Efficient synthesis of nebularine and vidarabine via dehydrazination of (hetero)aromatics catalyzed by CuSO4 in water

A simple dehydrazination reaction has been achieved in the presence of a catalytic amount of CuSO4 for the first time. With CuSO4 (2 mol%) as a catalyst and water as a solvent, the dehydrazination products were obtained in good yields (66–95%). Moreover, the drugs nebularine and vidarabine were afforded successfully, and vidarabine could be produced on a 0.923 kg scale, which shows good potential for industrial applications.