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1.
A. A. Avetisyan I. L. Aleksanyan A. G. Alvandzhyan 《Chemistry of Heterocyclic Compounds》1996,32(7):773-776
A synthesis has been developed for substituted coumarins and 2-thioxo-2H-chromenes and some of the chemical transformations of these compounds were studied.Yerevan State University, 375049 Yerevan, Armenia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 909–912, July, 1996. Original article submitted December 30, 1995; revision submitted April 16, 1996. 相似文献
2.
M. B. Ordyan V. S. Grigoryan R. V. Avetisyan Ya. T. Éidus 《Russian Chemical Bulletin》1971,20(5):1034-1036
Conclusions When the hydrocarbomethoxylation of 1-hexene with formic acid is run at atmospheric pressure and temperatures close to room temperature, in the presence of conc. H3PO4, an increase in the relative amount of the latter, as well as an increase in the reaction temperature in the investigated range, both favor an increase in the yields of the methyl esters of the C7 acids, in particular, those containing two methyl groups on the quaternary carbon atom in the -position. An increase in the relative amount of formic acid also favors an increase in the amounts of these esters in the obtained mixtures of esters.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1116–1118, May, 1971. 相似文献
3.
V. F. Cherstkov É. A. Avetisyan B. L. Tumanskii S. R. Sterlin N. N. Bubnov L. S. German 《Russian Chemical Bulletin》1990,39(10):2223-2223
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2450–2451, October, 1990. 相似文献
4.
A. A. Avetisyan I. L. Aleksanyan A. A. Pivazyan 《Russian Journal of Organic Chemistry》2006,42(5):739-741
4-Hydroxy-2-methyl-3-(2-chloro-2-propenyl)quinoline was prepared by O-allylation of 4-hydroxy-2-methylquinoline followed by the Claisen rearrangement of the 2-methyl-4-(2-chloro-2-propenyloxy)quinoline obtained. Chemical modifications of 4-hydroxy-2-methyl-3-(2-chloro-2-propenyl)quinoline resulted in the synthesis of 4-amino-2-methyl-3-(2-methyl-3-indolyl)quinoline. 相似文献
5.
6.
A. S. Saghiyan A. V. Geolchanyan L. L. Manasyan G. M. Mkrtchyan N. R. Martirosyan S. A. Dadayan T. V. Kochickyan V. S. Harutyunyan A. A. Avetisyan V. I. Tararov V. I. Maleev Yu. N. Belokon' 《Russian Chemical Bulletin》2004,53(4):932-935
An efficient method was developed for the asymmetric synthesis of (R)-S-(1,2,4-triazol-3-yl)cysteines by the addition of 3,4-disubstituted 1,2,4-triazole-5-thiols at the electrophilic C=C bond in a NiII complex of a Schiff base of dehydroalanine with (S)-N-(N-benzylprolyl)aminobenzophenone. The stereoselectivity of the formation of diastereomeric complexes with the (S,R) configuration under conditions of thermodynamic control of the nucleophilic addition exceeds 94%. Acid treatment of the reaction mixtures afforded enantiomerically pure (R)-S-hetarylcysteines (ee >98%). 相似文献
7.
A. A. Avetisyan I. L. Aleksanyan L. P. Ambartsumyan 《Russian Journal of Organic Chemistry》2005,41(5):769-771
Synthesis was performed of substituted 2-methyl-4-quinoline thiouronium salts by reaction of 2-methyl-4-chloroquinolines with thiourea. The alkaline hydrolysis of these salts afforded the corresponding 2-methyl-4-quinolyl- isothiocyanates and 2-methyl-4-mercaptoquinolines.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 5, 2005, pp. 783–785.Original Russian Text Copyright © 2005 by Avetisyan, Aleksanyan, Ambartsumyan. 相似文献
8.
T. V. Kochikyan E. V. Harutyunyan V. S. Harutyunyan A. A. Avetisyan 《Chemistry of Heterocyclic Compounds》2006,42(1):109-114
By reaction of 8-substituted 3-bromoacetyl-3,8-dimethyl-2,7-dioxaspiro[4,4]nonane-1,6-diones with thiourea and substituted
thioureas under Hansch reaction conditions, we have obtained the novel heterocycles 3-[2′-amino(arylamino)thiazol-4-yl]-3,8-dimethyl-2,7-dioxaspiro[4,4]nonane-1,6-diones.
By reacting the above-indicated bromoacetyl spirodilactones with 5-aryl-3-mercapto-1,2,4-triazoles, we obtained 8-substituted
3-(aryl-3,8-dimethyl-1′,2′,4′-triazol-3′-yl)thioacetyl-2,7-dioxaspiro[4,4]nonane-1,6-diones.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 123–129, January, 2006. 相似文献
9.
A. A. Avetisyan I. L. Aleksanyan A. G. Alvandzhyan 《Chemistry of Heterocyclic Compounds》1997,33(1):39-42
A method has been developed for the synthesis of 3-(3,3-dichloroallyl)-4-hydroxycoumarin and 2-thioxo-3-(3,3-dichloroallyl)-4-hydroxy-2H-chromene, and certain conversions of these compounds have been studied. They undergo acid hydrolysis readily, forming (respectively) 3-(4-hydroxy-3-coumarin)- and 3-(2-thioxo-4-hydroxy-2H-chromene-3)propionic acids; these compounds are converted to the corresponding lactones by the action of acetic anhydride.Erevan State University, Erevan 375049. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 48–51, January, 1997. 相似文献
10.
Aida Avetisyan 《合成通讯》2013,43(17):2607-2609
A convenient procedure for the preparation of cerpegin is described. 相似文献