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141.
Taketoshi Makino Tetsuji Nunozawa Naomichi Baba Junichi Oda Yuzo Inouye 《Tetrahedron letters》1979,20(19):1683-1686
Asymmetric reduction of α-ketoester with a chiral dihydronicotinamide was significantly affected by chiral aromatic additives, capable of exerting an attractive interaction with dihydropyridine ring, which was further consolidated through with magnesium. 相似文献
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Aggregation behaviors of gemini nucleotide at the air-water interface and in solutions induced by adenine-uracil interaction 总被引:2,自引:0,他引:2
Wang Y Desbat B Manet S Aimé C Labrot T Oda R 《Journal of colloid and interface science》2005,283(2):555-564
Cationic gemini surfactants having nucleotides as counterions (called nucleo-gemini hereafter) were synthesized and their aggregation behavior at air-water surfaces as well as in bulk solutions were studied. Fluid solutions of these nucleo-gemini surfactants show transitions to hydrogels upon addition of complementary nucleoside bases or other nucleo-gemini surfactants having complementary bases as counterions. The FTIR-ATR measurements show that the carboxylate groups of uridine form hydrogen bonds with the amine groups of adenosine. The aggregation behavior was also confirmed at the air-water interface by Brewster angle microscopy as well as surface pressure measurements; the monolayer of a gemini nucleotide was observed to undergo a transition to multilayers when nucleosides with complementary bases were added into the subphase. Isotherm curves of surface pressure monitored in parallel show a decrease in molecular area upon addition of such nucleosides. 相似文献
145.
Edward A. Nodiff Shuichiro Ina Noriichi Oda Takanori Hayazaki Sansei Nishibe Tetsuya Kohno Martin Hausman Albert A. Manian 《Journal of heterocyclic chemistry》1967,4(2):239-245
The title compounds and various derivatives have been prepared as analytical standards for the identification of chlorpromazine metabolites in biological materials. Additional evidence is presented for the existence of a halogen-induced Smiles rearrangement in the phenothiazine series. 相似文献
146.
-Nitrophenylhydrazones, unsusceptible to autoxidation, are readily oxygenated in the presence of a five-coordinate cobalt(II)-Schiff base complex, Co(II)(MeOSalen) (Py) leading to quantitative formation of novel 1-(-nitrophenylazo)-1-peroxy Co(III) complexes 2, which were isolated as crystals. A plausible mechanism involving hydrogen abstraction by Co(III)(O2?.) from the substrate followed by formation of a substrate anion Co(III) complex intermediate is proposed. 相似文献
147.
This paper describes the results of hint-effect experiments, and analyses the human decision-making process from fuzzy-theoretic and concept-formational viewpoints. To begin with, we discuss the problem of the decision-making process subject to a specific and newly given information. In other words, the fuzzy-theoretic experiment concerning with some hints in the estimation and decision processes of the card arrangement is conducted. Next, the concept-formational process is analysed clearly by means of the introduction of both the cusp-curved surface in catastrophe theory and fuzziness concept in fuzzy set theory. Finally, we show the hint effect in the estimation and decision processes. 相似文献
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Three allylbenzenes from Asiasarum heterotropoides, methyleugenol (1), elemicin (2) and gamma-asaron (3) showed suppressive effects on umu gene expression of the SOS response in the Salmonella typhimurium OY1001/1A2 umu test against the mutagen 2-amino-3,4-dimethylimidazo[4,5-f ]quinoline (MeIQ). Gene expression was suppressed 70.0, 75.9 and 81.7% at a concentration of 0.4 mM, respectively. The ID50 values (50% inhibition dose) of these compounds were 0.125, 0.098 and 0.059 mM, respectively. On the other hand, compounds 1-3 showed weak suppressive effects of the SOS-inducing activity on activated MeIQ. 相似文献