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41.
Physics of the Solid State - The effect of surface processing by laser IR radiation on strength and Portevin–Le Chatelier serrated deformation of AlMg6 aluminum–magnesium alloy is...  相似文献   
42.
Hexachlorobicyclo[2.2.1]hepta-2,5-dienylmethyl haloacetates were prepared by [4+2]-cycloaddition of hexachlorocyclopentadiene to the corresponding propargyl haloacetates.  相似文献   
43.
Physics of the Solid State - Abstract—Using high-speed video recording, the stages of predestruction and development of a main crack initiated by pulsed infrared laser radiation on the...  相似文献   
44.
The rate constants for the addition of radicals CCl3CH2 ·CHR to unsaturated compounds CH2=CHR (R = Ph, CO2Me, CONC4H8) and to CH2=CMeCO2Me were determined at 22 °C by ESR spectroscopy.  相似文献   
45.
Mono- and diesters of N-benzoylaminoacetic acid, which exhibit high wear-preventive properties in a synthetic ester oil, were synthesized.  相似文献   
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A method has been developed for synthesis of 4-alkylthio-2-(o-hydroxyphenyl)-1,3,5-triazines by treatment of 4-oxo-1,3-benzoxazine perchlorates with S-methyl, benzyl, and allyl-isothioureas.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1658–1661, December, 1989.  相似文献   
49.
The rate constants of the addition of CCl3CH2ClCH3(R6) radicals to -methyl-styrene, styrene, methyl methacrylate, methyl acrylate, and acrylonitrile and of CCl3CH2(CH3)2(R7) radicals to styrene, methyl acrylate, and acrylonitrile were determined by ESR spectroscopy. It was shown that the radicals R6 and R7 possess approximately equal reactivity in addition to unsaturated compounds, despite the difference in the donor-acceptor properties of the substituents at the vinyl group. In a comparison of the reactivity of radicals R6 and R7 with the reactivity of radicals CCl3CH2H2(R1), CCl3CH2HCH3(R3), CCl3CH2HCl(R4), and ClCH2CH2Cl2(R5) [1] in addition reactions, it was shown that polar and steric effects of the substituents situated in the -position to the radical site of the above-mentioned radicals, as well as the donor-acceptor properties of the substituents at the vinyl group in the unsaturated compounds, lead to appreciable changes in reactivity.A. N. Nesmeyanov Institute of Heteroorganic Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 136–141, January, 1992.  相似文献   
50.
The scope and limitations of the Nicholas-type cyclization for the synthesis of 10-membered benzothiophene-fused heterocyclic enediynes with different functionalities were investigated. Although the Nicholas cyclization through oxygen could be carried out in the presence of an ester group, the final oxaenediyne was unstable under storage. Among the N-type Nicholas reactions, cyclization via an arenesulfonamide functional group followed by mild Co-deprotection was found to be the most promising, yielding 10-membered azaendiynes in high overall yields. By contrast, the Nicholas cyclization through the acylated nitrogen atom did not give the desired 10-membered cycle. It resulted in the formation of a pyrroline ring, whereas cyclization via an alkylated amino group resulted in a poor yield of the target 10-membered enediyne. The acylated 4-aminobenzenesulfonamide nucleophilic group was found to be the most convenient for the synthesis of functionalized 10-membered enediynes bearing a clickable function, such as a terminal triple bond. All the synthesized cyclic enediynes exhibited moderate activity against lung carcinoma NCI-H460 cells and had a minimal effect on lung epithelial-like WI-26 VA4 cells and are therefore promising compounds in the search for novel antitumor agents that can be converted into conjugates with tumor-targeting ligands.  相似文献   
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