Stereochemical features of addition of O- and C-nucleophiles to 5-(Het)aryl-2,3-dicyano-1-ethylpyrazinium salts [Electronic resource] / E. V. Verbitskiy, G. L. Rusinov, P. A. Slepukhin, A. N. Grishakov, M. A. Ezhikova, M. I. Kodess, V. N. Charushin // Russian Journal of Organic Chemistry (Translation of Zhurnal Organicheskoi Khimii). - 2008. - Vol. 44, № 2. - P. 302-310. - URL: http://www.springerlink.com/content/g1140h3048v07557/fulltext.pdf. - (Дата обращения: 28.10.2011 г.)