Tetracyanoethene and 1‐Amino‐1,2,2‐ethenetricarbonitrile in the Synthesis of Heterocycles of Prospective Antioxidant and Antibacterial

Reaction of 1,1,2,2‐ethenetetracarbonitrile (TCNE) with aroyl thioureas in dioxane catalyzed by few drops of piperidine, led to the corresponding 1,2,4‐oxathiazoles. Under the same reaction condition, thiosemicarbazide or thiosemicarbazone reacted with either TCNE or 1‐amino‐1,2,2‐ethene‐tricarbonitrile. The structures of the products were elucidated via NMR, IR, mass spectra, and elemental analyses. The mechanism of formation was discussed. Biological (against Gram‐positive and Gram‐negative bacteria) and antioxidant activities were tested. Some of these heterocyclic compounds showed high activity as antioxidant and antibacterial compounds. The structure–activity relationship was investigated.