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1.
A reaction was studied of previously unknown 1,3-bis(2-hydroxy-3-chloropropyl)uracil, 1,3-bis(2- hydroxy-3-chloropropyl)-6-methyluracil, and 1,3-bis(2-hydroxy-3-chloropropyl)-5-fluorouracil with 1,3-bis[3-(3-methyl-2H-5-pyrazolon-1-yl)-2-hydroxypropyl]-6-methyluracil.  相似文献   
2.
Reactions of 1,3-bis(3-chloro-2-hydroxypropyl)uracil, 1,3-bis(3-chloro-2-hydroxypropyl)-6-methyluracil, 1,3-bis(3-chloro-2-hydroxypropyl)-5-hydroxy-6-methyluracil, and 1,3-bis(3-chloro-2-hydroxypropyl)-5-fluorouracil with 2-amino-4-methylthiobutanoic acid (methionine) were studied for the first time.  相似文献   
3.
The structure of the displacements in a Rayleigh-type wave that propagates in an isotropic solid covered with a liquid layer with exponentially varying density and sound velocity is investigated.  相似文献   
4.
2,4-Dioxo-1,2,3,4-tetrahydropyrimidin-5yl methacrylates were synthesized for the first time by reaction of 5-hydroxyuracil derivatives with methacrylic anhydride. 5-Hydroxyuracil derivatives are involved in this reaction in the dioxo form.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 1, 2005, pp. 141–143.Original Russian Text Copyright © 2005 by Krivonogov, Chernyshenko, Kozlova, Yakovleva, Spirikhin, Abdrakhmanov, Plechev, Sivkova, Battalov.  相似文献   
5.
Microporous organic polymers (MOP) of a new type have been synthesised in high yields by a simple coordination polymerization of 1,3‐diethynylbenzene, 1,4‐diethynylbenzene and 4,4′‐diethynylbiphenyl catalysed by [Rh(cod)acac] and [Rh(nbd)acac] complexes. The new MOPs are non‐swellable polyacetylene‐type conjugated networks consisting of ethynylaryl‐substituted polyene main chains that are crosslinked by arylene linkers. Prepared MOP samples have a mole fraction of branching units (by 13C CP/MAS NMR) from 0.30 to 0.47 and exhibit the BET (Brunaer‐Emmett‐Teller) surface up to 809 m2 g−1 and hydrogen uptake up to 0.69 wt% (77 K, H2 pressure 750 torr).  相似文献   
6.
A procedure was developed for synthesizing nitrogen-and-sulfur-containing pyrimidine derivatives by reactions of 1,3-bis(3-chloro-2-hydroxypropyl)-6-methyluracil with 1-butanethiol and chloroacetyl chloride, followed by treatment of the resulting 1,3-bis[3-chloro-2-(chloroacetoxy)propyl]-6-methyl-1,2,3,4-tetrahydropyrimidine-2,4-dione with 1-butanethiol, morpholine, and piperidine. Oxidation of the sulfur-containing products with NaIO4 gave the corresponding sulfoxides.  相似文献   
7.
The reaction of substituted methyl 1-adamantyl ketones with an equimolar amount of 5-phenyl-2,3-dihydrofuran-2,3-dione under the conditions of the thermal decarbonylation of the latter leads to the corresponding 2-methyl-2-adamantyl-6-pheny1-1,3-dioxen-4-ones, 6-phenyl-3-benzoyl-2,4-dione, and the starting ketones. The steric and electronic factors that affect the yields of the dioxen-4-ones were examined. -Hydroxymethyl 1-adamantyl ketones open up the furan ring to give 1-adamantoylmethyl benzoylpyruvate. Data from the IR, PMR, and UV spectra are presented.See [1] for communication 27.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1312–1315, October, 1982.  相似文献   
8.
The features of the kinetics of the initiation of detonation condensation waves in carbon suboxide and acetylene have been experimentally studied at high pressures near the low-temperature limits. The role of quantum effects in the expansion of detonation limits has been analyzed. Quantum corrections to the endothermic reaction rates, which are caused by an increase in the high-energy tails of the momentum distribution functions at high pressures due to the manifestation of the uncertainty principle for the energy of colliding particles at a high collision frequency, have been quantitatively estimated. It has been shown that experimentally observed deviations in Arrhenius dependences of the induction periods of the initiation of detonation condensation waves are well described by the proposed quantum corrections.  相似文献   
9.
A procedure was developed for synthesis of polycyclic pyrimidine derivatives by the reaction of 2,2'-dichlorodicyclohexyl sulfide with uracil, 6-methyluracil, or 5-fluorouracil in the presence of K2CO3, followed by oxidation of the resulting products with sodium metaperiodate and hydrogen peroxide. Two of the synthesized compounds were tested in extraction of Ir(IV) from hydrochloric acid solutions.  相似文献   
10.
A reaction was studied of newly synthesized 1,3-bis(2-hydroxy-3-chloropropyl)uracil and 1,3-bis(2-hydroxy-3-chloropropyl)-6-methyluracil with hydrazine hydrate followed by treating the compounds formed with ethyl acetoacetate. The hydrazones obtained cyclized into pyrazolones in the presence of sodium methylate.  相似文献   
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