The present invention relates to a compound of formula (I) or (II) or a stereoisomer, enantiomer, racemic, or tautomer thereof, (I) (II) wherein R1, R2, R3, L1, L2, L3, L4, L5 and n, have the same meaning as that defined in the claims and the description. The present invention also relates to compositions, in particular pharmaceuticals, comprising such compounds, and to uses of such compounds and compositions for the prevention and/or treatment of metabolic disorders and/or neurodegenerative diseases, and/or protein misfolding disorders.