1. V. V. Zalesov, A. E. Rubtsov, and O. A. Bystritskaya, Zh. Org. Khim., 43, 739 (2007).
2. V. V. Zalesov and A. E. Rubtsov, Khim. Geterotsikl. Soedin., 163 (2004). [Chem. Heterocycl. Comp., 40, 133 (2004)].
3. R. W. Sabnis, D. W. Rangnekar, and N. D. Sonawane, J. Heterocycl. Chem., 36, 333 (1999).
4. A. E. Rubtsov and V. V. Zalesov, Zh. Org. Khim., 39, 918 (2003).