| Abstract: | The 3‐heteroaryl‐1‐methylpyridazino3,4‐b]quinoxalin‐4(1H)‐ones 6a‐e were synthesized by the oxidative‐hydrolytic ring transformation of the 3‐heteroaryl‐1,2‐diazepino3,4‐b]]quinoxaline‐5‐carbonitriles 9a‐c , which were obtained by the 1,3‐dipolar cycloaddition reaction of the 2‐(2‐heteroarylmethylene‐1‐methylhydrazino)quinoxaline 4‐oxides with 2‐chloroacrylonitrile. The assignment of the thiophene and furan ring protons was carried out through the data of the NOE, decoupling, and coupling constants. |
