1. Butler, R.N., Comprehensive Heterocyclic Chemistry, II, Katritzky, A.R., Rees, C.W., and Scriven, E.F.V., Eds., Oxford: Pergamon, 1996, vol. 4, p. 621.
2. Herr, R.J., Bioorg. Med. Chem., 2002, vol. 10, p. 3379.
3. Wittenberger, S.J., Org. Prep. Proced. Int., 1994, vol. 26, p. 499.
4. Ostrovskii, V.A., Pevzner, M.S., Kofman, T.P., Shcherbinin, M.B., Tselinskii, I.V., Targets in Heterocyclic Systems. Chemistry and Properties, Attanasi, O.A. and Spinelli, D., Eds., Rome: Societa Chimica Italiana, 1999, vol. 3, p. 467.
5. Ostrovskii, V.A. and Koldobskii, G.I., Ros. Khim. Zh., 1997, vol. 41, no. 2, p. 84.