The present invention comprises cyclic N-[1,3,4]-thiadiazol-2-yl-benzene sulfonamides, their functional derivatives as well as their physiologically acceptable salts and pharmaceutical compositions thereof that exhibit peroxisome proliferator activated receptor (PPAR) PPARdelta and PPARgamma agonist activity. The structure of the compounds of the invention are defined by Formula I below, wherein the various R1-R9 substituents are defined herein. Processes for the compounds preparation are also disclosed. The compounds are suitable for the treatment of fatty acid metabolism and glucose utilization disorders, disorders relating to insulin resistance are involved as well as demyelinating and other neurodegenerative disorders of the central and peripheral nervous system.