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1.
MM. J. Duflos D. Letouz G. Queguiner P. Pastour 《Journal of heterocyclic chemistry》1973,10(6):1083-1084
This communication describes the synthesis of l-methyl-2,3-diformylpyrrole. This new compound is used to prepare a new heterocycle, l-methylcyclohepta[b]pyrrol-6-one and thus allows a new synthesis of l-methylpyrrolo[2,3-d]pyridazine. 相似文献
2.
L. P. Glushko T. M. Malinovskaya M. S. Malinovskii M. M. Kremlev N. I. Pokhodenko T. A. Zyablikova N. A. Zhikhareva 《Chemistry of Heterocyclic Compounds》1974,10(5):513-515
N,N-Diethylcarbamoyl-4,5-epoxy-2-hexenoic acid reacts with ketones in the presence of anhydrous FeCl3 to give 2,2,4-trialkyl-5-[2-N,N-diethylcarbamoyl(vinylene)]-1,3-dioxolane. 2,2,4-Trimethyl-5-(1-propenyl-3-hydroxy)-1,3-dioxolane is formed in the reduction of 2,2,4-trimethyl-5-[2-carbethoxy(vinylene)]-1,3-dioxolane withlithium aluminum hydride. 相似文献
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A. N. Kremlev 《Numerical Analysis and Applications》2017,10(3):207-223
An exact analytical solution to the eikonal equation for a plane wave refracted on a boundary comprising both convex and concave obtuse angles has been built. Under the convex angle summit the solution has a line of discontinuity in the ray vector field and in the first derivatives of the first arrival times, and under the concave angle it has a cone of waves diffracted on this angle. This cone corresponds to the Keller diffraction cone in the geometric diffraction theory. The relation between the eikonal equation and the resultant Hamilton–Jacoby equation for arrival times of downward waves and the ray parameter conservation equation is investigated. Solutions to these equations coincide for pre-critical incidence angles and differ for super-critical angles. It is shown that the arrival times of maximum amplitude waves, which are of the greatest practical interest, coincide with the times calculated from the ray parameter field for the ray parameter conservation equation. The numerical algorithm proposed for calculation of these times can be used for arbitrary speed models. 相似文献
7.
MM. P. Duballet A. Godard G. Queguiner P. Pastour 《Journal of heterocyclic chemistry》1973,10(6):1079-1080
This article describes the synthesis of a new heterocycle, pyrido[2,3,f]phtalazine and three new diformylquinolincs. 相似文献
8.
M. S. Rovinskii V. G. Dolyuk V. B. Zhukhovitskii V. G. Shtamburg M. M. Kremlev 《Chemistry of Heterocyclic Compounds》1977,13(6):667-668
Arenesulfonamides are split out in the reaction of N-(arylsulfonyl)arylglyoxylamides with o-phenylenediamine to give 3-aryl-2-quinoxalones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 819–820, June, 1977. 相似文献
9.
The synthesis of two new heterocycles is described: pyrido-[2,3-d]-.s-triazolo[ 3,4-f] pyrimidine and pyrido[3,2-d]-.s-triayzolo-[3,4-f] pyrimidine. 4-[I'-Pyrazolyl]pyrido[2,3-d]pyrimidines and 4-[1′-pyrazoly1] pyrido[ 3,2-d] pyrimidine are obtained by the action of 4-hydrazinopyrido[2,3-d]pyrimidine and 4-hydrazinopyrido-[3,2-d]pyrimidine with several β-diketones. 相似文献
10.
We obtain a complete classification of all the possible values of the signature of the Ricci curvature of left-invariant Riemannian
metrics on four-dimensional nonunimodular Lie groups. 相似文献