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Chemistry of Natural Compounds - 3-Epistrophanthidin and 3-epistrophanthidol have been synthesized from strophanthidin and strophanthidol with yields of 10 and 40%, respectively. The substances... 相似文献
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236.
Summary 1,2,3,4,7,7-Hexachlorobicyclo[2.2.1] hepta2, 5- diene, a starting material for the synthesis of the insecticides isodrin and endrin, was prepared by condensation of hexachlorocyclopentadiene with acetylene under pressure. 相似文献
237.
R. O. Kochkanyan M. M. Nechitailov P. Byszewski A. N. Zaritovskii A. F. Popov 《Russian Journal of Organic Chemistry》2004,40(7):957-961
Reaction of C60 fullerene with ferrocene in the presence of aluminum chloride and aluminum in an inert atmosphere gave ferrocenyl-substituted fullerene 2C60 ·1.5(C5H5)2Fe ·3H2O. The product is a thermally stable iron-containing carbon cage in which the intersphere cavity is formed by three C60 polyhedra and is closed by cyclopentadienyl ligands via formation of four carbon-carbon bonds. 相似文献
238.
N. S. Prostakov Keti Sudzhi N. M. Mikhailova L. A. Murugova V. F. Zakharov 《Chemistry of Heterocyclic Compounds》1981,17(10):1038-1042
1-Methyl-1H-indeno[1,2-b]pyridine and 1-methyl-1H-5-(, -dicarbomethoxyvinyl)-(formyl, acetyl)indeno[3,2-b]pyridines were obtained by treatment of N-methyl-4-azafluorenium iodide, as well as mixtures of it with acetylenedicarboxylic ester, dimethylformamide (DMF), and phosphorus oxychloride or acetic anhydride, with bases. 4-Azafluoronenone was used to synthesize 9-(p-methoxyphenyl)-4-azafluoren-9-ol, which was reduced to 9-(p-methoxyphenyl)-4-azafluorene, and 1-methyl-1H-5-(p-methoxyphenyl)indeno[3,2-b]pyridine was obtained from the methiodide of the latter.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1382–1386, October, 1981. 相似文献
239.
A method for the determination of low levels of ammonium ion in solution by optical emission spectrometry with an inductively coupled argon plasma source operated at 27 MHz is presented. The ammonium ion is oxidized with sodium hypobromite in alkaline medium, the evolved nitrogen is passed into the argon plasma, and the NH emission intensity produced in the plasma at 336.0 nm is monitored. A practical detection limit of 0.1 μg N ml-1 for 5-ml aqueous sample solutions has been obtained. The method has been applied to the determination of the exchangeable ammonium content of soil samples. 相似文献
240.
A. G. Nemazanyi Yu. M. Volovenko V. V. Neshchadimenko F. S. Babichev 《Chemistry of Heterocyclic Compounds》1992,28(2):220-222
The possibility of obtaining 3-amino-1,2-benzothiazine 1,1-dioxides by nucleophilic substitution of the chlorine atom in 5-nitro-2-chlorobenzenesulfonamides by carbanions generated from substituted acetonitriles was studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 264–266, February, 1992. 相似文献