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111.
Emile Bisagni Alain Civier Jean-Pierre Marquet 《Journal of heterocyclic chemistry》1975,12(3):461-465
Treatment of 4-hydroxy-6-methylpyran-2-one with chloracetalhyde in basic aqueous medium gave 6-methylfuro[3,2-c]pyran-4-one. This compound reacted with ammonium hydroxide and some primary amines to form the corresponding N-substituted furo[3,2-c]pyrid-4-ones which may also be obtained from 4-hydroxy-α-pyridones. Furo[3,2-c]pyran-4-one was acylated at the 2 position and 4-chloro-6-methylfuro[3,2-c]pyridine easily gave 4-substituted derivatives by displacement of the halogen atom. 相似文献
112.
Christian Rivalle Christiane Huel Emile Bisagni 《Journal of heterocyclic chemistry》1989,26(3):577-580
Starting from 4-chloronicotinic and derivatives and 6-amino-5-methyl-2H-isoquinolin-1-one, subsequent cyclization of intermediates by sulfuric acid or trifluoromethanesulfonic acid and chlorination by phosphorus oxychloride gave 10-chloro-6-methyl-5H-isoquino[6,6-b][1,6]naphthyridin-12-ones. Cytotoxicity of the corresponding 10-(diethylamino-3)propylamino-6-methyl-5H-isoquino[6,7-b][1,6]naphthyridinh12-ones, compared to that of related 9-azaellipticine derivatives, showed that replacement of pyrrole by a pyridin-4-one nucleus resulted in loss of biological activity. 相似文献
113.
Kentaro Okuma Tomoko Ishida Shinya Morita Hiroshi Ohta Tohru Inoue 《Heteroatom Chemistry》1995,6(3):265-270
Metal and temperature effects on thio-Wittig reactions have been studied. Stabilized phosphorus ylides, such as carbomethoxymethylenetriphenylphosphorane, reacted with sulfur to afford dimethyl maleate and dimethyl fumarate in a 1:4 ratio. As in the case of conventional Wittig reactions with semistabilized ylides, it has been shown that the stereochemistry (E:Z ratio) of alkene formation is determined at the point that a new carbon–carbon bond has been formed to give a thiaphosphetane intermediate. The temperature dependence of this reaction is also discussed. 相似文献
114.
Serge Cosnier Sabine Szunerits Robert S. Marks Andres Novoa Laurence Puech Emile Perez Isabelle Rico-Lattes 《Electrochemistry communications》2000,2(12):3
Novel enzyme electrodes based on synthetic hydrophilic latex matrices are described for the detection of glucose. Glucose oxidase was immobilised through micro-encapsulation, by the simple adsorption of enzyme–latex suspensions on the surface of a platinum electrode. Two latex films functionalised by a hydroxy or a gluconamide group were used. The response of these biosensors to glucose additions was measured by potentiostating the modified electrodes at 0.6 V/SCE in order to oxidise the hydrogen peroxide generated by the enzymatic oxidation of glucose in the presence of dioxygen. The response of such electrodes was evaluated as a function of film thickness and temperature. The sensitivity for a two-layer latex-based biosensor was found to be 38.78 mA M−1 cm−2 with a response time of 3–5 s. Moreover, a marked improvement of the thermal stability of the biosensor was observed. Only at temperatures higher than 65°C the enzyme started to be denatured and being inactive. 相似文献
115.
K. Okuma T. Fujisaki Y. Nakazawa K. Saito M. Oguni 《Journal of Thermal Analysis and Calorimetry》2005,81(3):587-590
Summary We have performed low-temperature heat capacity measurements on pellet samples of (DMe-DCNQI)2M (M=Li, Ag) which is known to show spin-Peierls transitions at 51 and 86 K, respectively. A linearly temperature-dependent term in the low-temperature heat capacity has been observed for both the samples: It is attributable to the spin-wave excitations induced by the inhomogeneous pressure effects produced in the pellet forming process. Although the temperature dependences of the magnetic susceptibility in both materials are almost the same, the coefficient of T-linear term of the Ag salt becomes three times larger that that of the Li salt. The peculiar electronic state originating from the competition of the spin-Peierls mechanism and the Coulomb repulsion is suggested. 相似文献
116.
J. P. Mehlig K. R. Johnson K. Suitsu und K. Okuma 《Fresenius' Journal of Analytical Chemistry》1941,122(3-4):132
Ohne Zusammenfassung 相似文献
117.
Analytical and Bioanalytical Chemistry - 相似文献
118.
119.
Grotenbreg GM Witte MD van Hoof PA Spalburg E Reiss P Noort D de Neeling AJ Koert U van der Marel GA Overkleeft HS Overhand M 《Organic & biomolecular chemistry》2005,3(2):233-238
The design and synthesis of analogues of the cyclic beta-sheet gramicidin S (GS), having additional functionalities in their turn regions, is reported. The monomeric GS analogues were transformed into dimers and their activities towards biological membranes, through antimicriobial and hemolytic assays, were evaluated. Finally, conductivity measurements have been performed to elucidate ion channel forming properties. 相似文献
120.
Thierry Avignon Emile Jean Vincent Jacques Raymond Max Chaillet 《Journal of Molecular Structure》1974,21(2):319-329
The vibrational frequencies of thiazole and its deuterated derivatives have been used in valence force field calculations. The transferability of the force field is verified by the study of 2-chloro- and 2-methyl-thiazole. Previous assignments are discussed. 相似文献