1. Medicinal Chemistry Research, H. Lundbeck A/S, 9 Ottiliavej, DK-2500 Valby, Denmark, Department of Medicinal Chemistry, The Royal Danish School of Pharmacy, 2 Universitetsparken, DK-2100 Copenhagen, Denmark, and Biological Research, H. Lundbeck A/S, 9 Ottiliavej, DK-2500 Valby, Denmark