The new product 3-oximino-4-oxo-2,5-dimethyl-tetrahydrofuran is manufactured by oximation of the new product 3-carboxy-4-oxo-2,5-dimethyl-tetrahydrofuran with aqueous nitrous acid, nitrite esters or nitrosyl chloride. Because of its fine caramel-like fragrance it may be used for the manufacture of scents and flavor materials. In addition it presents an advantageous method of synthesis of the sought-after flavor material 4-oxo-3-hydroxy-2,5-dimethyl-4,5-dihydrofuran (furaneol).