The present invention relates to new compounds of formula I wherein R.sup.1, R.sup.2, R.sup.3, n, m are defined as in claim 1, a process for their preparation and new intermediates used in the preparation thereof, pharmaceutical formulations containing said therapeutically active compounds and to the use of said active compounds in therapy, especially in the prevention and/or treatment of dementia related diseases, Alzheimer's Disease and conditions associated with glycogen synthase kinase-3. 1