Design and synthesis of 2,6-disubstituted-8-amino imidazo[1,2a]pyridines,a promising privileged structure

Imidazo1,2a]pyridines have gained much interest in the field of medicinal chemistry research. In the aim of accessing new privileged structure, we decided to design and synthesize 8-aminated-imidazo1,2a]pyridines substituted on positions 2 and 6. This scaffold, rarely found in the literature, was obtained via palladium-catalyzed coupling reactions (Suzuki reaction or N-hydroxysuccinimidyl activated ester method) and tested on adenosine receptor A_2A. We demonstrated how incorporation of an exocyclic amine enhanced affinity towards this receptor while maintaining low cytotoxicity.