1. W. Kong, J. Wei, P. Abidi, M. Lin, S. Inaba, C. Li, Y. Wang, Z. Wang, S. Sil, H. Pan, Sh. Wang, J. Wu, Y. Wang, Z. Li, J. Liu, and J.-D. Jiang, Nat. Med., 10, 1344 (2004); W. J. Kong, J. Liu, and J. D. Jiang, J. Mol. Med., 84, 29 (2006).
2. J. M. Beale and J. H. Block, eds., Wilson and Gisvold’s Textbook of Organic Medicinal and Pharmaceutical Chemistry, 12th Ed., Wolters Kluwer, Lippincott Williams & Wilkins, Philadelphia, 2011.
3. K. Iwasa and M. Kamigauchi, Phytochemistry, 41 (6), 1511 (1996).
4. Yu. D. Sadykov, S. B. Davidyants, K. T. Poroshin, I. N. Grigina, Dokl. Akad. Nauk Tadzh. SSR, 10 (2), 18 (1967).
5. G. Frerichs and P. Stoepel, Arch. Pharm., 251, 321 (1913).