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71.
The mutual orientation of the heterorings and the three-dimensional structure of the kinetic product of the reaction of N-methylquinoxalinium iodide with thioacetamide were established by x-ray diffraction analysis of 2,4-dimethyl-9-acetyl-3a,4,9,9a-tetrahydrothiazolo [4,5-b]quinoxaline.See [1] for communication 18.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1417–1421, October, 1985.  相似文献   
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Reactions of 3-fluoro-1-nitrobenzenes with guanidine hydrochloride in THF in the presence of ButOK gave isomeric 5-and 7-fluoro-containing 3-amino-1,2,4-benzotriazines. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1196–1200, July, 2006.  相似文献   
74.
The cyclization of N-methylquinoxalinium iodide with ammonium salts of N-alkyl-dithiocarbamic acids in DMSO leads to 4-methyl-2,3,3a,4,9,9a-hexahydrothiazolo-[4,5-b]quinoxalines, whereas regioisomeric cycloadducts with a reversed orientation of the thiazole ring are formed in ethanol in the presence of diethylamine.See [1] for communication 9.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 680–685, May, 1984.  相似文献   
75.
The reactions of 3-aryl-1,2,4-triazines with aromatic thioamides and 4-arylthiosemicarbazides in acetic anhydride at room temperature afforded cyclic products of the tandem nucleophilic addition reactions, viz., tetrahydrothiazolo[4,5-e]-annelated 1,2,4-triazines, in good yields. The latter underwent aromatization in the presence of potassium permanganate.  相似文献   
76.
Novel 5,11-dialkyl-6,12-di(thiophen-2-yl) substituted 5,11-dihydroindolo[3,2-b]carbazoles have been obtained and plausible ways for their further modifications via the Friedel–Crafts reaction are presented. The formylation of these indolo[3,2-b]carbazoles with dichloromethyl alkyl esters catalysed by Lewis acids leads to the formation of the corresponding 2,8-diformyl derivatives. Applicability of this formylation method for modification of indolo[3,2-b]carbazoles bearing electron-rich aromatic substituents at C-6 and C-12 has also been demonstrated. The Knoevenagel condensation of 2,8-dialdehydes with active methylene nitriles has been studied. The measurements of optical and redox properties for a number of new indolo[3,2-b]carbazoles have been performed.  相似文献   
77.
The reaction of [60]fullerene with 2-azidopyrimidines affords fullerenoimidazopyrimidines, whose electron affinity is higher than that of nonmodified C60.  相似文献   
78.
Aromatic, heteroaromatic, and aliphatic carbonyl compounds reacted with 6-nitro[1,2,4]triazolo[1,5-a]pyrimidine in the presence of a base to give stable σH-adducts at C7. Reduction of the nitro group in the latter is accompanied by tandem autoaromatization of the azine ring and intramolecular cyclocondensation with formation of the corresponding 6H-pyrrolo[2,3-e][1,2,4]triazolo[1,5-a]pyrimidines. Original Russian Text ? E.B. Gorbunov, G.L. Rusinov, R.I. Ishmetova, V.N. Charushin, O.N. Chupakhin, 2008, published in Zhurnal Organicheskoi Khimii, 2008, Vol. 44, No. 1, pp. 130–134. Dedicated to Full Member of the Russian Academy of Sciences G.A. Tolstikov on his 75th anniversary  相似文献   
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