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Methyl (3,6-dichloropyridazin-4-yl)acetate (II), prepared from methyl (3,6-dihydroxypyrid-azin-4-yl)aeetate (1) by chlurination with phosphorus oxychloride, was used for studies of nucleo-philic displacement reactions and it has been found that only the chlorine atom at position 6 was displaced with hydrazine. With diluted hydrochloric acid both chlorine atoms were displaced with the 6-oxo isomer predominating. By turning the aromatic ring of pyridazine into an o-quinoid system, the chlorine atom at position 3 became mobile. Cyelization of (6-hydrazino-s-triazolo-[4,3-b ]pyridazin-7-yl)acetic acid hydrazide (XIX) gave 6-aminopyrrolo[3,2-e ]s-triazlo[ 4,3-b ]-pyridazm-7(8H)one (XXI). 相似文献
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Maria Siołek 《International Journal of Polymer Analysis and Characterization》2014,19(3):222-233
The reactivity ratios of four butyl acrylates versus methyl methacrylate and tert-butyl methacrylate were determined for their radical copolymerization in 2-butanone solution using the Jaacks method. The reactivity ratios values obtained were positively verified by substituting into the Alfrey-Goldfinger equation, yielding correct copolymer composition for a series of samples obtained from different initial mole fractions of the comonomers. 相似文献
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A novel option pricing method based on Fourier-cosine series expansion was proposed by Fang and Oosterlee. Developing their idea, three new option pricing methods based on Fourier, Fourier-cosine and Fourier-sine series expansions are presented in this paper, which are more efficient when the option prices are calculated with many strike prices. A series of numerical experiments under different exp-L~vy models are also given to compare these new methods with the Fang and Oosterlee's method and other methods. 相似文献
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P. Sarti-Fantoni D. Donati F. De Sio G. Moneti 《Journal of heterocyclic chemistry》1980,17(7):1643-1644
The use of enriched Na18OH in the hydrolysis of 3-methyl-4-nitro-5-styrylisoxazole leads to oxygen-labelled cinnamic acids. Isoxazole ring opening and cleavage of title compound has been investigated. 相似文献
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Rodolfo Nesi Stefano Chimichi Francesco De Sio Roberto Pepino Piero Tedeschi 《Tetrahedron letters》1982,23(42):4397-4400
In contrast with a previous report, permanganate oxidation of the title compound gives the nitroisoxazolone and not 3-methyl-4- nitroisoxazole-5-carboxylic acid ; a reaction pathway, involving the spirocyclisation of the carboxylate , is suggested. 相似文献
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A 13C nmr study of a diazo, of two diazonium salts and of some other model pyrazole compounds is reported. It is found that the C-4 diazo carbon is more shielded than the normal sp2 pyrazole hybridized carbon, while its diazonium salt is more deshielded. The electron density on the C-4 of the diazopyrazole is probably due to the positive charge on the terminal nitrogen. Thus the 13C chemical shift values allowed us to understand the chemical behaviour of a compound of potential antitumor activity. 相似文献
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We investigate nonlinear oscillations in a fourth-order partialdifferential equation which models a suspension bridge. Previouswork establishes multiple periodic solutions when a parameterexceeds a certain eigenvalue. In this paper, we use Leray-Schauderdegree theory to prove that if the parameter is increased further,beyond a second eigenvalue, then additional solutions are created. 相似文献
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S. Chimichi F. De Sio D. Donati R. Pepino L. Rabatti P. Sarti-Fantoni 《Journal of heterocyclic chemistry》1983,20(1):105-107
The vic-dibromo derivatives obtained by bromine addition to 3-methyl-4-nitro-5-styrylisoxazoles were used as starting materials for the preparation of arylpropiolic acids. 相似文献