1. Y.-G. Zhou, P.-Y. Yang, and X.-W. Han, J. Org. Chem., 70(5), 1679 (2005).
2. I. V. Mashevskaya and A. N. Maslivets, 2,3-Dihydro-2,3-pyrrolediones Condensed with Various [a]-Side Heterocycles and Their Benzo[b] Analogs: Synthesis and Practical Applications [in Russian], Perm (2003), p. 106.