryptofix 221 were inactive. 相似文献
78.
Takeo Araki Shuzi Hayase Akira Nakamura 《Journal of polymer science. Part A, Polymer chemistry》1983,21(6):1671-1679
Based on our recent discovery of the isomerization polymerization of β-(2-acetoxyethyl)-β-propiolactone into poly-δ-ester,1,2 we examined the generality of this phenomenon by using two related monomers. The catalysts were (EtAlO)n and Et(ZnO)2ZnEt. The side-chains in the monomers selected were the (CH3)2CHCOO? CH2CH2? (2) and (CH3)CICHCOO? CH2CH2? (3) groups in which steric effects are almost identical but electronic effects are in opposition. The monomers yielded isomerized poly-δ-ester units, depending on the terminal substituent groups in the side-chain. These observations can be interpreted with the bicyclic intermediate proposed in the earlier work. Monomer (2) was reactive and produced a poly-δ-ester structure most readily, probably because of the higher electron density at the side-chain ester group which coordinated with the catalyst. In contrast, monomer (3) was less reactive, and the probability of isomerization was the lowest, i.e., the electron deficient side-chain ester group apparently interfered with the formation of the intermediate, especially in the Zn-catalysis. Equibinary random copolymers were prepared from (2) and (3) according to the catalyst and polymerization conditions chosen. 相似文献
79.
N-(omega-Bromoalkyl)-amino acid derivatives, readily prepared from natural alpha-amino acids, gave cyclic amino acids with a quaternary stereocenter by treatment with potassium hexamethyldisilazaide in DMF. The chirality of parent amino acids was almost completely preserved during an enolate-formation and cyclization process, giving aza-cyclic amino acids in up to 98% ee in retention of configuration. This method is applicable to the asymmetric synthesis of azetidine, pyrrolidine, piperidine, and azepane derivatives. The asymmetric cyclization seems to proceed via an axially chiral enolate intermediate and not through a concerted SEi process. 相似文献
80.
The catalyst comprised [PdCl(η3-C3H5)]2 and a simple chiral hemilabile ferrocene ligand, 1′,2-bis(diphenylphosphinoethyl)ferrocenyl alcohol, provides synthetically acceptable results for an enantioselective Pd-catalyzed allylic alkylation of cyclohexanone derivatives bearing an electron-withdrawing group at the α-position to form the quaternary carbon with up to 90% enantioselectivity under mild reaction conditions. 相似文献