Fast and highly efficient one-pot synthesis of 9-deazaxanthines

SnCl2 enables a direct, high-yield conversion of 5-nitro-1,3-dialkyl-6-styryl(furyl-, thienyl-vinyl)-uracils to 8-substituted-9-deazaxanthines under very mild experimental conditions. The method has a general applicability and it is compatible with the reactivity of the most common organic functional groups. In slightly experimental different conditions, it allows a high-yield and fast (<5 min) preparation of pure 7-N-hydroxy-9-deazaxanthines.