1. Department of Medicinal Chemistry, Institute for Pharmacy and Food Chemistry at the Emil-Fischer Center, Friedrich Alexander University Erlangen, Schuhstrasse 19, D-91052 Erlangen, and Institute of Pharmaceutical Chemistry, ZAFES, University of Frankfurt, D-60439 Frankfurt, Max-von-Laue-Strasse 9, Germany, and Department of Pharmaceutical Analytics, Institute of Pharmacy, Eberhard-Karls-University Tubingen, Auf der Morgenstelle 8, 72076 Tubingen, Germany