1. The Institute of Organic and Physical Chemistry of Russian Academy of Sciences, Kazan, 420083, Tatarstan Republic, the Russian Federation, Departamento de Quimica Organica, Facultad de Quimica, Universidad de Santiago de Compostela, 15706, Santiago de Compostela, Spain, and Department of Chemistry, University of Connecticut, 55 N. Eagleville Road, 4-60, Storrs, Connecticut 06269-3060