1. Dipartimento Farmaco Chimico Tecnologico, Facoltà di Farmacia, University of Cagliari, 09124 Cagliari, Italy, Lipal Biochemicals, CH-8057 Zürich, Switzerland, and Department of Chemistry and Applied BioSciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology (ETH) Zurich, CH-8057 Zürich, Switzerland