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81.
V. S. Arutyunyan T. V. Kochikyan Z. Yu. Nalbandyan M. A. Samvelyan A. A. Avetisyan 《Russian Journal of Organic Chemistry》2001,37(1):109-111
A new method was developed for synthesis of 2-acetonyl-4-alkoxymethylbutanolides by treatment of 4-alkoxymethyl-2-(-chloroallyl)butanolides with concentrated sulfuric acid and subsequent hydrolysis. 4-alkoxymethyl-2-(-chloroallyl)butanolides are readily obtained by alkylation of accessible 4-alkoxymethyl-2-ethoxycarbonylbutanolides with 2,3-dichloropropene, followed by hydrolysis and decarboxylation of the resulting 4-alkoxymethyl-2-(-chloroallyl)-2-ethoxycarbonylbutanolides. 相似文献
82.
A. A. Avetisyan A. G. Alvandzhyan T. A. Kostanyan M. M. Bidar 《Russian Journal of Organic Chemistry》2011,47(6):910-913
Reactions of functionally substituted unsaturated five- and six-membered cyanolactones with α- and β-hydroxy ketones in the
presence of sulfuric acid gave substituted 2-oxofuran- and 2-oxopyran-3-carboxamides. Hydrolysis of some keto amides thus
obtained afforded the corresponding carboxylic acids, and reactions with hydrazines and semicarbazides led to hydrazones and
semicarbazones at the side-chain oxo group. 相似文献
83.
The dynamics of a spherical cavity in a non-Newtonian fluid, described by the Reiner-Rivlin rheological equation [1], is investigated. The equation of radial cavity motion is obtained, where the gas in the cavity is subject to a polytropic law and surface tension is taken into account. The equation of cavity motion is solved numerically for a number of values of the transverse viscosity coefficient. The influence of the transverse viscosity on the collapse process of vapor and gas-filled cavities is shown. Numerical computations are also carried out for the rate of energy dissipation and the pressure distribution in the fluid.Translated from Izvestiya Akademiya Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 4, pp. 170–173, July–August, 1973.The authors are grateful to A. T. Listrove for attention to the research. 相似文献
84.
J.A. L’huillier G. Torosyan M. Theuer C. Rau Y. Avetisyan R. Beigang 《Applied physics. B, Lasers and optics》2007,86(2):197-208
Optical rectification of femtosecond pulses in nonlinear materials is an efficient method to generate ultra-short terahertz
(THz) pulses in a wide frequency range extending from 100 GHz to well above 10 THz. Lithium niobate (LN) is well suited for
such a purpose despite the high absorption in the THz range. In this part we will focus on the various experimental realizations
to produce THz radiation in bulk, periodically, aperiodically and two-dimensionally poled LN. The possible bandwidth, tunability
and the techniques to overcome the high absorption will be discussed as well.
PACS 42.65.Ky; 42.70.Mp; 42.72.Ai 相似文献
85.
T. V. Kochikyan M. A. Samvelyan V. S. Harutyunyan A. A. Avetisyan 《Chemistry of Heterocyclic Compounds》2005,41(11):1362-1370
A method was developed for the production of 4-alkoxy-2-ethoxycarbonyl-2-ethoxycarbonylmethylbutanolides. The latter were
subjected to alkaline and acid hydrolysis, leading to 4-alkoxymethyl-2-carboxymethylbutanolides, from which lactone-containing
thioureas and amides of carboxylactones with novel structures were obtained.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1625–1633, November, 2005. 相似文献
86.
E. G. Mesropyan G. B. Hambardzumyan A. A. Avetisyan A. S. Galstyan A. G. Khachatryan 《Chemistry of Heterocyclic Compounds》2005,41(8):962-966
The reaction of 5,5-dimethylhydantoin, benzotriazole, benzimidazole, morpholine, pyrrolidone, caprolactam, and phthalimide
with allyl glycidyl ether gave the corresponding heterylhydroxypropyl allyl ethers, the structures of which were confirmed
by spectral data and elemental analysis.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1135–1139, August, 2005. 相似文献
87.
88.
A. A. Avetisyan I. L. Aleksanyan K. S. Sargsyan 《Russian Journal of Organic Chemistry》2008,44(11):1645-1648
A convenient synthetic procedure for substituted 2-bromomethyl-4-methyl-2-chloro-2,3-dihydrofuro[3.2-c]quinolines hydrobromides was developed, synthons for preparation of new substituted furoquinolines. Reactions with various nucleophiles were performed, and 2-(R’-methyl)-4-methyl-furo[3.2-c]quinolines substituted in the benzene ring were obtained. 相似文献
89.
A. A. Avetisyan I. L. Aleksanyan L. P. Ambartsumyan 《Russian Journal of Organic Chemistry》2008,44(5):723-727
By a reaction of 2-methyl-4-chloroquinolines with o-mercaptoaniline under various conditions synteses were performed of substituted in the benzene ring 4-[(2-aminophenyl)thio]-2-methylquinolines and (4E)-4-[(2-mercaptophenyl)imino]-2-methyl-1,4-dihydroquinolines that were respectively by isomerization or rearrangement converted into 4-[(2-mercaptophenyl)amino]-2-methylquinolines. 相似文献
90.
T. V. Kochikyan E. V. Arutyunyan V. S. Arutyunyan A. A. Avetisyan 《Russian Journal of Organic Chemistry》2008,44(12):1799-1803
Alkylation of ethyl 2-oxotetrahydrofuran-3-carboxylates with 2,3-dichloroprop-1-ene and 3-bromoprop-1-yne gave new 3,5,5-tri- and 3,3,5,5-tetrasubstituted tetrahydrofuran-2-ones which were converted into the corresponding 3-(2-oxopropyl)tetrahydrofuran-2-ones. Reactions of the latter with semicarabazide, thiosemicarbazide, and phenylhydrazine were studied with a view to obtain new heterocyclic lactones. 相似文献