1. Department of Medicinal Chemistry, Royal Danish School of Pharmacy, Universitetsparken 2, DK-2100 Copenhagen, Denmark, Department of Chemistry, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark, Centre for Medical Parasitology, Department of Clinical Microbiology, Copenhagen University Hospital, Tagensvej 20, DK-2200 Copenhagen, Denmark, and Medicinal Plants Unit, Isfahan Research Centre of Natural Resources and Animal Science, Isfahan, P.O. Box 81785-114, Islamic Republic of Iran