1. Institute for Molecular Bioscience, Australian Research Council Special Research Centre for Functional and Applied Genomics, University of Queensland, Brisbane, Queensland, 4072, Australia, Molecular Targets Development Program, Center for Cancer Research, National Cancer Institute, Building 1052, Room 121, Frederick, Maryland 21702-1201, and Division of Pharmacognosy, Department of Medicinal Chemistry, Uppsala University, Biomedical Centre, Box 574, 751 23 Uppsala, Sweden