1. Michael, J. P. Nat. Prod. Rep. 1997, 21–41. Michael, J. P. Nat. Prod. Rep. 1997, 619–636. Michael, J. P. Nat. Prod. Rep. 1998, 571–594. Daly, J. W.; Garraffo, H. M.; Spande, T. F. In The Alkaloids; Academic Press: New York, 1993; 43, 185–288.
2. Aronstam, R. S.; Daly, J. W.; Spande, T. F.; Narayanan, T. K.; Albuquerque, E. X. Neurochem. Res. 1986, 11, 1227–1240.
3. Polniaszek, R. P.; Belmont, S. E. J. Org. Chem. 1990, 55, 4688–4693. Stevens, R. V. Accounts of Chemical Research 1984, 17, 289–296.
4. Bardou, A.; Celerier, J. P.; Lhommet, G. Tetrahedron Lett. 1998, 39, 5189–5192. Thanh, G. V.; Celerier, J. P.; Lhommet, G. Tetrahedron: Asymmetry 1996, 7, 2211–2212.
5. Takahata, H.; Kubota, M.; Ihara, K.; Okamoto, N.; Momose, T.; Azer, N.; Eldefrawi, A. T.; Eldefrawi, M. E. Tetrahedron: Asymmetry 1998, 9, 3289–3301.