The topics of this joint exchange programme are all related to a specific plant genus of commercial interest and its taxonomy, the propagation and investigation of endangered species of this plant genus, the natural products used in medicine occurring in Digitalis plants, and the isolation, structure elucidation and biological testing of some of the rare but pharmacological relevant cardenolides. Objectives are (1) Taxonomically critical Digitalis species and subspecies will be (re)-examined by molecular taxonomy, using the progesterone 5β-reductase gene as a molecular marker, and chemotaxonomy by cardenolide profiling, using HPLC, (2) plant tissue cultures of endangered Digitalis species will be established and used in plant propagation. Hairy root cultures of selected species will be established for fundamental studies on cardenolide formation, (3) the structures of important cardenolides will be elucidated by NMR and bulk quantities of selected cardenolides will be produced, (4) antiviral and antiproliferative effects of individual cardenolides will be studied. Cardenolides will be screened for their pharmacological profiles (potential and selectivity). The objectives aim at intensifying circumstantial ongoing co-operations and exchange of materials and people in a more reliable and coordinated way. The profiles of expertise of the various partners are complementary and researchers from Turkey, Brazil, Germany and Portugal are involved.