1, 2-Cyclopentanedione dioxime (II), 1, 2, 3-cyclohexanetrione trioxime (III) and 1, 3, 5- cyclohexanetrione trioxime (IV) were treated with reagents and exhibited different and characteristic behaviors in liquid sulfur dioxide. The formation of 5, 6-dihydro-4H-cyclopenta- [c] furazan (V) from II with thionyl chloride by a condensation reaction and of γ-cyanobu-tyric acid (VI) from II with sulfur trioxide by a cleavage reaction were observed. 7-Hydroxi-rnino- ...