1. M. Jang, L. Cai, C. W. W. Beecher, H. H. S. Fong, N. R. Farnsworth, A. D. Kinghorn, J. M. Pezzuto, Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, USA.
2. G. O. Udeani, Department of Pharmacy Practice, University of Illinois, Chicago, IL 60612, USA.
3. K. V. Slowing, Departmento de Farmacologia, Universidad Complutense de Madrid, 28040 Madrid, Spain.
4. C. F. Thomas, R. G. Mehta, R. C. Moon, Department of Surgical Oncology, College of Medicine, University of Illinois, Chicago, IL 60612, USA.