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991.
V. V. Lipson M. G. Shirobokova O. V. Shishkin S. V. Shishkina 《Russian Journal of Organic Chemistry》2006,42(7):1015-1021
Cyclocondensation of 3-amino-5-methylpyrazole with 2-arylmethylidene-5,5-dimethylcyclohexane-1,3-diones or 9-aryl-3,3,6,6-tetramethyl-2,3,4,5,6,7,8,9-octahydro-1H-xanthene-1,8-diones, as well as with synthetic precursors of the latter (para-substituted benzaldehydes and dimedone), in dimethylformamide or methanol gives the corresponding 4-aryl-3,7,7-trimethyl-2,4,6,7,8,9-hexahydropyrazolo[3,4-b]quinolin-5-ones. The structure of 4-(4-methoxyphenyl)-3,7,7-trimethyl-2,4,6,7,8,9-hexahydropyrazolo[3,4-b]quinolin-5-one was proved by the X-ray diffraction data. 相似文献
992.
B. L. Tumanskii A. A. Kadyrov O. A. Popova L. T. Lantseva N. N. Bubnov S. P. Solodovnikov K. N. Makarov 《Russian Chemical Bulletin》1991,40(5):903-907
The EPR method was used to study the structure of spin adducts of silyl and phosphonyl radicals with higher internal perfluoroalkenes. The capacity for spin adducts to split off hydrogen atoms is determined by the degree of steric screening of the free radical center. The preparative photochemical reaction of hydrosilanes and dialkyl phosphites with perfluoro-4-methylpent-2-ene leads to regiospecific hydrosilylation and hydrophosphorylation products with yields up to 80%.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1018–1023, May, 1991. 相似文献
993.
N. Ya. Grigor'eva O. N. Yudina E. D. Daeva A. M. Moiseenkov 《Russian Chemical Bulletin》1990,39(1):76-84
A new procedure was developed for building linear Z-isoprenoids from glutaraldehyde derivatives as nonisoprenoid precursors, and is illustrated by the synthesis of hexaprenol WC5OH.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 89–97, January, 1990. 相似文献
994.
E. O. Chukhadzhyan K. G. Shakhatuni El. O. Chukhadzhyan N. T. Gevorkyan 《Chemistry of Heterocyclic Compounds》1999,35(3):343-347
Quaternary ammonium salts containing propargyl and 3-(2-methyltetrazol-5-yl)propargyl groups undergo base-catalyzed cyclization at room temperature with self heating to form condensed heterocyclic systems containing the tetrazole ring. Heating at 90–92°C for 2 h is necessary to cyclize the allyl analogs of the starting salts.Communication 234 of the series Research on Amines and Ammonium Compounds. For 233, see [1].Institute of Organic Chemistry, National Academy of Sciences of the Republic of Armenia, Erevan 375094. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 390–394, March, 1999. 相似文献
995.
996.
L. F. Kosyanchuk N. V. Kozak O. I. Antonenko G. Ya. Menzheres Yu. S. Lipatov 《Theoretical and Experimental Chemistry》2006,42(6):357-363
For semi-interpenetrating polymer networks (semi-IPNs) based on an incompatible polyurethane network/linear polymethylmethacrylate
pair formed in situ in the presence of 3d metal chelates, we have studied the effect of the system composition on the kinetics
of formation of the components and the nature of complex formation between the metal compound and the polymer matrix. The
ratio of the system components has been shown to have an effect on the selection of the macroligand in formation of complexes
of the metal chelate with the polar groups of the semi-IPN, where the general character of the kinetic behavior for the formation
of the network and the linear polymer is preserved.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 42, No. 6, pp. 351–356, November–December, 2006. 相似文献
997.
The potential of a package of quantum-chemical software programs for exploring physicochemical problems pertaining to polyatomic organic molecules is highlighted. The results of investigation into the spectral, luminescent, and photochemical properties of molecules are discussed. The necessity of development of target-oriented models for studying the problems of physics and chemistry of molecules is emphasized. 相似文献
998.
Gavrilov K. N. Bondarev O. G. Polosukhin A. I. Lyubimov S. E. Tzarev V. N. 《Russian Journal of Coordination Chemistry》2002,28(2):143-145
Optically active amidophosphite with the peripheral imino group (R)-(Et2N)2POCH2CH(Et)N=CHPh is synthesized through one-stage phosphorylation of the corresponding imino alcohol. Its reaction with [Rh(CO)2Cl]2 (at P : Rh = 1) yields the mononuclear chelate [Rh(CO)(P^N)Cl]. Structures of the compounds are determined by IR, 31P, and 13C NMR spectroscopy, mass spectrometry, and polarimetry. 相似文献
999.
O. F. Smetanina T. A. Kuznetsova A. V. Gerasimenko A. I. Kalinovsky M. V. Pivkin P. C. Dmitrenok G. B. Elyakov 《Russian Chemical Bulletin》2004,53(11):2643-2646
A new sesquiterpene of the caryophyllene series, fuscoatrol A (1), and known compounds, 11-epiterpestacin (2) and -nitropropionic acid (3), were isolated from the marine fungus Humicola fuscoatra (Traaen) KMM 4629 associated with the Kuril colonial ascidium. The structure of 1 was established on the basis of X-ray diffraction data and 2D NMR spectroscopy. The antimicrobial and cytotoxic activities of compounds 1–3 were studied.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2534–2537, November, 2004. 相似文献
1000.
A total synthesis of the above prenols has been carried out.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2333–2338, October, 1991. 相似文献