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1.
Golovchenko A. V. Pil'o S. G. Brovarets V. S. Drach B. S. 《Russian Journal of General Chemistry》2003,73(11):1832-1833
Russian Journal of General Chemistry - 相似文献
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O. B. Smolii L. V. Muzychka A. N. Chernega B. S. Drach 《Russian Journal of General Chemistry》2005,75(4):527-532
The substituted vinylphosphonium salt (E)-MeSCH=C(CN)P+Ph3I− readily cyclizes under the action of benzamidine and 3-amino-s-triazole, but it does not enter cyclocondensation with 2-aminopyridine. The structure of the cyclization product with 3-amino-s-triazole was confirmed by its transformation to 7-imino-6-(triphenylphosphoranylidene)-6,7-dihydro-s-triazolo[1,5]pyrimidine which was identified by X-ray diffraction. This stabilized ylide and its analogs proved useful starting materials for regioselective syntheses of 2-R-4-alkyl-4,7-dihydro-s-triazolo[1,5-a]pyrimidin-7-ones.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 4, 2005, pp. 565–570.Original Russian Text Copyright © 2005 by Smolii, Muzychka, Chernega, Drach. 相似文献
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LoSecco JM Bionta RM Biewitt G Bratton CB Casper D Chrysicopoulou P Claus R Cortez BG Errede S Foster GW Gajewski W Ganezer KS Goldhaber M Haines TJ Jones TW Kielczewska D Kropp WR Learned JG Lehmann E Park HS Reines F Schultz J Seidel S Shumard E Sinclair D Sobel HW Stone JL Sulak L Svoboda R van der Velde JC Wuest C 《Physical review letters》1985,54(21):2299-2301
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For embedded closed curves with curvature bounded below, we prove an isoperimetric inequality estimating the minimal area bounded by such curves for a fixed perimeter. 相似文献
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B. S. Drach V. S. Brovaretz O. R. Smolii 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Three types of high-polar phosphonlum compounde (1-111) containing imidazole cycle were obtained from the readily available acylaminomethylphosphonlum ralts (1). In spite of meeorneric character, these compounde react with electrophilic reagentr in a regfoeelective manner. Depending on the nature of endo- and exocyclic nucleophi-lic centere they can rhow properties either of typical ylidee or betainee. Many of them are valuable precuraore In aynthesis of new types of substituted imidazoles (IV, V) 相似文献
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Kristjan S. Gudmundsson Jack M. Hinkley Michael S. Brieger John C. Drach Leroy B. Townsend 《合成通讯》2013,43(5):861-870
An efficient large scale synthesis of 2-amino-4-chloropyridine (3) has been achieved through a modification of existing literature procedures. Compound 3 was used to prepare the previously unreported 2-amino-4,5-dichloropyridine (4). The known 2-amino-3,4-dichloropyridine (5) and 2-amino-3,4,5-trichloropyridine (6) were prepared from 3 by new routes and in higher yields than previously reported. 相似文献
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John?F?StinsEmail author G?Caroline?M?van Baal Tinca?JC?Polderman Frank?C?Verhulst Dorret?I?Boomsma 《BMC neuroscience》2004,5(1):49