The invention relates to compounds of formula (I) wherein R<1>, R<2>, R<3>, R<4>, R<5> and p are as defined in the description and claims as well as to pharmaceutically acceptable salts thereof per se and as pharmaceutically active substances. The invention also relates to their manufacture, medicaments based on a compound in accordance with the invention and their production, as well as the use of the compounds in accordance with the invention in the control or prevention of illnesses of the aforementioned kind, and, respectively, for the production of corresponding medicaments.