Activated nitriles in heterocyclic synthesis. Part III. Synthesis of N‐amino‐2‐pyridone, pyranopyrazole and thiazolopyridine derivatives

The reaction of 2‐cyanoethanoic acid hydrazide and arylidenemalononitrile was studied as a new route for the synthesis of N ‐amino‐2‐pyridones. Pyrano[2,3‐c]pyrazole and thiazolo[2,3‐ a ]pyridine could be prepared from the reaction of arylideneazolones with the same reagent.